1. Clinical & Scientific Overview
Polyethylene Glycol (PEG 3350 / Macrogol) (TIP-MED-000078, Reference Code [5.10]) is classified under
Gastrointestinal & Hepatobiliary Medicines (Ch 05) as a Iso-Osmotic Laxative (Inert Non-Absorbable Water-Binding Polymer).
Within the Indian regulatory and compendial framework, it is governed under Schedule H Prescription Drug (To be sold by retail on the prescription of a Registered Medical Practitioner only — Drugs Rules 1945).
Representative Indian Market Examples (Edition 2.7 Ch 05 [5.10], p. 64): Pegmove (Raptakos), Peglec (Tablet India—electrolyte bowel prep), Cremalax-PEG, Muout (Dr. Reddy's), Pegred, Forlax — Strengths & Dosage Forms: Oral Powder for Solution: 17 g/dose (in measuring cap bottle or sachets, plain PEG 3350 or PEG 3350 + Electrolytes: Macrogol 13.125 g/sachet); Oral Liquid Concentrate; High-Volume Colonoscopy Bowel Prep Sachets (137.15 g for 2 Litres)
Oral Powder for Solution: 17 g/dose (in measuring cap bottle or sachets, plain PEG 3350 or PEG 3350 + Electrolytes: Macrogol 13.125 g/sachet); Oral Liquid Concentrate; High-Volume Colonoscopy Bowel Prep Sachets (137.15 g for 2 Litres)
3. Mechanism of Action & Pharmacodynamics
Iso-Osmotic Laxative (Inert Non-Absorbable Water-Binding Polymer) acting on target receptor/enzyme pathways in Gastrointestinal & Hepatobiliary Medicines (Ch 05): clinical efficacy is mediated via Iso-Osmotic Laxative (Inert Non-Absorbable Water-Binding Polymer) for Chronic idiopathic constipation and faecal impaction (first-line osmotic laxative in elderly and IBS-C, causing minimal gas/bloating because it is not fermented by colonic bacteria); bowel cleansing prior to colonoscopy (high-volume PEG + electrolytes)..
4. Therapeutic Indications & Evidence-Supported Uses
- Chronic idiopathic constipation and faecal impaction (first-line osmotic laxative in elderly and IBS-C, causing minimal gas/bloating because it is not fermented by colonic bacteria)
- bowel cleansing prior to colonoscopy (high-volume PEG + electrolytes)
🇮🇳 Jurisdiction & Indication Note: Indications and schedules reflect Indian compendial and regulatory records (CDSCO / Indian Pharmacopoeia & NFI / NLEM 2022). Where international reference labels (US FDA DailyMed / NCBI StatPearls) are cited for pharmacokinetic or mechanistic parameters, international approvals do not automatically imply CDSCO approval in India.
5. Educational Dosage Context, Formulations & Administration
Educational Dosing & Regimen Summary: General Adult Reference: Chronic Constipation: 17 g (1 standard measuring capful or 1–2 sachets) dissolved in 120–240 mL (1 glass) of water once daily (up to twice daily if needed; onset in 24 to 72 hours). Faecal Impaction: Up to 8 sachets dissolved in 1 litre of water consumed over 6 hours for 1–3 days. Follow physician prescription.
Administration & Meal Timing: With or without food, dissolved completely in water, juice, or beverage. | Once daily in the morning or evening.
6. Pharmacokinetics, Metabolism & Renal/Hepatic Adjustment
Absorption, distribution, metabolism, and excretion follow class pharmacokinetic profile; verify patient renal/hepatic function.
Renal & Hepatic: Virtually zero systemic absorption (<0.2%) and no colonic fermentation; plain PEG 3350 (or balanced iso-osmotic PEG+electrolytes) is exceptionally safe in CKD and hepatic disease (though Lactulose remains preferred specifically when ammonia trapping for hepatic encephalopathy is the primary goal).
