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    Amide Local Anesthetics

    DEA CLASS

    Rx

    DESCRIPTION

    Injectable amide-type local anesthetic
    Used for single-dose infiltration to produce postsurgical local analgesia and as interscalene brachial plexus nerve block to produce postsurgical regional analgesia
    Not bioequivalent to other formulations of bupivacaine

    COMMON BRAND NAMES

    EXPAREL

    HOW SUPPLIED

    EXPAREL Infiltration Inj Lipos: 1mL, 13.3mg

    DOSAGE & INDICATIONS

    For postsurgical local analgesia.
    Infiltration dosage

    NOTE: Bupivacaine liposomal is not bioequivalent with other formulations of bupivacaine and dosage conversion between bupivacaine liposomal and other formulations is not possible.
    NOTE: Bupivacaine liposomal is intended for single-dose administration only.

    Adults

    The dose is based on the surgical site, volume required to cover the area, and individual patient factors that may impact the safety of an amide local anesthetic; do not exceed 266 mg (20 mL). As general guidance for determining the dose, consider the following examples. In patients undergoing bunionectomy, 106 mg (8 mL) was administered by infiltrating 7 mL into the tissues surrounding the osteotomy and 1 mL into the subcutaneous tissue. In patients undergoing hemorrhoidectomy, 266 mg (20 mL) was diluted with 10 mL of 0.9% Sodium Chloride Injection to a total of 30 mL. The mixture was divided into six 5-mL aliquots, and each aliquot was slowly infiltrated around the anal sphincter.

    Children and Adolescents 6 to 17 years

    4 mg/kg (Max: 266 mg) via infiltration. This dose is based upon 2 studies of pediatric patients undergoing either spine or cardiac surgery.

    For interscalene brachial plexus nerve block to produce postsurgical regional analgesia.
    NOTE: Bupivacaine liposomal is not bioequivalent with other formulations of bupivacaine and dosage conversion between bupivacaine liposomal and other formulations is not possible.
    NOTE: Bupivacaine liposomal is intended for single-dose administration only.
    Regional dosage
    Adults

    133 mg (10 mL) interscalene once for patients undergoing either total shoulder arthroplasty or rotator cuff repair.

    MAXIMUM DOSAGE

    Adults

    266 mg for local infiltration; 133 mg for interscalene brachial plexus nerve block.

    Geriatric

    266 mg for local infiltration; 133 mg for interscalene brachial plexus nerve block.

    Adolescents

    4 mg/kg (Max: 266 mg) for local infiltration.

    Children

    6 to 12 years: 4 mg/kg (Max: 266 mg) for local infiltration.
    1 to 5 years: Safety and efficacy have not been established.

    Infants

    Safety and efficacy have not been established.

    Neonates

    Safety and efficacy have not been established.

    DOSING CONSIDERATIONS

    Hepatic Impairment

    Although specific guidelines for dosage adjustments in hepatic impairment are not available, bupivacaine is hepatically metabolized; caution in dosing is recommended.

    Renal Impairment

    Although specific guidelines for dosage adjustments in renal impairment are not available, bupivacaine is substantially excreted by the kidneys; caution in dosing is recommended.

    ADMINISTRATION

     
    Do not substitute bupivacaine HCl for liposomal bupivacaine. The encapsulation of a drug into a lipid complex can substantially affect its functional properties relative to those of the nonlipid-associated drug. Furthermore, different liposomal products with a common active ingredient may vary in chemical composition and physical form of the lipid component allowing for differences that may affect the functional properties of the drug.

    Injectable Administration

    Do not administer if the vial has been frozen or exposed to temperatures higher than 40 degrees C (104 degrees F) for an extended amount of time. Do not use the vial if the stopper is bulging.
    Visually inspect parenteral products for particulate matter and discoloration prior to administration whenever solution and container permit. Do not use if product is discolored.
    Resuscitative equipment and drugs used in the management of adverse reactions should be immediately available while administering liposomal bupivacaine.
    Liposomal bupivacaine is intended for single-dose infiltration only.
    Admixing liposomal bupivacaine with other drugs prior to administration is not recommended. Direct contact of liposomal bupivacaine with some drugs results in a rapid increase in free (unencapsulated) bupivacaine, which may adversely affect safety and/or efficacy.
    Bupivacaine HCl and liposomal bupivacaine may be administered simultaneously in the same syringe, and bupivacaine HCl may be injected immediately before liposomal bupivacaine if the ratio of the milligram dose of bupivacaine HCl to liposomal bupivacaine does not exceed 1:2.
    Liposomal bupivacaine may be administered after a delay of 20 minutes or more after the administration of lidocaine.
    When a topical antiseptic (e.g., Betadine) is applied, allow the site to dry completely before administering liposomal bupivacaine.
    Invert vials several times to re-suspend particles immediately prior to withdrawing the drug from the vial.
    Administer liposomal bupivacaine using a 25-gauge or larger bore needle. Do not filter or heat before use.
    Liposomal bupivacaine may be administered undiluted or diluted with 0.9% Sodium Chloride Injection or Lactated Ringer's Injection up to a concentration of 0.89 mg/mL (i.e., 1:14 dilution by volume). DO NOT dilute with water or other hypotonic agents; disruption of the liposomal particles will occur.
    Inject liposomal bupivacaine slowly (generally 1 to 2 mL per injection) with frequent aspiration to check for blood and minimize the risk of inadvertent intravascular injection.
    Avoid additional use of local anesthetics within 96 hours after administration of liposomal bupivacaine.
    Storage: Once a vial has been removed from refrigeration, do not refrigerate. Unopened vials may be stored at controlled room temperature (20 to 25 degrees C or 68 to 77 degrees F) for up to 1 month. Record the date when a vial is removed from refrigeration on the space provided on the label. After withdrawal from the vial, the suspension may be stored at controlled room temperature for up to 4 hours. Do not re-refrigerate.

    Other Injectable Administration

    Surgical Site Infiltration Administration
    Bunionectomy:
    Infiltrate 7 mL undiluted liposomal bupivacaine into the tissues surrounding the osteotomy and 1 mL into the subcutaneous tissue.
     
    Hemorrhoidectomy:
    Dilute 20 mL of liposomal bupivacaine with 10 mL of 0.9% Sodium Chloride Injection to make a total of 30 mL. Divide the mixture into six 5-mL aliquots. Perform anal block by visualizing the anal sphincter as a clock face and slowly infiltrating 1 aliquot into each of the even numbers.

    STORAGE

    EXPAREL:
    - Avoid excessive heat (above 104 degrees F)
    - Discard if product has been frozen
    - Discard unused portion. Do not store for later use.
    - Do not autoclave
    - Do not freeze
    - May be stored at controlled room temperature for up to 30 days in sealed, unopened vial
    - Refrigerate (between 36 and 46 degrees F)

    CONTRAINDICATIONS / PRECAUTIONS

    Epidural administration, intrathecal administration, intravenous administration

    Bupivacaine liposomal has not been studied for regional nerve blocks other than interscalene brachial plexus nerve block. Avoid intravenous administration, intra-articular administration, epidural administration, and intrathecal administration of bupivacaine liposomal. Unintended intravenous administration may result in convulsions and cardiac arrest. To avoid intravascular administration of bupivacaine liposomal, frequent aspiration should be performed during administration to check for blood.

    Continuous intraarticular infusion administration

    Liposomal bupivacaine is not approved for continuous intraarticular infusion administration. Infusion of local anesthetics into a joint space may have caused chondrolysis. Local anesthetics are not indicated for intraarticular postoperative infusions or for use with infusion devices such as elastomeric pumps.

