CLASSES

Bowel Prep Combinations

DEA CLASS

Rx

DESCRIPTION

Bowel cleansing kit used in adults prior to colonoscopy; the HalfLytely and Bisacodyl Bowel Prep Kit contains PEG 3350 with electrolytes solution and bisacodyl tablets; PEG 3350 is an osmotic laxative that is not systemically absorbed, electrolytes are added to maintain water/electrolyte balance; bisacodyl is a stimulant laxative.

COMMON BRAND NAMES

GaviLyte-H, HalfLytely and Bisacodyl Tablet Bowel Prep Kit, PEG-Prep and Bisacodyl

HOW SUPPLIED

Bisacodyl;Polyethylene Glycol 3350, Potassium Chloride, Sodium Bicarbonate, Sodium Chloride/GaviLyte-H/HalfLytely and Bisacodyl Tablet Bowel Prep Kit/PEG-Prep and Bisacodyl Oral Pwd F/Recon
Bisacodyl;Polyethylene Glycol 3350, Potassium Chloride, Sodium Bicarbonate, Sodium Chloride/GaviLyte-H/HalfLytely and Bisacodyl Tablet Bowel Prep Kit/PEG-Prep and Bisacodyl Oral Tab DR

DOSAGE & INDICATIONS

MAXIMUM DOSAGE

2 liters/24 hours PO polyethylene glycol; electrolytes solution and 10 mg/24 hours PO delayed-release bisacodyl tablets.

2 liters/24 hours PO polyethylene glycol; electrolytes solution and 10 mg/24 hours PO delayed-release bisacodyl tablets.

Safety and efficacy have not been established.

Safety and efficacy have not been established.

DOSING CONSIDERATIONS

Specific guidelines for dosage adjustments in hepatic impairment are not available; it appears that no dosage adjustments are needed.

Specific guidelines for dosage adjustments in renal impairment are not available; it appears that no dosage adjustments are needed.

ADMINISTRATION

For storage information, see specific product information within the How Supplied section.

STORAGE

GaviLyte-H:
- Reconstituted product may be refrigerated (36 to 46 degrees F) for use within 48 hours
- Store between 68 to 77 degrees F, excursions permitted 59 to 86 degrees F
HalfLytely and Bisacodyl Tablet Bowel Prep Kit:
- Reconstituted product may be refrigerated (36 to 46 degrees F) for use within 48 hours
- Store between 68 to 77 degrees F, excursions permitted 59 to 86 degrees F
PEG-Prep and Bisacodyl:
- Reconstituted product may be refrigerated (36 to 46 degrees F) for use within 48 hours
- Store between 68 to 77 degrees F, excursions permitted 59 to 86 degrees F

CONTRAINDICATIONS / PRECAUTIONS

Polyethylene glycol; electrolytes; bisacodyl is contraindicated for use in those with known polyethylene glycol hypersensitivity or bisacodyl hypersensitivity or with hypersensitivity to any of the components of this specific commercial product. Hives and skin rashes have been reported with PEG-3350 based products that are suggestive of an allergic reaction.

Polyethylene glycol; electrolytes; bisacodyl is contraindicated for use in patients with known or suspected GI obstruction, GI perforation, toxic colitis, or toxic megacolon. Patients with symptoms suggestive of bowel obstruction (e.g., acute abdomen or symptoms of appendicitis, abdominal pain, distension, nausea, or vomiting) should be evaluated prior to initiating bowel evacuation. Use with caution in the presence of ileus, gastric retention, inflammatory bowel disease such as severe ulcerative colitis, or other conditions where there may be compromised integrity of the bowel wall as use of these products may lead to very rare instances of bowel perforation in such patients. If patients develop severe abdominal pain or rectal GI bleeding, patients should be evaluated as soon as possible. Due to the potential choking hazard, use polyethylene glycol; electrolytes solution with caution in those patients prone to aspiration or regurgitation (e.g., coma, gag reflex depression, dysphagia, esophageal stricture, semiconscious, or impaired mental status, like dementia). Do not combine polyethylene glycol; electrolytes solution with starch-based thickeners. When polyethylene glycol (PEG) is mixed with starch-thickened liquids, it reduces the viscosity of the starch-thickened liquid resulting in thinning of the liquid; cases of choking and potential aspiration were reported in patients with dysphagia.

