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Electrolyte/Discontinued

PEG-3350, SODIUM CHLORIDE, SODIUM BICARBONATE, POTASSIUM CHLORIDE AND BISACODYL

PEG-3350, SODIUM CHLORIDE, SODIUM BICARBONATE, POTASSIUM CHLORIDE AND BISACODYL

Clinical safety rating

safe

No significant drug interactions Can cause hypernatremia and fluid overload.


Mechanism of Action

Combination of osmotic laxative (PEG-3350, sodium chloride, sodium bicarbonate, potassium chloride) and stimulant laxative (bisacodyl). PEG-3350 causes water retention in colon, increasing stool water content and volume, stimulating peristalsis. Electrolytes maintain fluid/electrolyte balance. Bisacodyl stimulates colonic smooth muscle contraction and inhibits water absorption.

What the body does with it

MetabolismPEG-3350 is not metabolized; excreted unchanged in feces. Bisacodyl is metabolized in the liver and small intestine to its active metabolite, bis-(p-hydroxyphenyl)-pyridyl-2-methane, by ester hydrolysis. Electrolytes are absorbed or secreted by normal physiological mechanisms.
ExcretionPEG-3350 is not absorbed, excreted unchanged in feces. Electrolytes (sodium chloride, sodium bicarbonate, potassium chloride) are absorbed and renally excreted; bisacodyl is primarily excreted as glucuronide conjugates in feces (biliary) and urine (renal). Approximately 95% of bisacodyl is recovered in feces, 5% in urine.
Half-lifePEG-3350: not applicable (non-absorbed). Bisacodyl: terminal half-life 8–16 hours; clinical effect peaks within 6–12 hours.
Protein bindingPEG-3350: negligible (non-absorbed). Bisacodyl: ~90% bound to plasma proteins.
Volume of DistributionPEG-3350: not distributed (non-absorbed). Bisacodyl: Vd approximately 0.4–0.6 L/kg, indicating moderate tissue distribution.
BioavailabilityPEG-3350: negligible systemic absorption (<0.2%). Bisacodyl: oral bioavailability 15–30% due to first-pass metabolism; rectal bioavailability ~50%.
Onset of ActionPEG-3350 with electrolytes: 1–2 hours (oral). Bisacodyl: 6–12 hours (oral tablet), 0.25–1 hour (rectal suppository).
Duration of ActionPEG-3350 with electrolytes: bowel cleansing effect lasts until evacuation is complete (typically 2–4 hours); bisacodyl: cathartic effect may last up to 6 hours; clinical bowel preparation effects resolve within 24 hours.
Molecular WeightPEG-3350: ~3500 Da (range 3010-3680); Sodium Chloride: 58.44; Sodium Bicarbonate: 84.01; Potassium Chloride: 74.55; Bisacodyl: 361.39

Classification & Brands

Dosing & administration

For colonoscopy preparation: Day 1: 4 bisacodyl tablets (5 mg each) orally at 2000. Day 2: 1 liter of PEG-3350 plus electrolytes solution (4 sachets dissolved in 4 liters water) orally at 0800; then 2 liters more over 3-4 hours. Alternatively, split-dose regimen: 2 liters evening before colonoscopy and 2 liters morning of procedure.

Dosage formFOR SOLUTION, TABLET, DELAYED RELEASE
Renal impairmentContraindicated in severe renal impairment (CrCl <30 mL/min) due to risk of electrolyte disturbances. In moderate impairment (CrCl 30-50 mL/min): use with caution, monitor electrolytes. No dose adjustment specified by manufacturer for mild impairment.
Liver impairmentNo specific dose adjustment required for hepatic impairment based on Child-Pugh class. However, use with caution in severe hepatic impairment due to potential for encephalopathy from electrolyte shifts.
Pediatric useNot FDA-approved for children <2 years. For children 2-11 years: PEG-3350 plus electrolytes 75-100 mL/kg/dose orally, up to 4 L, for colonoscopy preparation. Bisacodyl tablets: children 6-11 years: 2.5-5 mg orally at bedtime day before procedure. Weight-based: not standardized; refer to specific pediatric protocols.
Geriatric useUse with caution due to increased risk of electrolyte imbalance and dehydration. No specific dose reduction recommended; however, consider lower volume (2 L) split-dose regimen. Monitor renal function and electrolytes before and after procedure.

Use during pregnancy

1st trimesterBisacodyl and PEG-3350 with electrolytes are generally avoided in the first trimester unless clearly necessary. Stimulant laxatives like bisacodyl may theoretically increase uterine irritability; osmotic laxatives are preferred.
2nd trimesterMay be used with caution during the second trimester for short-term treatment of constipation when dietary measures fail. Minimal systemic absorption of PEG-3350 and bisacodyl is expected.
3rd trimesterUse with caution in the third trimester; avoid prolonged use. Risk of electrolyte disturbances in mother and fetus; bisacodyl may rarely cause uterine contractions.