    Hepatic disease

    Due to extensive liver metabolism of bupivacaine, use liposomal bupivacaine cautiously in patients with hepatic disease. Patients with hepatic disease are at greater risk of developing high plasma concentrations and subsequent toxicities due to decreased clearance of bupivacaine.

    Cardiac disease

    Local anesthetics, such as liposomal bupivacaine, should be used with caution in patients with impaired cardiac function or cardiac disease. Blood concentrations of bupivacaine achieved with normal therapeutic doses have minimal effects on cardiac function. However, toxic bupivacaine blood concentrations depress cardiac conductivity and excitability, which could cause AV block, ventricular arrhythmias, and sometimes fatal cardiac arrest. Decreased cardiac output and arterial blood pressure also may occur due to depressed myocardial contractility and peripheral vasodilation. Clinical reports and animal data suggest these cardiovascular changes are more likely to occur after inadvertent intravascular administration of bupivacaine. Elevated blood concentrations of bupivacaine may also occur after the injection of multiple doses due to slow accumulation or slow metabolism. Tolerance to elevated blood concentrations varies with the clinical status of the patient. Patients with impaired cardiac function, particularly AV block, may be less able to compensate for functional changes associated with prolonged AV conduction (i.e., PR or QT prolongation) caused by local anesthetics.

    Amide local anesthetic hypersensitivity

    Liposomal bupivacaine should not be used in patients with known amide local anesthetic hypersensitivity. Although rare, allergic-type reactions may occur due to the local anesthetic or other formulation ingredients. Cross sensitivity among the amide local anesthetic group has been reported, but the usefulness of screening for sensitivity has not been established.

    Renal disease, renal failure, renal impairment

    Use liposomal bupivacaine cautiously in patients with renal impairment or renal failure; liposomal bupivacaine is substantially excreted by the kidney. Patients with renal disease are at greater risk of developing high plasma concentrations and subsequent toxicities due to decreased clearance of bupivacaine. Use caution when choosing the dose of liposomal bupivacaine in patients with renal impairment.

    Labor, obstetric delivery, paracervical nerve block, pregnancy

    There are no studies with liposomal bupivacaine in human pregnancy. Obstetrical paracervical nerve block with liposomal bupivacaine is contraindicated. The use of bupivacaine HCl by this technique has resulted in fetal bradycardia and death. During labor and obstetric delivery, local anesthetics, like bupivacaine, can cause varying degrees of maternal, fetal, and neonatal toxicities. The potential for toxicity is related to the procedure performed, the type and amount of drug used, and the technique of administration. In animal reproductive studies, rabbits received liposomal bupivacaine subcutaneously during organogenesis at doses equivalent to 0.1, 0.4, and 1.6 times the maximum recommended human dose (MRHD) based on BSA comparisons and a 60-kg human weight; an increase in embryo-fetal deaths was observed at the high dose. During a rat pre- and post-natal development study, liposomal bupivacaine was given subcutaneously during pregnancy and lactation at doses equivalent to 0.2, 0.5, and 1.5 times the MRHD based on BSA comparisons and a 60-kg human weight, and decreased pup survival was observed at 1.5 times the MRHD.

    Breast-feeding

    Limited data indicate that bupivacaine and its metabolite, pipecoloxylidide, are present in human milk at low concentrations. There are no data on the effects of bupivacaine on the breast-fed infant or on milk production. Consider the developmental and health benefits of breast-feeding along with the mother's clinical need for liposomal bupivacaine and any potential adverse effects on the breast-fed infant from liposomal bupivacaine or from the underlying maternal condition.[46598] In general, use of local anesthetics during surgery or other procedures allows breast-feeding of the healthy term infant to be permissible as soon as the mother is awake and alert.[46104] In a study of 27 pregnant women undergoing cesarean delivery, administration of epidural anesthesia with 0.5% bupivacaine and 2% lidocaine during delivery had no effect on the breast-fed infant.[49514] A prospective cohort study comparing women who received no analgesia (n = 63) to women who received continuous epidural fentanyl and either bupivacaine 0.05% to 0.1% (n = 39) or ropivacaine (n = 13) during labor and delivery found no differences between the groups in breast-feeding effectiveness or infant neurobehavioral status at 8 to 12 hours postpartum.[49516] In 30 patients who underwent elective cesarean delivery, epidural bupivacaine use as part of a postoperative pain management regimen (n = 15) did not result in any significant difference to the time when breast-feeding started compared to spinal anesthesia alone (2.4 vs. 2.5 days).[60471]

    Requires an experienced clinician

    The use of liposomal bupivacaine requires an experienced clinician and should only be administered in a setting where trained personnel and equipment are available to effectively manage drug-related toxicity and other acute emergencies that might arise from the administration of a regional anesthetic block. Vital signs and cardiovascular and neurological status should be monitored during and after administration. The safety and efficacy of liposomal bupivacaine depend on proper dosage, technique, adequate precautions, and emergency preparedness. The immediate availability of oxygen, cardiopulmonary resuscitative equipment and drugs, and the appropriate support personnel for the management of toxic reactions or emergencies must be ensured. Any delay in appropriate management may lead to the development of neurologic toxicity, cardiac arrest, and possibly death.

    G6PD deficiency, infants, methemoglobinemia, neonates, pulmonary disease

    Methemoglobinemia has been reported with local anesthetic use. Although all patients are at risk for methemoglobinemia, patients with glucose-6-phosphate dehydrogenase deficiency (G6PD deficiency), preexisting (congenital or idiopathic) methemoglobinemia, cardiac or pulmonary compromise (cardiac disease or pulmonary disease), neonates and infants younger than 6 months, and those with concurrent exposure to oxidizing agents or their metabolites are more susceptible to developing methemoglobinemia. Monitor such patients closely for signs and symptoms of methemoglobinemia if a local anesthetic must be used. Signs of methemoglobinemia may occur immediately or may be delayed hours after exposure. Immediately discontinue the local anesthetic to avoid serious central nervous system and cardiovascular adverse events, as methemoglobin concentrations may continue to rise. Patients may require supportive care such as oxygen therapy and hydration. More severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.[46598]

    ADVERSE REACTIONS

    Severe

    bradycardia / Rapid / 1.3-8.8
    visual impairment / Early / 0-2.5
    respiratory arrest / Rapid / 0-2.0
    thrombosis / Delayed / 0-2.0
    ventricular tachycardia / Early / 0-2.0
    AV block / Early / 0-2.0
    cardiac arrest / Early / 0-2.0
    apnea / Delayed / 0-2.0
    laryngospasm / Rapid / 0-2.0
    atrial fibrillation / Early / 0.6-1.3
    anaphylactoid reactions / Rapid / 0-1.0
    laryngeal edema / Rapid / 0-1.0
    angioedema / Rapid / 0-1.0
    seizures / Delayed / Incidence not known
    coma / Early / Incidence not known
    muscle paralysis / Delayed / Incidence not known
    ventricular fibrillation / Early / Incidence not known
    chondrolysis / Delayed / Incidence not known
    methemoglobinemia / Early / Incidence not known