A large volume of liquid must be ingested during preparation prior to polyethylene glycol;electrolytes; bisacodyl use, patients with fluid restrictions such as patients with renal disease (including renal impairment and renal failure) or patients taking diuretics should be closely monitored. Consider performing baseline and post-colonoscopy laboratory tests (sodium, potassium, calcium, creatinine, and BUN) in these patients.

There have been rare reports of generalized tonic-clonic seizures associated with use of polyethylene glycol colon preparation products in patients with no prior history of seizure disorder. The cases of seizures were associated with electrolyte abnormalities (e.g., hyponatremia, hypokalemia). The neurologic abnormalities resolved with correction of fluid and electrolyte abnormalities. Therefore, polyethylene glycol; electrolytes; bisacodyl should be used with caution in patients using concomitant medications that increase the risk of electrolyte abnormalities or in patients with known or suspected hyponatremia. Consider performing baseline and post-colonoscopy laboratory tests (sodium, potassium, calcium, creatinine, and BUN) in these patients. Also consider laboratory tests if patients develop severe vomiting and/or signs of dehydration, even if the patient is otherwise healthy.

Use caution when administering polyethylene glycol; electrolytes; bisacodyl bowel preparation in geriatric patients. Of the 222 patients who received polyethylene glycol; electrolytes; bisacodyl in clinical trials, 73 (33%) were 65 years of age or older, and 18 (8%) were 75 years of age or older. Although no overall differences in safety or effectiveness were observed in the elderly patients, greater sensitivity of some older individuals cannot be ruled out.

The safety and efficacy of polyethylene glycol; electrolytes; bisacodyl in children have not been established.

Polyethylene glycol; electrolytes; bisacodyl is classified in FDA pregnancy risk category C. Administer during pregnancy only if clearly needed. Animal reproduction studies have not been performed. While high-molecular weight polyethylene glycols are common food additives and are not significantly absorbed from the GI tract, it is not known whether this drug can cause fetal harm when given during pregnancy or if the drug can affect reproductive capacity. Nevertheless, evidence appears to favor PEG-electrolyte solutions as preferred agents over bowel preparations like sodium phosphate (which might have a higher association with fluid and electrolyte abnormalities) when complete bowel evacuation is necessary during pregnancy; kits with bisacodyl may be unnecessary for successful bowel evacuation and it may be preferred to choose products that contain PEG 3350 with electrolytes as the only preparation item.

According to the manufacturer, caution should be exercised when polyethylene glycol; electrolytes; bisacodyl are administered to a nursing woman. It is not known if polyethylene glycol; electrolytes; bisacodyl is distributed into human breast-milk. The safest bowel evacuants for use in lactating women are those that are not systemically absorbed. Polyethylene glycol 3350 (PEG 3350) is a common food additive and is not significantly absorbed from the GI tract. Only 0.2% of an oral dose would be absorbed systemically by the lactating mother and significant passage to the milk seems unlikely. Consensus documents indicate that PEG-containing bowel preparations represent a low risk when used during breast-feeding. In addition, clinical data show that neither the active moiety of bisacodyl (BHPM or bis-(p-hydroxyphenyl)-pyridyl-2-methane) nor its glucuronides are excreted into the milk of healthy lactating females. Thus, clinical risk to the infant is negligible; no special precautions exist for nursing infants. Consider the benefits of breast-feeding, the risk of potential infant drug exposure, and the risk of an untreated or inadequately treated condition. If a breast-feeding infant experiences an adverse effect related to a maternally ingested drug, healthcare providers are encouraged to report the adverse effect to the FDA.