Clinical note

No significant drug interactions Can cause hypernatremia and fluid overload.

FDA categoryAnimal
Placental transferMinimal placental transfer expected for PEG-3350 due to high molecular weight (average range ~3500 Da); bisacodyl is poorly absorbed and its active metabolite (BHPM) has low systemic exposure, limiting placental crossing.
BreastfeedingPEG-3350 and electrolytes are minimally absorbed and considered compatible with breastfeeding. Bisacodyl is also poorly absorbed; however, its active metabolite may be excreted in milk in small amounts. Monitor infant for diarrhea or abdominal discomfort.
Lactation RatingL2: Limited data - probably compatible (safest options: PEG-3350 alone or with electrolytes; bisacodyl used occasionally and at low doses is considered acceptable).
Teratogenic RiskFirst trimester: Minimal systemic absorption; no known teratogenic effects. Second/third trimester: Avoid use due to risk of electrolyte imbalance and fluid shifts; not associated with congenital anomalies.
Fetal MonitoringMonitor serum electrolytes, renal function, and fluid status. Assess for hypotension, tachycardia, and signs of dehydration. Fetal monitoring if maternal electrolyte disturbances occur.
Fertility EffectsNo known adverse effects on fertility from components. Osmotic laxatives and stimulant laxatives have no established impact on reproductive function.

Warnings & precautions

■ FDA Black Box Warning

WARNING: SERIOUS FLUID AND ELECTROLYTE ABNORMALITIES. There have been reports of significant fluid shifts, severe electrolyte abnormalities (including hypokalemia, hyponatremia), and dehydration in patients treated with this product. The risk is increased in patients with renal insufficiency, electrolyte abnormalities, or those taking concomitant medications that affect electrolytes. Monitor and correct fluid and electrolyte disturbances before use.

Side Effect Profile

Common Effectsfluid replacement
Serious Effects

Absolute Contraindications

Gastrointestinal obstructionAcute surgical abdomen (e.g., appendicitis, peritonitis)Ileus or intestinal perforationSevere inflammatory bowel disease (e.g., toxic colitis)Hypersensitivity to any componentSevere dehydration or electrolyte disturbances (before correction)

Clinical Precautions

PrecautionsRisk of electrolyte abnormalities and dehydration; correct before use, Use with caution in patients with renal impairment, electrolyte disturbances, or taking diuretics, ACE inhibitors, or NSAIDs, Risk of serious arrhythmias due to electrolyte imbalance, Possible colonic mucosal ulcerations (aphthoid ulcers) with bisacodyl, Gag reflex may be impaired in elderly, debilitated, or patients with swallowing disorders; risk of aspiration, May cause Mallory-Weiss tear or esophageal perforation if vomiting occurs, Monitor for QT prolongation in at-risk patients
Food/DietaryAvoid solid foods, dairy, and red/purple colored liquids during preparation. Only clear liquids (water, clear broth, apple juice, gelatin, tea or coffee without cream) are permitted until after the procedure.

Clinical Tips & Counseling

Clinical PearlsThis combination is used for colonoscopy preparation. Ensure adequate hydration and renal function assessment; avoid in patients with ileus, GI obstruction, or significant electrolyte abnormalities. Bisacodyl is a stimulant laxative that may cause cramping. Administer in divided doses as per protocol.
Patient AdviceDrink plenty of clear liquids to stay hydrated. · Follow the exact dosing schedule provided by your doctor. · Expect frequent, watery bowel movements; stay near a restroom. · Do not eat solid foods during the preparation; only clear liquids. · Notify your doctor if you experience severe abdominal pain, vomiting, or signs of dehydration.

PEG-3350, SODIUM CHLORIDE, SODIUM BICARBONATE, POTASSIUM CHLORIDE AND BISACODYL Interactions

Loading safety data…

This overview is compiled from peer-reviewed clinical sources and FDA labeling. It's here to support — not replace — clinical judgment. Always verify dosing against your institution's current protocols before prescribing.

On this page

Mechanism of ActionDosing & administrationUse during pregnancyWarnings & precautionsDrug interactions

Compare with

ACETATED RINGER'S IN PLASTIC CONTAINERACYCLOVIR IN SODIUM CHLORIDE 0.9% PRESERVATIVE FREEAMIKACIN SULFATE IN SODIUM CHLORIDE 0.9% IN PLASTIC CONTAINERAMIKIN IN SODIUM CHLORIDE 0.9% IN PLASTIC CONTAINERAMINOPHYLLINE IN SODIUM CHLORIDE 0.45%

External sources

DailyMed (NIH) PubMed OpenFDA