    Moderate

    constipation / Delayed / 2.1-25.0
    hypotension / Rapid / 2.0-22.5
    anemia / Delayed / 1.2-18.8
    blurred vision / Early / 0-13.8
    sinus tachycardia / Rapid / 1.3-11.3
    urinary incontinence / Early / 0-10.0
    peripheral edema / Delayed / 2.0-9.9
    tachypnea / Early / 8.8-8.8
    urinary retention / Early / 0-7.6
    confusion / Early / 0-5.0
    hypertension / Early / 0-5.0
    elevated hepatic enzymes / Delayed / 0-4.2
    hypokalemia / Delayed / 3.0-4.2
    hematuria / Delayed / 2.5-2.5
    hypoxia / Early / 0-2.4
    hematoma / Early / 0-2.4
    depression / Delayed / 0-2.0
    delirium / Early / 0-2.0
    bundle-branch block / Early / 0-2.0
    palpitations / Early / 0-2.0
    orthostatic hypotension / Delayed / 0-2.0
    dysuria / Early / 0-2.0
    respiratory depression / Rapid / 0-2.0
    erythema / Early / 0-2.0
    hyperthermia / Delayed / 0-2.0
    chest pain (unspecified) / Early / 1.3-1.3
    dyspnea / Early / 1.2-1.3
    metabolic acidosis / Delayed / 1.3-1.3
    hypomagnesemia / Delayed / 1.3-1.3
    hyperglycemia / Delayed / 1.3-1.3

    Mild

    nausea / Early / 2.1-40.2
    vomiting / Early / 2.1-27.8
    fever / Early / 0-23.3
    pruritus / Rapid / 0-15.0
    dizziness / Early / 0-11.3
    back pain / Delayed / 0-10.0
    insomnia / Early / 2.0-9.9
    muscle cramps / Delayed / 2.0-9.9
    headache / Early / 3.3-8.3
    dysgeusia / Early / 1.3-7.3
    abdominal pain / Early / 0-6.7
    drowsiness / Early / 0-5.2
    fatigue / Early / 4.2-5.0
    hyperhidrosis / Delayed / 0-4.7
    hypoesthesia / Delayed / 1.5-3.8
    diarrhea / Early / 3.8-3.8
    flatulence / Early / 3.8-3.8
    anxiety / Delayed / 0-3.0
    hiccups / Early / 1.3-2.4
    dyspepsia / Early / 1.3-2.3
    syncope / Early / 0-2.1
    anorexia / Delayed / 2.1-2.1
    weakness / Early / 0-2.0
    agitation / Early / 0-2.0
    paresthesias / Delayed / 0-2.0
    tinnitus / Delayed / 0-2.0
    restlessness / Early / 0-2.0
    tremor / Early / 0-2.0
    cough / Delayed / 0-2.0
    pallor / Early / 0-2.0
    urticaria / Rapid / 0-2.0
    rash / Early / 0-2.0
    injection site reaction / Rapid / 0-2.0
    musculoskeletal pain / Early / 0-2.0
    arthralgia / Delayed / 0-2.0
    infection / Delayed / 0-2.0
    asthenia / Delayed / 0-2.0
    lethargy / Early / 1.3-1.3
    diplopia / Early / 1.3-1.3
    metallic taste / Early / Incidence not known
    sneezing / Early / Incidence not known
    chills / Rapid / Incidence not known