ADVERSE REACTIONS

anaphylactoid reactions / Rapid / Incidence not known
GI perforation / Delayed / Incidence not known
asystole / Rapid / Incidence not known
GI bleeding / Delayed / Incidence not known
pulmonary edema / Early / Incidence not known
seizures / Delayed / Incidence not known

edema / Delayed / Incidence not known
fecal incontinence / Early / Incidence not known
dyspnea / Early / Incidence not known
colitis / Delayed / Incidence not known
dysphagia / Delayed / Incidence not known

abdominal pain / Early / 38.0-53.0
nausea / Early / 34.0-42.0
vomiting / Early / 7.0-10.0
urticaria / Rapid / Incidence not known
rhinorrhea / Early / Incidence not known
fecal urgency / Early / Incidence not known
flatulence / Early / Incidence not known
diarrhea / Early / Incidence not known
dizziness / Early / Incidence not known
syncope / Early / Incidence not known

DRUG INTERACTIONS

Acetaminophen; Hydrocodone: (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as bisacodyl, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events. (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as polyethylene glycol, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events.
Aluminum Hydroxide: (Minor) The concomitant use of bisacodyl tablets with antacids can cause the enteric coating of the bisacody tablet to dissolve prematurely, leading to possible gastric irritation or dyspepsia. Avoid antacids within 1 hour before or after the bisacodyl dosage.
Aluminum Hydroxide; Magnesium Carbonate: (Minor) The concomitant use of bisacodyl tablets with antacids can cause the enteric coating of the bisacody tablet to dissolve prematurely, leading to possible gastric irritation or dyspepsia. Avoid antacids within 1 hour before or after the bisacodyl dosage.
Aluminum Hydroxide; Magnesium Hydroxide: (Minor) The concomitant use of bisacodyl tablets with antacids can cause the enteric coating of the bisacody tablet to dissolve prematurely, leading to possible gastric irritation or dyspepsia. Avoid antacids within 1 hour before or after the bisacodyl dosage.
Aluminum Hydroxide; Magnesium Hydroxide; Simethicone: (Minor) The concomitant use of bisacodyl tablets with antacids can cause the enteric coating of the bisacody tablet to dissolve prematurely, leading to possible gastric irritation or dyspepsia. Avoid antacids within 1 hour before or after the bisacodyl dosage.
Aluminum Hydroxide; Magnesium Trisilicate: (Minor) The concomitant use of bisacodyl tablets with antacids can cause the enteric coating of the bisacody tablet to dissolve prematurely, leading to possible gastric irritation or dyspepsia. Avoid antacids within 1 hour before or after the bisacodyl dosage.
Antacids: (Minor) The concomitant use of bisacodyl tablets with antacids can cause the enteric coating of the bisacody tablet to dissolve prematurely, leading to possible gastric irritation or dyspepsia. Avoid antacids within 1 hour before or after the bisacodyl dosage.
Aspirin, ASA; Citric Acid; Sodium Bicarbonate: (Minor) The concomitant use of bisacodyl tablets with antacids can cause the enteric coating of the bisacody tablet to dissolve prematurely, leading to possible gastric irritation or dyspepsia. Avoid antacids within 1 hour before or after the bisacodyl dosage.
Atropine; Difenoxin: (Moderate) Diphenoxylate can decrease GI motility. Drugs used to treat constipation, such as laxatives, would counteract the effect of antidiarrheals. In general, it would be illogical to concurrently administer these drugs at the same time. If an antidiarrheal medication is needed, it would be wise to temporarily discontinue use of agents with laxative effects.
Bisacodyl: (Moderate) When polyethylene glycol is used as pre-procedure bowel preparation, avoid concomitant use of stimulant laxatives. Colonic mucosal aphthous ulcerations and ischemic colitis have been observed following use of osmotic laxatives for bowel preparation and concomitant use of stimulant laxatives may increase this risk.
Bumetanide: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy. (Moderate) Monitor renal function and serum electrolytes and ensure adequate hydration before and after concomitant loop diuretic and polyethylene glycol 3350 use. Concomitant use may increase the risk for fluid and electrolyte abnormalities and renal injury.
Calcium Carbonate: (Moderate) By increasing intragastric pH, calcium carbonate can affect the dissolution of oral bisacodyl tablets; administration should be separated by 1 hour.
Calcium Carbonate; Famotidine; Magnesium Hydroxide: (Moderate) By increasing intragastric pH, calcium carbonate can affect the dissolution of oral bisacodyl tablets; administration should be separated by 1 hour. (Minor) The concomitant use of bisacodyl tablets with H2-blockers can cause the enteric coating of the bisacody tablet to dissolve prematurely, leading to possible gastric irritation or dyspepsia. Avoid H2-blockers within 1 hour before or after the bisacodyl dosage.