    DRUG INTERACTIONS

    Acebutolol: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Acetaminophen: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Aspirin, ASA; Caffeine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Caffeine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Caffeine; Dihydrocodeine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Acetaminophen; Caffeine; Magnesium Salicylate; Phenyltoloxamine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Caffeine; Phenyltoloxamine; Salicylamide: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Chlorpheniramine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Chlorpheniramine; Dextromethorphan: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Chlorpheniramine; Dextromethorphan; Phenylephrine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Chlorpheniramine; Phenylephrine : (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Chlorpheniramine; Phenylephrine; Phenyltoloxamine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Codeine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Acetaminophen; Dextromethorphan: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Dextromethorphan; Doxylamine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Dextromethorphan; Guaifenesin; Phenylephrine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Dextromethorphan; Guaifenesin; Pseudoephedrine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Dextromethorphan; Phenylephrine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Dextromethorphan; Pseudoephedrine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Dichloralphenazone; Isometheptene: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Diphenhydramine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Guaifenesin; Phenylephrine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Hydrocodone: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Acetaminophen; Oxycodone: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Acetaminophen; Pamabrom; Pyrilamine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Pentazocine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Acetaminophen; Propoxyphene: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Acetaminophen; Pseudoephedrine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Alfentanil: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Ambenonium Chloride: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary.
    Aminosalicylate sodium, Aminosalicylic acid: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as aminosalicylic acid, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Amitriptyline: (Major) Coadminister bupivacaine and tricyclic antidepressants together with caution. If epinephrine is added to bupivacaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient.
    Amobarbital: (Minor) Bupivacaine is metabolized by CYP3A4. Barbiturates induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Amprenavir: (Minor) Bupivacaine is metabolized by cytochrome P450 (CYP) 3A4 isoenzymes. Known inhibitors of CYP 3A4, such as anti-retroviral protease inhibitors, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity. Although not studied, dosage adjustments of bupivacaine may be needed.
    Amyl Nitrite: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as nitrates, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Aprepitant, Fosaprepitant: (Moderate) Use caution if bupivacaine and aprepitant, fosaprepitant are used concurrently and monitor for an increase in bupivacaine-related adverse effects for several days after administration of a multi-day aprepitant regimen. In vitro, bupivacaine is a CYP3A4 substrate. Aprepitant, when administered as a 3-day oral regimen (125 mg/80 mg/80 mg), is a moderate CYP3A4 inhibitor and inducer and may increase plasma concentrations of bupivacaine. For example, a 5-day oral aprepitant regimen increased the AUC of another CYP3A4 substrate, midazolam (single dose), by 2.3-fold on day 1 and by 3.3-fold on day 5. After a 3-day oral aprepitant regimen, the AUC of midazolam (given on days 1, 4, 8, and 15) increased by 25% on day 4, and then decreased by 19% and 4% on days 8 and 15, respectively. As a single 125 mg or 40 mg oral dose, the inhibitory effect of aprepitant on CYP3A4 is weak, with the AUC of midazolam increased by 1.5-fold and 1.2-fold, respectively. After administration, fosaprepitant is rapidly converted to aprepitant and shares many of the same drug interactions. However, as a single 150 mg intravenous dose, fosaprepitant only weakly inhibits CYP3A4 for a duration of 2 days; there is no evidence of CYP3A4 induction. Fosaprepitant 150 mg IV as a single dose increased the AUC of midazolam (given on days 1 and 4) by approximately 1.8-fold on day 1; there was no effect on day 4. Less than a 2-fold increase in the midazolam AUC is not considered clinically important.
    Articaine; Epinephrine: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Use articaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Aspirin, ASA; Butalbital; Caffeine: (Minor) Bupivacaine is metabolized by CYP3A4. Barbiturates induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Aspirin, ASA; Butalbital; Caffeine; Codeine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation. (Minor) Bupivacaine is metabolized by CYP3A4. Barbiturates induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Aspirin, ASA; Caffeine; Dihydrocodeine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Aspirin, ASA; Carisoprodol; Codeine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Aspirin, ASA; Oxycodone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Atazanavir: (Moderate) Atazanavir inhibits the CYP3A4 isoenzyme at clinically relevant concentrations, which may lead to increased serum concentrations of local anesthetics and an increased potential for QT prolongation or other adverse effects.
    Atazanavir; Cobicistat: (Moderate) Atazanavir inhibits the CYP3A4 isoenzyme at clinically relevant concentrations, which may lead to increased serum concentrations of local anesthetics and an increased potential for QT prolongation or other adverse effects. (Minor) Plasma concentrations of bupivacaine may be elevated when administered concurrently with cobicistat. Clinical monitoring for adverse effects, such as cardiotoxic effects, hypotension, or CNS toxicity, is recommended during coadministration. Cobicistat is a CYP3A4 inhibitor, while bupivacaine is a CYP3A4 substrate.
    Atenolol: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Atenolol; Chlorthalidone: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Atracurium: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
    Atropine; Edrophonium: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary.
    Barbiturates: (Minor) Bupivacaine is metabolized by CYP3A4. Barbiturates induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Belladonna Alkaloids; Ergotamine; Phenobarbital: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient taking ergot alkaloids. Severe hypertension that may be persistent or a cerebrovascular accident can result from concomitant use of a vasopressor and an ergot type oxytocic drug. (Minor) Bupivacaine is metabolized by CYP3A4. Barbiturates induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Belladonna; Opium: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Bendroflumethiazide; Nadolol: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Benzalkonium Chloride; Benzocaine: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Use benzocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Benzhydrocodone; Acetaminophen: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Benzocaine: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Use benzocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Benzocaine; Butamben; Tetracaine: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Use benzocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Betaxolol: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Bisoprolol: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Bisoprolol; Hydrochlorothiazide, HCTZ: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Boceprevir: (Moderate) Close clinical monitoring is advised when administering bupivacaine with boceprevir due to an increased potential for bupivacaine-related adverse events. If bupivacaine dose adjustments are made, re-adjust the dose upon completion of boceprevir treatment. Although this interaction has not been studied, predictions about the interaction can be made based on the metabolic pathway of bupivacaine. Bupivacaine is metabolized by the hepatic isoenzyme CYP3A4; boceprevir inhibits this isoenzyme. Coadministration may result in elevated bupivacaine plasma concentrations.
    Brimonidine; Timolol: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Brompheniramine; Guaifenesin; Hydrocodone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Brompheniramine; Hydrocodone; Pseudoephedrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Bupivacaine; Lidocaine: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Liposomal bupivacaine administration may follow lidocaine administration after a delay of 20 minutes or more. Use lidocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Butabarbital: (Minor) Bupivacaine is metabolized by CYP3A4. Barbiturates induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Butalbital; Acetaminophen: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Minor) Bupivacaine is metabolized by CYP3A4. Barbiturates induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Butalbital; Acetaminophen; Caffeine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Minor) Bupivacaine is metabolized by CYP3A4. Barbiturates induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Butalbital; Acetaminophen; Caffeine; Codeine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation. (Minor) Bupivacaine is metabolized by CYP3A4. Barbiturates induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Carbamazepine: (Minor) Bupivacaine is metabolized by CYP3A4. Carbamazepine induces these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Carbinoxamine; Hydrocodone; Phenylephrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Carbinoxamine; Hydrocodone; Pseudoephedrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Carteolol: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Carvedilol: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Chlordiazepoxide; Amitriptyline: (Major) Coadminister bupivacaine and tricyclic antidepressants together with caution. If epinephrine is added to bupivacaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient.
    Chloroprocaine: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Use chloroprocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Chloroquine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as chloroquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Chlorpheniramine; Codeine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Chlorpheniramine; Dihydrocodeine; Phenylephrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Chlorpheniramine; Dihydrocodeine; Pseudoephedrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Chlorpheniramine; Guaifenesin; Hydrocodone; Pseudoephedrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Chlorpheniramine; Hydrocodone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Chlorpheniramine; Hydrocodone; Phenylephrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Chlorpheniramine; Hydrocodone; Pseudoephedrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Cholinesterase inhibitors: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary.
    Ciprofloxacin: (Moderate) Clinical monitoring for adverse effects, such as cardiotoxic effects, hypotension, or CNS toxicity, is recommended during coadministration as plasma concentrations of bupivacaine may be elevated when administered concurrently with ciprofloxacin. Ciprofloxacin is a CYP3A4 inhibitor, while bupivacaine is a CYP3A4 substrate.
    Cisatracurium: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
    Clomipramine: (Major) Coadminister bupivacaine and tricyclic antidepressants together with caution. If epinephrine is added to bupivacaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient.
    Cobicistat: (Minor) Plasma concentrations of bupivacaine may be elevated when administered concurrently with cobicistat. Clinical monitoring for adverse effects, such as cardiotoxic effects, hypotension, or CNS toxicity, is recommended during coadministration. Cobicistat is a CYP3A4 inhibitor, while bupivacaine is a CYP3A4 substrate.