Calcium Carbonate; Magnesium Hydroxide: (Moderate) By increasing intragastric pH, calcium carbonate can affect the dissolution of oral bisacodyl tablets; administration should be separated by 1 hour.
Calcium Carbonate; Magnesium Hydroxide; Simethicone: (Moderate) By increasing intragastric pH, calcium carbonate can affect the dissolution of oral bisacodyl tablets; administration should be separated by 1 hour.
Calcium Carbonate; Risedronate: (Moderate) By increasing intragastric pH, calcium carbonate can affect the dissolution of oral bisacodyl tablets; administration should be separated by 1 hour.
Calcium Carbonate; Simethicone: (Moderate) By increasing intragastric pH, calcium carbonate can affect the dissolution of oral bisacodyl tablets; administration should be separated by 1 hour.
Calcium Phosphate, Supersaturated: (Moderate) Sodium phosphate monobasic monohydrate; sodium phosphate dibasic anhydrous should not be combined with additional laxatives or purgatives when being used to evacuate the bowel prior to colonic radiologic examinations or surgery. (Moderate) Sodium phosphate monobasic monohydrate; sodium phosphate dibasic anhydrous should not be combined with additional laxatives or purgatives when being used to evacuate the bowel prior to colonic radiologic examinations or surgery. Use in patients using small doses of polyethylene glycol 3350 (e.g., Miralax) may be permissable, as long as the patient does not use their chronic laxative therapy on the day of the preparation. Watch for electrolyte and fluid abnormalities in all patients using bowel preparations.
Calcium; Vitamin D: (Moderate) By increasing intragastric pH, calcium carbonate can affect the dissolution of oral bisacodyl tablets; administration should be separated by 1 hour.
Casanthranol; Docusate Sodium: (Moderate) When polyethylene glycol is used as pre-procedure bowel preparation, avoid concomitant use of stimulant laxatives. Colonic mucosal aphthous ulcerations and ischemic colitis have been observed following use of osmotic laxatives for bowel preparation and concomitant use of stimulant laxatives may increase this risk.
Castor Oil: (Moderate) When polyethylene glycol is used as pre-procedure bowel preparation, avoid concomitant use of stimulant laxatives. Colonic mucosal aphthous ulcerations and ischemic colitis have been observed following use of osmotic laxatives for bowel preparation and concomitant use of stimulant laxatives may increase this risk.
Chlorpheniramine; Hydrocodone: (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as bisacodyl, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events. (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as polyethylene glycol, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events.
Cimetidine: (Minor) The concomitant use of bisacodyl tablets with H2-blockers can cause the enteric coating of the bisacody tablet to dissolve prematurely, leading to possible gastric irritation or dyspepsia. Avoid H2-blockers within 1 hour before or after the bisacodyl dosage.
Dichlorphenamide: (Moderate) Use dichlorphenamide and bisacodyl together with caution. Dichlorphenamide increases potassium excretion and can cause hypokalemia and should be used cautiously with other drugs that may cause hypokalemia including laxatives. Measure potassium concentrations at baseline and periodically during dichlorphenamide treatment. If hypokalemia occurs or persists, consider reducing the dichlorphenamide dose or discontinuing dichlorphenamide therapy. (Moderate) Use dichlorphenamide and polyethylene glycol; electrolytes together with caution. Dichlorphenamide increases potassium excretion and can cause hypokalemia and should be used cautiously with other drugs that may cause hypokalemia including laxatives. Measure potassium concentrations at baseline and periodically during dichlorphenamide treatment. If hypokalemia occurs or persists, consider reducing the dichlorphenamide dose or discontinuing dichlorphenamide therapy.
Diphenoxylate; Atropine: (Moderate) Diphenoxylate can decrease GI motility. Drugs used to treat constipation, such as laxatives, would counteract the effect of antidiarrheals. In general, it would be illogical to concurrently administer these drugs at the same time. If an antidiarrheal medication is needed, it would be wise to temporarily discontinue use of agents with laxative effects.
Docusate Sodium; Senna: (Moderate) When polyethylene glycol is used as pre-procedure bowel preparation, avoid concomitant use of stimulant laxatives. Colonic mucosal aphthous ulcerations and ischemic colitis have been observed following use of osmotic laxatives for bowel preparation and concomitant use of stimulant laxatives may increase this risk.
Ethacrynic Acid: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy. (Moderate) Monitor renal function and serum electrolytes and ensure adequate hydration before and after concomitant loop diuretic and polyethylene glycol 3350 use. Concomitant use may increase the risk for fluid and electrolyte abnormalities and renal injury.
Famotidine: (Minor) The concomitant use of bisacodyl tablets with H2-blockers can cause the enteric coating of the bisacody tablet to dissolve prematurely, leading to possible gastric irritation or dyspepsia. Avoid H2-blockers within 1 hour before or after the bisacodyl dosage.
Food: (Minor) The concomitant use of bisacodyl oral tablets with milk-containing products can cause the enteric coating of the bisacodyl tablets to dissolve prematurely, leading to possible gastric irritation or dyspepsia. When taking bisacodyl tablets, it is advisable to avoid ingesting milk products within 1 hour before or after the bisacodyl dosage.
Furosemide: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy. (Moderate) Monitor renal function and serum electrolytes and ensure adequate hydration before and after concomitant loop diuretic and polyethylene glycol 3350 use. Concomitant use may increase the risk for fluid and electrolyte abnormalities and renal injury.
Guaifenesin; Hydrocodone: (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as bisacodyl, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events. (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as polyethylene glycol, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events.
Guaifenesin; Hydrocodone; Pseudoephedrine: (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as bisacodyl, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events. (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as polyethylene glycol, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events.
H2-blockers: (Minor) The concomitant use of bisacodyl tablets with H2-blockers can cause the enteric coating of the bisacody tablet to dissolve prematurely, leading to possible gastric irritation or dyspepsia. Avoid H2-blockers within 1 hour before or after the bisacodyl dosage.
Homatropine; Hydrocodone: (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as bisacodyl, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events. (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as polyethylene glycol, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events.
Hydrocodone: (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as bisacodyl, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events. (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as polyethylene glycol, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events.
Hydrocodone; Ibuprofen: (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as bisacodyl, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events. (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as polyethylene glycol, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events.
Hydrocodone; Pseudoephedrine: (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as bisacodyl, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events. (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as polyethylene glycol, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events.
Ibuprofen; Famotidine: (Minor) The concomitant use of bisacodyl tablets with H2-blockers can cause the enteric coating of the bisacody tablet to dissolve prematurely, leading to possible gastric irritation or dyspepsia. Avoid H2-blockers within 1 hour before or after the bisacodyl dosage.
Lactulose: (Major) In general, other laxatives, such as bisacodyl, should not be used concurrently with lactulose, especially during the initial phase of therapy for portal-systemic encephalopathy, because the loose stools resulting from their use may falsely suggest that adequate lactulose dosage has been achieved. (Major) In general, other laxatives, such as polyethylene glycol 3350, should not be used concurrently with lactulose, especially during the initial phase of therapy for portal-systemic encephalopathy, because the loose stools resulting from their use may falsely suggest that adequate lactulose dosage has been achieved.
Loop diuretics: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy. (Moderate) Monitor renal function and serum electrolytes and ensure adequate hydration before and after concomitant loop diuretic and polyethylene glycol 3350 use. Concomitant use may increase the risk for fluid and electrolyte abnormalities and renal injury.
Magnesium Hydroxide: (Minor) The concomitant use of bisacodyl tablets with antacids can cause the enteric coating of the bisacody tablet to dissolve prematurely, leading to possible gastric irritation or dyspepsia. Avoid antacids within 1 hour before or after the bisacodyl dosage.