    Codeine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Codeine; Guaifenesin: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Codeine; Guaifenesin; Pseudoephedrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Codeine; Phenylephrine; Promethazine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Codeine; Promethazine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Conivaptan: (Major) According to the manufacturer, concomitant use of conivaptan, a strong CYP3A4 inhibitor, and CYP3A substrates, such as bupivacaine, should be avoided. Coadministration of conivaptan with other CYP3A substrates has resulted in increased mean AUC values (2 to 3 times). Theoretically, similar pharmacokinetic effects could be seen with bupivacaine. Treatment with bupivacaine may be initiated no sooner than 1 week after completion of conivaptan therapy.
    Cyclophosphamide: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as cyclophosphamide, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Dapsone: (Moderate) Coadministration of dapsone with bupivacaine may increase the risk of developing methemoglobinemia. Advise patients to discontinue treatment and seek immediate medical attention with any signs or symptoms of methemoglobinemia.
    Daratumumab; Hyaluronidase: (Moderate) Hyaluronidase, when used in combination with local anesthetics, hastens the onset of analgesia and reduces the swelling caused by local infiltration; this interaction is beneficial and is the reason hyaluronidase is used adjunctively in local infiltrative anesthesia techniques. However, the wider spread of the local anesthetic solution may increase the systemic absorption of the local anesthetic, which shortens the duration of anesthetic action and tends to increase the potential risk for systemic side effects.
    Darunavir: (Minor) Bupivacaine is metabolized by cytochrome P450 (CYP) 3A4 isoenzymes. Known inhibitors of CYP 3A4, such as anti-retroviral protease inhibitors, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity. Although not studied, dosage adjustments of bupivacaine may be needed.
    Darunavir; Cobicistat: (Minor) Bupivacaine is metabolized by cytochrome P450 (CYP) 3A4 isoenzymes. Known inhibitors of CYP 3A4, such as anti-retroviral protease inhibitors, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity. Although not studied, dosage adjustments of bupivacaine may be needed. (Minor) Plasma concentrations of bupivacaine may be elevated when administered concurrently with cobicistat. Clinical monitoring for adverse effects, such as cardiotoxic effects, hypotension, or CNS toxicity, is recommended during coadministration. Cobicistat is a CYP3A4 inhibitor, while bupivacaine is a CYP3A4 substrate.
    Darunavir; Cobicistat; Emtricitabine; Tenofovir alafenamide: (Minor) Bupivacaine is metabolized by cytochrome P450 (CYP) 3A4 isoenzymes. Known inhibitors of CYP 3A4, such as anti-retroviral protease inhibitors, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity. Although not studied, dosage adjustments of bupivacaine may be needed. (Minor) Plasma concentrations of bupivacaine may be elevated when administered concurrently with cobicistat. Clinical monitoring for adverse effects, such as cardiotoxic effects, hypotension, or CNS toxicity, is recommended during coadministration. Cobicistat is a CYP3A4 inhibitor, while bupivacaine is a CYP3A4 substrate.
    Dasabuvir; Ombitasvir; Paritaprevir; Ritonavir: (Minor) Bupivacaine is metabolized by cytochrome P450 (CYP) 3A4 isoenzymes. Known inhibitors of CYP 3A4, such as anti-retroviral protease inhibitors, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity. Although not studied, dosage adjustments of bupivacaine may be needed.
    Delavirdine: (Minor) Bupivacaine is metabolized by CYP3A4 isoenzymes. Known inhibitors of CYP3A4, such as delavirdine, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity.
    Desipramine: (Major) Coadminister bupivacaine and tricyclic antidepressants together with caution. If epinephrine is added to bupivacaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient.
    Dihydrocodeine; Guaifenesin; Pseudoephedrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Dihydroergotamine: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient taking ergot alkaloids. Severe hypertension that may be persistent or a cerebrovascular accident can result from concomitant use of a vasopressor and an ergot type oxytocic drug.
    Diltiazem: (Moderate) Diltiazem may inhibit the CYP3A4-mediated metabolism of bupivacaine. Use caution when administering these drugs concomitantly.
    Diphenhydramine; Hydrocodone; Phenylephrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Donepezil: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary.
    Donepezil; Memantine: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary.
    Dorzolamide; Timolol: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Doxacurium: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
    Doxepin: (Major) Coadminister bupivacaine and tricyclic antidepressants together with caution. If epinephrine is added to bupivacaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient.
    Edrophonium: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary.
    Elbasvir; Grazoprevir: (Moderate) Administering bupivacaine with elbasvir; grazoprevir may result in elevated bupivacaine plasma concentrations. Bupivacaine is a substrate of CYP3A; grazoprevir is a weak CYP3A inhibitor. If these drugs are used together, closely monitor for signs of adverse events.
    Elvitegravir; Cobicistat; Emtricitabine; Tenofovir Alafenamide: (Minor) Plasma concentrations of bupivacaine may be elevated when administered concurrently with cobicistat. Clinical monitoring for adverse effects, such as cardiotoxic effects, hypotension, or CNS toxicity, is recommended during coadministration. Cobicistat is a CYP3A4 inhibitor, while bupivacaine is a CYP3A4 substrate.
    Elvitegravir; Cobicistat; Emtricitabine; Tenofovir Disoproxil Fumarate: (Minor) Plasma concentrations of bupivacaine may be elevated when administered concurrently with cobicistat. Clinical monitoring for adverse effects, such as cardiotoxic effects, hypotension, or CNS toxicity, is recommended during coadministration. Cobicistat is a CYP3A4 inhibitor, while bupivacaine is a CYP3A4 substrate.
    Enflurane: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient during or following treatment with general anesthetics. Concurrent use has been associated with the development of cardiac arrhythmias, and should be avoided, if possible.
    Ergoloid Mesylates: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient taking ergot alkaloids. Severe hypertension that may be persistent or a cerebrovascular accident can result from concomitant use of a vasopressor and an ergot type oxytocic drug.
    Ergonovine: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient taking ergot alkaloids. Severe hypertension that may be persistent or a cerebrovascular accident can result from concomitant use of a vasopressor and an ergot type oxytocic drug.
    Ergot alkaloids: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient taking ergot alkaloids. Severe hypertension that may be persistent or a cerebrovascular accident can result from concomitant use of a vasopressor and an ergot type oxytocic drug.
    Ergotamine: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient taking ergot alkaloids. Severe hypertension that may be persistent or a cerebrovascular accident can result from concomitant use of a vasopressor and an ergot type oxytocic drug.
    Ergotamine; Caffeine: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient taking ergot alkaloids. Severe hypertension that may be persistent or a cerebrovascular accident can result from concomitant use of a vasopressor and an ergot type oxytocic drug.
    Erythromycin; Sulfisoxazole: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as sulfonamides, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Esmolol: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Etomidate: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient during or following treatment with general anesthetics. Concurrent use has been associated with the development of cardiac arrhythmias, and should be avoided, if possible.
    Fentanyl: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for epidural analgesia or additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Fluconazole: (Minor) Bupivacaine is metabolized by CYP3A4 isoenzymes. Known inhibitors of CYP3A4, such as fluconazole, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity.
    Fluoxetine: (Minor) Bupivacaine is metabolized by CYP3A4 isoenzymes. Known inhibitors of CYP3A4, such as fluoxetine, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity.
    Flutamide: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as flutamide, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Fluvoxamine: (Minor) Bupivacaine is metabolized by CYP3A4 isoenzymes. Known inhibitors of CYP3A4, such as fluvoxamine, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity.
    Fosamprenavir: (Minor) Bupivacaine is metabolized by cytochrome P450 (CYP) 3A4 isoenzymes. Known inhibitors of CYP 3A4, such as anti-retroviral protease inhibitors, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity. Although not studied, dosage adjustments of bupivacaine may be needed.
    Fospropofol: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient during or following treatment with general anesthetics. Concurrent use has been associated with the development of cardiac arrhythmias, and should be avoided, if possible.
    Galantamine: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary.
    General anesthetics: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient during or following treatment with general anesthetics. Concurrent use has been associated with the development of cardiac arrhythmias, and should be avoided, if possible.
    Guaifenesin; Hydrocodone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Guaifenesin; Hydrocodone; Pseudoephedrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Halothane: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient during or following treatment with general anesthetics. Concurrent use has been associated with the development of cardiac arrhythmias, and should be avoided, if possible.
    Homatropine; Hydrocodone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Hyaluronidase, Recombinant; Immune Globulin: (Moderate) Hyaluronidase, when used in combination with local anesthetics, hastens the onset of analgesia and reduces the swelling caused by local infiltration; this interaction is beneficial and is the reason hyaluronidase is used adjunctively in local infiltrative anesthesia techniques. However, the wider spread of the local anesthetic solution may increase the systemic absorption of the local anesthetic, which shortens the duration of anesthetic action and tends to increase the potential risk for systemic side effects.
    Hyaluronidase: (Moderate) Hyaluronidase, when used in combination with local anesthetics, hastens the onset of analgesia and reduces the swelling caused by local infiltration; this interaction is beneficial and is the reason hyaluronidase is used adjunctively in local infiltrative anesthesia techniques. However, the wider spread of the local anesthetic solution may increase the systemic absorption of the local anesthetic, which shortens the duration of anesthetic action and tends to increase the potential risk for systemic side effects.
    Hydantoins: (Minor) Bupivacaine is metabolized by CYP3A4. Hydantoins induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Hydralazine; Isosorbide Dinitrate, ISDN: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as nitrates, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Hydrocodone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Hydrocodone; Ibuprofen: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Hydrocodone; Phenylephrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Hydrocodone; Potassium Guaiacolsulfonate: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Hydrocodone; Potassium Guaiacolsulfonate; Pseudoephedrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Hydrocodone; Pseudoephedrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Hydromorphone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Hydroxyurea: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as hydroxyurea, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Ibuprofen; Oxycodone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Idelalisib: (Major) Avoid concomitant use of idelalisib, a strong CYP3A inhibitor, with bupivacaine, a CYP3A substrate, as bupivacaine toxicities may be significantly increased. The AUC of a sensitive CYP3A substrate was increased 5.4-fold when coadministered with idelalisib.