Magnesium Sulfate; Potassium Sulfate; Sodium Sulfate: (Major) Avoid use of stimulant laxatives, such as bisacodyl, with magnesium sulfate; potassium sulfate; sodium sulfate. Concurrent use may increase the risk of mucosal ulceration or ischemic colitis.
Nizatidine: (Minor) The concomitant use of bisacodyl tablets with H2-blockers can cause the enteric coating of the bisacody tablet to dissolve prematurely, leading to possible gastric irritation or dyspepsia. Avoid H2-blockers within 1 hour before or after the bisacodyl dosage.
Omeprazole; Sodium Bicarbonate: (Minor) The concomitant use of bisacodyl tablets with antacids can cause the enteric coating of the bisacody tablet to dissolve prematurely, leading to possible gastric irritation or dyspepsia. Avoid antacids within 1 hour before or after the bisacodyl dosage.
Pimozide: (Moderate) According to the manufacturer of pimozide, the drug should not be coadministered with drugs known to cause electrolyte imbalances, such as polyethylene glycol used in colon-cleansing regimens, except when indicated. Use in patients using small doses of polyethylene glycol 3350 (e.g., Miralax) may be permissable, as long as not excessive. Pimozide is associated with a well-established risk of QT prolongation and torsade de pointes (TdP), and electrolyte imbalances (e.g., hypokalemia, hypocalcemia, hypomagnesemia) may increase the risk of life-threatening arrhythmias. Pimozide is contraindicated in patients with known hypokalemia or hypomagnesemia.
Polyethylene Glycol; Electrolytes: (Major) Avoid use of stimulant laxatives, such as bisacodyl, with magnesium sulfate; potassium sulfate; sodium sulfate. Concurrent use may increase the risk of mucosal ulceration or ischemic colitis.
Polyethylene Glycol; Electrolytes; Ascorbic Acid: (Major) Avoid use of stimulant laxatives, such as bisacodyl, with magnesium sulfate; potassium sulfate; sodium sulfate. Concurrent use may increase the risk of mucosal ulceration or ischemic colitis.
Proton pump inhibitors: (Minor) The concomitant use of bisacodyl oral tablets with drugs that raise gastric pH like proton pump inhibitors can cause the enteric coating of the bisacodyl tablets to dissolve prematurely, leading to possible gastric irritation or dyspepsia. When taking bisacodyl tablets, it is advisable to avoid PPIs within 1 hour before or after the bisacodyl dosage.
Ranitidine: (Minor) The concomitant use of bisacodyl tablets with H2-blockers can cause the enteric coating of the bisacody tablet to dissolve prematurely, leading to possible gastric irritation or dyspepsia. Avoid H2-blockers within 1 hour before or after the bisacodyl dosage.
Senna: (Moderate) When polyethylene glycol is used as pre-procedure bowel preparation, avoid concomitant use of stimulant laxatives. Colonic mucosal aphthous ulcerations and ischemic colitis have been observed following use of osmotic laxatives for bowel preparation and concomitant use of stimulant laxatives may increase this risk.
Sodium Bicarbonate: (Minor) The concomitant use of bisacodyl tablets with antacids can cause the enteric coating of the bisacody tablet to dissolve prematurely, leading to possible gastric irritation or dyspepsia. Avoid antacids within 1 hour before or after the bisacodyl dosage.
Sodium Phosphate Monobasic Monohydrate; Sodium Phosphate Dibasic Anhydrous: (Moderate) Sodium phosphate monobasic monohydrate; sodium phosphate dibasic anhydrous should not be combined with additional laxatives or purgatives when being used to evacuate the bowel prior to colonic radiologic examinations or surgery. (Moderate) Sodium phosphate monobasic monohydrate; sodium phosphate dibasic anhydrous should not be combined with additional laxatives or purgatives when being used to evacuate the bowel prior to colonic radiologic examinations or surgery. Use in patients using small doses of polyethylene glycol 3350 (e.g., Miralax) may be permissable, as long as the patient does not use their chronic laxative therapy on the day of the preparation. Watch for electrolyte and fluid abnormalities in all patients using bowel preparations.
Stimulant Laxatives: (Moderate) When polyethylene glycol is used as pre-procedure bowel preparation, avoid concomitant use of stimulant laxatives. Colonic mucosal aphthous ulcerations and ischemic colitis have been observed following use of osmotic laxatives for bowel preparation and concomitant use of stimulant laxatives may increase this risk.
Torsemide: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy. (Moderate) Monitor renal function and serum electrolytes and ensure adequate hydration before and after concomitant loop diuretic and polyethylene glycol 3350 use. Concomitant use may increase the risk for fluid and electrolyte abnormalities and renal injury.