    Ifosfamide: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as ifosfamide, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Imatinib: (Minor) Bupivacaine is metabolized by CYP3A4 isoenzymes. Known inhibitors of CYP3A4, such as imatinib, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity.
    Imipramine: (Major) Coadminister bupivacaine and tricyclic antidepressants together with caution. If epinephrine is added to bupivacaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient.
    Indinavir: (Minor) Bupivacaine is metabolized by cytochrome P450 (CYP) 3A4 isoenzymes. Known inhibitors of CYP 3A4, such as anti-retroviral protease inhibitors, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity. Although not studied, dosage adjustments of bupivacaine may be needed.
    Isavuconazonium: (Moderate) Concomitant use of isavuconazonium with bupivacaine may result in increased serum concentrations of bupivacaine. Bupivacaine is a substrate of the hepatic isoenzyme CYP3A4; isavuconazole, the active moiety of isavuconazonium, is a moderate inhibitor of this enzyme. Caution and close monitoring are advised if these drugs are used together.
    Isocarboxazid: (Major) Patients receiving local anesthetics may have an increased risk of hypotension. Combined hypotensive effects are possible with use of MAOIs and spinal anesthetics. When local anesthetics containing sympathomimetic vasoconstrictors (e.g., epinephrine) are coadministered with MAOIs, severe and prolonged hypertension may occur. MAOIs can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Phenelzine and tranylcypromine are contraindicated for use for at least 10 days prior to elective surgery.
    Isoflurane: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient during or following treatment with general anesthetics. Concurrent use has been associated with the development of cardiac arrhythmias, and should be avoided, if possible.
    Isosorbide Dinitrate, ISDN: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as nitrates, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Isosorbide Mononitrate: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as nitrates, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Itraconazole: (Moderate) Itraconazole causes a modest increase in bupivacaine serum concentrations. It is unclear if this increase is due to CYP3A4 inhibition by itraconazole or if other mechanisms are involved.
    Ketamine: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient during or following treatment with general anesthetics. Concurrent use has been associated with the development of cardiac arrhythmias, and should be avoided, if possible.
    Ketoconazole: (Minor) Bupivacaine is metabolized by CYP3A4 isoenzymes. Known inhibitors of CYP3A4, such as ketoconazole, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity.
    Labetalol: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Lamotrigine: (Moderate) Consider ECG monitoring before and during concomitant use of lamotrigine with other sodium channel blockers known to impair atrioventricular and/or intraventricular cardiac conduction, such as bupivacaine. Concomitant use of bupivacaine with lamotrigine may increase the risk of proarrhythmia, especially in patients with clinically important structural or functional heart disease. In vitro testing showed that lamotrigine exhibits class IB antiarrhythmic activity at therapeutically relevant concentrations.
    Lesinurad: (Moderate) Lesinurad may decrease the systemic exposure and therapeutic efficacy of bupivacaine; monitor for potential reduction in efficacy. Bupivacaine is a CYP3A substrate, and lesinurad is a weak CYP3A inducer.
    Lesinurad; Allopurinol: (Moderate) Lesinurad may decrease the systemic exposure and therapeutic efficacy of bupivacaine; monitor for potential reduction in efficacy. Bupivacaine is a CYP3A substrate, and lesinurad is a weak CYP3A inducer.
    Levoketoconazole: (Minor) Bupivacaine is metabolized by CYP3A4 isoenzymes. Known inhibitors of CYP3A4, such as ketoconazole, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity.
    Levomethadyl: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Levorphanol: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Lidocaine: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Liposomal bupivacaine administration may follow lidocaine administration after a delay of 20 minutes or more. Use lidocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Lidocaine; Epinephrine: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Liposomal bupivacaine administration may follow lidocaine administration after a delay of 20 minutes or more. Use lidocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Lidocaine; Prilocaine: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Liposomal bupivacaine administration may follow lidocaine administration after a delay of 20 minutes or more. Use lidocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Use prilocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Lopinavir; Ritonavir: (Minor) Bupivacaine is metabolized by cytochrome P450 (CYP) 3A4 isoenzymes. Known inhibitors of CYP 3A4, such as anti-retroviral protease inhibitors, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity. Although not studied, dosage adjustments of bupivacaine may be needed.
    Magnesium Salts: (Minor) Because of the CNS-depressant effects of magnesium sulfate, additive central-depressant effects can occur following concurrent administration with CNS depressants such as local anesthetics. Caution should be exercised when using these agents concurrently.
    Meperidine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Meperidine; Promethazine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Mephobarbital: (Minor) Bupivacaine is metabolized by CYP3A4. Barbiturates induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Mepivacaine: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Use mepivacaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Mepivacaine; Levonordefrin: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Use mepivacaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Methadone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Methohexital: (Minor) Bupivacaine is metabolized by CYP3A4. Barbiturates induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Methylergonovine: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient taking ergot alkaloids. Severe hypertension that may be persistent or a cerebrovascular accident can result from concomitant use of a vasopressor and an ergot type oxytocic drug.
    Methysergide: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient taking ergot alkaloids. Severe hypertension that may be persistent or a cerebrovascular accident can result from concomitant use of a vasopressor and an ergot type oxytocic drug.
    Metoclopramide: (Moderate) Coadministration of bupivacaine with metoclopramide may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other agents associated with methemoglobinemia. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Metoprolol: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Metoprolol; Hydrochlorothiazide, HCTZ: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Minocycline: (Moderate) Injectable minocycline contains magnesium sulfate heptahydrate. Because of the CNS-depressant effects of magnesium sulfate, additive central-depressant effects can occur following concurrent administration with CNS depressants such as local anesthetics. Caution should be exercised when using these agents concurrently.
    Mitotane: (Moderate) Use caution if mitotane and bupivacaine are used concomitantly, and monitor for decreased efficacy of bupivacaine and a possible change in dosage requirements. Mitotane is a strong CYP3A4 inducer and bupivacaine is a CYP3A4 substrate in vitro; coadministration may result in decreased plasma concentrations of bupivacaine.
    Mivacurium: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
    Monoamine oxidase inhibitors: (Major) Patients receiving local anesthetics may have an increased risk of hypotension. Combined hypotensive effects are possible with use of MAOIs and spinal anesthetics. When local anesthetics containing sympathomimetic vasoconstrictors (e.g., epinephrine) are coadministered with MAOIs, severe and prolonged hypertension may occur. MAOIs can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Phenelzine and tranylcypromine are contraindicated for use for at least 10 days prior to elective surgery.
    Morphine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Morphine; Naltrexone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Nadolol: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Nebivolol: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Nebivolol; Valsartan: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Nefazodone: (Minor) Bupivacaine is metabolized by CYP3A4 isoenzymes. Known inhibitors of CYP3A4, such as nefazodone, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity.
    Nelfinavir: (Minor) Bupivacaine is metabolized by cytochrome P450 (CYP) 3A4 isoenzymes. Known inhibitors of CYP 3A4, such as anti-retroviral protease inhibitors, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity. Although not studied, dosage adjustments of bupivacaine may be needed.
    Neostigmine: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary.
    Neuromuscular blockers: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
    Nevirapine: (Minor) Bupivacaine is metabolized by CYP3A4. Nevirapine induces these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Nirmatrelvir; Ritonavir: (Minor) Bupivacaine is metabolized by cytochrome P450 (CYP) 3A4 isoenzymes. Known inhibitors of CYP 3A4, such as anti-retroviral protease inhibitors, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity. Although not studied, dosage adjustments of bupivacaine may be needed.
    Nitrates: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as nitrates, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Nitrofurantoin: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as nitrofurantoin, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Nitroglycerin: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as nitrates, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Nortriptyline: (Major) Coadminister bupivacaine and tricyclic antidepressants together with caution. If epinephrine is added to bupivacaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient.
    Olanzapine; Fluoxetine: (Minor) Bupivacaine is metabolized by CYP3A4 isoenzymes. Known inhibitors of CYP3A4, such as fluoxetine, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity.
    Ombitasvir; Paritaprevir; Ritonavir: (Minor) Bupivacaine is metabolized by cytochrome P450 (CYP) 3A4 isoenzymes. Known inhibitors of CYP 3A4, such as anti-retroviral protease inhibitors, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity. Although not studied, dosage adjustments of bupivacaine may be needed.
    Oritavancin: (Minor) Bupivacaine is metabolized by CYP3A4; oritavancin is a weak CYP3A4 inducer. Plasma concentrations and efficacy of bupivacaine may be reduced if these drugs are administered concurrently.
    Oxycodone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Oxymorphone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Pancuronium: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
    Pazopanib: (Moderate) Pazopanib is a weak inhibitor of CYP3A4. Coadministration of pazopanib and bupivacaine, a CYP3A4 substrate, may cause an increase in systemic concentrations of bupivacaine. Use caution when administering these drugs concomitantly.
    Penbutolol: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Penicillin G Benzathine; Penicillin G Procaine: (Moderate) Coadministration of penicillin G procaine with other local anesthetics, such as bupivacaine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue penicillin G procaine and any other local anesthetic. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Penicillin G Procaine: (Moderate) Coadministration of penicillin G procaine with other local anesthetics, such as bupivacaine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue penicillin G procaine and any other local anesthetic. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Pentobarbital: (Minor) Bupivacaine is metabolized by CYP3A4. Barbiturates induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Pergolide: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient taking ergot alkaloids. Severe hypertension that may be persistent or a cerebrovascular accident can result from concomitant use of a vasopressor and an ergot type oxytocic drug.
    Perphenazine; Amitriptyline: (Major) Coadminister bupivacaine and tricyclic antidepressants together with caution. If epinephrine is added to bupivacaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient.
    Pertuzumab; Trastuzumab; Hyaluronidase: (Moderate) Hyaluronidase, when used in combination with local anesthetics, hastens the onset of analgesia and reduces the swelling caused by local infiltration; this interaction is beneficial and is the reason hyaluronidase is used adjunctively in local infiltrative anesthesia techniques. However, the wider spread of the local anesthetic solution may increase the systemic absorption of the local anesthetic, which shortens the duration of anesthetic action and tends to increase the potential risk for systemic side effects.
    Phenelzine: (Major) Patients receiving local anesthetics may have an increased risk of hypotension. Combined hypotensive effects are possible with use of MAOIs and spinal anesthetics. When local anesthetics containing sympathomimetic vasoconstrictors (e.g., epinephrine) are coadministered with MAOIs, severe and prolonged hypertension may occur. MAOIs can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Phenelzine and tranylcypromine are contraindicated for use for at least 10 days prior to elective surgery.
    Phenobarbital: (Minor) Bupivacaine is metabolized by CYP3A4. Barbiturates induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Phenobarbital; Hyoscyamine; Atropine; Scopolamine: (Minor) Bupivacaine is metabolized by CYP3A4. Barbiturates induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Physostigmine: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary.
    Pindolol: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Posaconazole: (Moderate) Posaconazole and bupivacaine should be coadministered with caution due to an increased potential for bupivacaine-related adverse events. Posaconazole is a potent inhibitor of CYP3A4, an isoenzyme responsible for the metabolism of bupivacaine. These drugs used in combination may result in elevated bupivacaine plasma concentrations, causing an increased risk for bupivacaine related adverse events.
    Povidone-Iodine: (Moderate) Bupivacaine liposomal should not come into contact with topical antiseptics (e.g., povidone-iodine). If a topical antiseptic is applied to the surgical site, allow the site to dry completely before administering bupivacaine liposomal.
    Prilocaine: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Use prilocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Prilocaine; Epinephrine: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Use prilocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Primaquine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Primidone: (Minor) Bupivacaine is metabolized by CYP3A4. Barbiturates induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Procarbazine: (Major) Patients taking procarbazine should not be given local anesthetics containing sympathomimetic vasoconstrictors; coadministration may invoke a severe hypertensive reaction. Procarbazine should be discontinued for at least 10 days prior to elective surgery.
    Propofol: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient during or following treatment with general anesthetics. Concurrent use has been associated with the development of cardiac arrhythmias, and should be avoided, if possible.
    Propoxyphene: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Propranolol: (Major) Propranolol has been shown to significantly decrease the clearance of the amide local anesthetics (e.g., lidocaine, bupivacaine, and mepivacaine). Lidocaine and bupivacaine toxicity have been reported after coadministration with propranolol. The mechanism of the interaction between propranolol and lidocaine is thought to be due to propranolol-induced decreased hepatic blood flow causing decreased elimination of lidocaine. Local anesthetics may also cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents or rapid-onset vasodilators, such as nitrates. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Propranolol; Hydrochlorothiazide, HCTZ: (Major) Propranolol has been shown to significantly decrease the clearance of the amide local anesthetics (e.g., lidocaine, bupivacaine, and mepivacaine). Lidocaine and bupivacaine toxicity have been reported after coadministration with propranolol. The mechanism of the interaction between propranolol and lidocaine is thought to be due to propranolol-induced decreased hepatic blood flow causing decreased elimination of lidocaine. Local anesthetics may also cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents or rapid-onset vasodilators, such as nitrates. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Protriptyline: (Major) Coadminister bupivacaine and tricyclic antidepressants together with caution. If epinephrine is added to bupivacaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient.
    Pyridostigmine: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary.
    Pyrimethamine; Sulfadoxine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as sulfonamides, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Quinine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as quinine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Rapacuronium: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
    Rasburicase: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as rasburicase, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Remifentanil: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Ritonavir: (Minor) Bupivacaine is metabolized by cytochrome P450 (CYP) 3A4 isoenzymes. Known inhibitors of CYP 3A4, such as anti-retroviral protease inhibitors, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity. Although not studied, dosage adjustments of bupivacaine may be needed.
    Rituximab; Hyaluronidase: (Moderate) Hyaluronidase, when used in combination with local anesthetics, hastens the onset of analgesia and reduces the swelling caused by local infiltration; this interaction is beneficial and is the reason hyaluronidase is used adjunctively in local infiltrative anesthesia techniques. However, the wider spread of the local anesthetic solution may increase the systemic absorption of the local anesthetic, which shortens the duration of anesthetic action and tends to increase the potential risk for systemic side effects.
    Rivastigmine: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary.
    Rocuronium: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
    Ropivacaine: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Use other formulations of bupivacaine and ropivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Secobarbital: (Minor) Bupivacaine is metabolized by CYP3A4. Barbiturates induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Sevoflurane: (Major) If epinephrine is added to bupivacaine, do not use the mixture in a patient during or following treatment with general anesthetics. Concurrent use has been associated with the development of cardiac arrhythmias, and should be avoided, if possible.
    Simeprevir: (Moderate) Simeprevir, a mild intestinal CYP3A4 inhibitor, may increase the side effects of bupivacaine, which is a CYP3A4 substrate. Monitor patients for adverse effects of bupivacaine, such as CNS or respiratory depression.
    Sodium Sulfate; Magnesium Sulfate; Potassium Chloride: (Minor) Because of the CNS-depressant effects of magnesium sulfate, additive central-depressant effects can occur following concurrent administration with CNS depressants such as local anesthetics. Caution should be exercised when using these agents concurrently.
    Succinylcholine: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
    Sufentanil: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
    Sulfadiazine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as sulfonamides, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Sulfamethoxazole; Trimethoprim, SMX-TMP, Cotrimoxazole: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as sulfonamides, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Sulfasalazine: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as sulfonamides, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Sulfisoxazole: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as sulfonamides, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Sulfonamides: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as sulfonamides, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Tacrine: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary.
    Telaprevir: (Moderate) Close clinical monitoring is advised when administering bupivacaine with telaprevir due to an increased potential for bupivacaine-related adverse events. If bupivacaine dose adjustments are made, re-adjust the dose upon completion of telaprevir treatment. Although this interaction has not been studied, predictions about the interaction can be made based on the metabolic pathway of bupivacaine. Bupivacaine is metabolized by the hepatic isoenzyme CYP3A4; telaprevir inhibits this isoenzyme. Coadministration may result in elevated bupivacaine plasma concentrations.
    Telithromycin: (Moderate) Telithromycin is an inhibitor of and bupivacaine is a substrate of the CYP3A4 isoenzyme; therefore, coadministration may lead to increased concentrations of bupivicaine.
    Tetracaine: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Use tetracaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Thiopental: (Minor) Bupivacaine is metabolized by CYP3A4. Barbiturates induce these isoenzymes and if given concurrently with bupivacaine may decrease the efficacy of bupivacaine.
    Timolol: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of bupivacaine and antihypertensive agents. Peripheral vasodilation may occur after use of bupivacaine. Thus, patients receiving antihypertensive agents may experience additive hypotensive effects. Blood concentrations of local anesthetics achieved after therapeutic doses are associated with minimal change in peripheral vascular resistance. Higher blood concentrations of local anesthetics may occur due to inadvertent intravascular administration or repeated doses.
    Tipranavir: (Minor) Bupivacaine is metabolized by cytochrome P450 (CYP) 3A4 isoenzymes. Known inhibitors of CYP 3A4, such as anti-retroviral protease inhibitors, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity. Although not studied, dosage adjustments of bupivacaine may be needed.
    Tramadol; Acetaminophen: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Trandolapril; Verapamil: (Moderate) Verapamil may inhibit the CYP3A4-mediated metabolism of and bupivacaine. Use caution when administering these drugs concomitantly.
    Tranylcypromine: (Major) Patients receiving local anesthetics may have an increased risk of hypotension. Combined hypotensive effects are possible with use of MAOIs and spinal anesthetics. When local anesthetics containing sympathomimetic vasoconstrictors (e.g., epinephrine) are coadministered with MAOIs, severe and prolonged hypertension may occur. MAOIs can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Phenelzine and tranylcypromine are contraindicated for use for at least 10 days prior to elective surgery.
    Trastuzumab; Hyaluronidase: (Moderate) Hyaluronidase, when used in combination with local anesthetics, hastens the onset of analgesia and reduces the swelling caused by local infiltration; this interaction is beneficial and is the reason hyaluronidase is used adjunctively in local infiltrative anesthesia techniques. However, the wider spread of the local anesthetic solution may increase the systemic absorption of the local anesthetic, which shortens the duration of anesthetic action and tends to increase the potential risk for systemic side effects.
    Tricyclic antidepressants: (Major) Coadminister bupivacaine and tricyclic antidepressants together with caution. If epinephrine is added to bupivacaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient.
    Trimipramine: (Major) Coadminister bupivacaine and tricyclic antidepressants together with caution. If epinephrine is added to bupivacaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient.
    Tubocurarine: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
    Valproic Acid, Divalproex Sodium: (Moderate) Coadministration of bupivacaine with oxidizing agents, such as valproic acid, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue bupivacaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
    Vecuronium: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
    Verapamil: (Moderate) Verapamil may inhibit the CYP3A4-mediated metabolism of and bupivacaine. Use caution when administering these drugs concomitantly.
    Voriconazole: (Minor) Bupivacaine is metabolized by CYP3A4 isoenzymes. Known inhibitors of CYP3A4, such as voriconazole, may result in increased systemic levels of bupivacaine when given concurrently, with potential for toxicity.