PREGNANCY AND LACTATION

Polyethylene glycol; electrolytes; bisacodyl is classified in FDA pregnancy risk category C. Administer during pregnancy only if clearly needed. Animal reproduction studies have not been performed. While high-molecular weight polyethylene glycols are common food additives and are not significantly absorbed from the GI tract, it is not known whether this drug can cause fetal harm when given during pregnancy or if the drug can affect reproductive capacity. Nevertheless, evidence appears to favor PEG-electrolyte solutions as preferred agents over bowel preparations like sodium phosphate (which might have a higher association with fluid and electrolyte abnormalities) when complete bowel evacuation is necessary during pregnancy; kits with bisacodyl may be unnecessary for successful bowel evacuation and it may be preferred to choose products that contain PEG 3350 with electrolytes as the only preparation item.

According to the manufacturer, caution should be exercised when polyethylene glycol; electrolytes; bisacodyl are administered to a nursing woman. It is not known if polyethylene glycol; electrolytes; bisacodyl is distributed into human breast-milk. The safest bowel evacuants for use in lactating women are those that are not systemically absorbed. Polyethylene glycol 3350 (PEG 3350) is a common food additive and is not significantly absorbed from the GI tract. Only 0.2% of an oral dose would be absorbed systemically by the lactating mother and significant passage to the milk seems unlikely. Consensus documents indicate that PEG-containing bowel preparations represent a low risk when used during breast-feeding. In addition, clinical data show that neither the active moiety of bisacodyl (BHPM or bis-(p-hydroxyphenyl)-pyridyl-2-methane) nor its glucuronides are excreted into the milk of healthy lactating females. Thus, clinical risk to the infant is negligible; no special precautions exist for nursing infants. Consider the benefits of breast-feeding, the risk of potential infant drug exposure, and the risk of an untreated or inadequately treated condition. If a breast-feeding infant experiences an adverse effect related to a maternally ingested drug, healthcare providers are encouraged to report the adverse effect to the FDA.

MECHANISM OF ACTION

Mechanism of Action:
•PEG-3350: Polyethylene glycol; electrolytes solution contains polyethylene glycol 3350 (PEG 3350), an osmotic agent that binds water and causes water to be retained within the stool. The lack of intestinal enzymatic degradation or bacterial metabolism of PEG 3350 contributes to the drug's effectiveness. PEG 3350 softens stool consistency, increases stool frequency, and facilitates stool evacuation. PEG 3350 does not affect colonic transit time. A balance of electrolytes (e.g., sodium, chloride, potassium and bicarbonate) are added to the solution to counteract losses resulting from bowel evacuation. The concentration of electrolytes in the polyethylene glycol; electrolytes solution causes no net absorption or secretion of electrolytes; thus water and electrolyte balance are usually maintained even after administration of large volumes.
 
•Bisacodyl: Bisacodyl, a stimulant laxative, is hydrolyzed by intestinal brush border enzymes and colonic bacteria to form an active metabolite [bis-(p-hydroxyphenyl) pyridyl-2 methane; (BHPM)] that acts directly on the colonic mucosa to produce colonic peristalsis.

PHARMACOKINETICS

•PEG-3350: Polyethylene glycol; electrolytes solution is administered orally as a solution in water. Roughly 0.2% of a dose has been absorbed systemically in some studies of PEG 3350, systemically absorbed amount is quickly excreted in the urine. 
 
•Bisacodyl: Bisacodyl is administered orally. Bisacodyl distributes locally, and the circulating drug undergoes hepatic metabolism and is then excreted in the urine.