    PREGNANCY AND LACTATION

    Pregnancy

    Limited data indicate that bupivacaine and its metabolite, pipecoloxylidide, are present in human milk at low concentrations. There are no data on the effects of bupivacaine on the breast-fed infant or on milk production. Consider the developmental and health benefits of breast-feeding along with the mother's clinical need for liposomal bupivacaine and any potential adverse effects on the breast-fed infant from liposomal bupivacaine or from the underlying maternal condition.[46598] In general, use of local anesthetics during surgery or other procedures allows breast-feeding of the healthy term infant to be permissible as soon as the mother is awake and alert.[46104] In a study of 27 pregnant women undergoing cesarean delivery, administration of epidural anesthesia with 0.5% bupivacaine and 2% lidocaine during delivery had no effect on the breast-fed infant.[49514] A prospective cohort study comparing women who received no analgesia (n = 63) to women who received continuous epidural fentanyl and either bupivacaine 0.05% to 0.1% (n = 39) or ropivacaine (n = 13) during labor and delivery found no differences between the groups in breast-feeding effectiveness or infant neurobehavioral status at 8 to 12 hours postpartum.[49516] In 30 patients who underwent elective cesarean delivery, epidural bupivacaine use as part of a postoperative pain management regimen (n = 15) did not result in any significant difference to the time when breast-feeding started compared to spinal anesthesia alone (2.4 vs. 2.5 days).[60471]

    MECHANISM OF ACTION

    Like all local anesthetics, bupivacaine causes a reversible nerve-conduction blockade by increasing the threshold for electrical stimulation in the nerve, by slowing the propagation of the nerve impulse, and by reducing the rate of the action potential. The progression of anesthesia is directly related to the diameter, myelination, and conduction velocity of the affected nerve. Loss of nerve function clinically is as follows: pain, temperature, touch, proprioception, and skeletal muscle tone.]

    PHARMACOKINETICS

    Bupivacaine liposomal is administered by local infiltration into the surgical site or by interscalene nerve block. Upon release of bupivacaine from the liposomal complex and subsequent systemic absorption, bupivacaine distribution and excretion is expected to be the same as for bupivacaine hydrochloride solution. Specifically, bupivacaine is distributed to all tissues, with a high concentration in well-perfused organs such as the liver, lung, heart, and brain. Bupivacaine is highly protein bound (95%), lipid soluble, non-ionized, and crosses the placenta by passive diffusion. It has a low fetal/maternal ratio (0.2 to 0.4). Bupivacaine is metabolized primarily in the liver via conjugation with glucuronic acid. Approximately 5% of bupivacaine is converted to pipecolylxylidine, which is the major metabolite of bupivacaine. Elimination is dependent on the availability of plasma protein binding sites in the circulation to carry it to the liver for metabolism. Bupivacaine is excreted renally; approximately 6% is excreted as unchanged drug. Acidifying the urine quickens excretion.

    Other Route(s)

    Regional Route
    Systemic plasma concentrations of liposomal bupivacaine may persist for up to 96 hours after local infiltration and 120 hours after interscalene brachial plexus nerve block. Systemic concentrations do not correlate with local efficacy. The rate of absorption is dependent upon total dose administered, route of administration, and vascularity of the administration site. With local infiltration, exposure is greater during hemorrhoidectomy compared to bunionectomy. The Cmax and Tmax observed after hemorrhoidectomy (266 mg administered) and bunionectomy (106 mg administered) are 867 ng/mL and 0.5 hours and 166 ng/mL and 2 hours, respectively. The half-life of bupivacaine is higher when used for bunionectomy compared to hemorrhoidectomy (31.4 hours vs. 23.8 hours). Cmax and Tmax of liposomal bupivacaine were 207 ng/mL and 48 hours, respectively, with interscalene brachial plexus nerve block after total shoulder arthroplasty. The half-life of liposomal bupivacaine in this setting and population was 11 hours.