Renal & Hepatic: Virtually zero systemic absorption (<0.2%) and no colonic fermentation; plain PEG 3350 (or balanced iso-osmotic PEG+electrolytes) is exceptionally safe in CKD and hepatic disease (though Lactulose remains preferred specifically when ammonia trapping for hepatic encephalopathy is the primary goal).
Renal & Hepatic: Virtually zero systemic absorption (<0.2%) and no colonic fermentation; plain PEG 3350 (or balanced iso-osmotic PEG+electrolytes) is exceptionally safe in CKD and hepatic disease (though Lactulose remains preferred specifically when ammonia trapping for hepatic encephalopathy is the primary goal).
7. Contraindications, Precautions & High-Risk Warnings
- Contraindicated in bowel obstruction, gastrointestinal perforation, toxic megacolon, and paralytic ileus. In patients with dysphagia or impaired gag reflex, thickeners modifying liquid viscosity may interact with PEG (risk of aspiration if starch-based thickeners are liquefied by PEG).
Key Clinical Precautions: Renal & Hepatic: Virtually zero systemic absorption (<0.2%) and no colonic fermentation; plain PEG 3350 (or balanced iso-osmotic PEG+electrolytes) is exceptionally safe in CKD and hepatic disease (though Lactulose remains preferred specifically when ammonia trapping for hepatic encephalopathy is the primary goal).
8. Adverse Effects Profile
- Mild abdominal distension, soft/loose stools, mild nausea (far less flatulence and bloating than lactulose because colonic bacteria do not ferment PEG into gas).
- Electrolyte imbalance (hyponatraemia/hypokalaemia) or dehydration if over-dosed causing profuse watery diarrhoea; rare allergic urticaria.
- Monitor for severe hypersensitivity, organ toxicity, or dose-limiting adverse events.
9. Major Drug–Drug, Drug–Food & Drug–Herb Interactions
- May transiently reduce the intestinal absorption of other oral medications taken simultaneously due to accelerated intestinal transit and intraluminal fluid volume—administer other chronic oral medications at least 1 hour before or 1 hour after taking PEG
10. Clinical Monitoring, Patient Counselling & Storage
Clinical & Laboratory Monitoring: Monitor clinical response, baseline renal/hepatic parameters, and relevant serum biomarkers.
Pharmacist Patient Counselling Points:
- Patient Counselling Checklist: Stir the powder into a full glass of water until completely clear and drink immediately. Explain that unlike lactulose, PEG does not cause sweet nausea or excessive intestinal gas, and does not affect blood sugar in diabetics. Allow 1 to 3 days for comfortable bowel movement.
- Meal & Clock Timing Instruction: With or without food, dissolved completely in water, juice, or beverage. (Once daily in the morning or evening.)
- Missed Dose Protocol: Take as soon as remembered on the same day; do not double.
- Geriatric Dispensing Pearl: First-line guideline-recommended laxative for chronic constipation in elderly patients due to its iso-osmotic mechanism, absence of colonic fermentation/gas, and safety in diabetics and renal patients.
Storage, Stability & Dispensing Safeguards: Store below 25°C–30°C in original moisture- and light-resistant packaging out of reach of children. Available forms: Oral Powder for Solution: 17 g/dose (in measuring cap bottle or sachets, plain PEG 3350 or PEG 3350 + Electrolytes: Macrogol 13.125 g/sachet); Oral Liquid Concentrate; High-Volume Colonoscopy Bowel Prep Sachets (137.15 g for 2 Litres)
11. Visual Pharmacology & Mechanism Diagram (svg-v339-01-adme-12-step-journey)
12. Authoritative References, Regulatory Sources & Editorial Disclaimer
Primary Compendial & Guideline Reference: Indian Pharmacist Desk Reference — Professional Edition 2.7 (2026–27) • Ch 05 [5.10] (p. 64)
Official Verification Portals: Indian Pharmacopoeia Commission (IPC) & National Formulary of India (NFI) • Central Drugs Standard Control Organization (CDSCO) • Ministry of Health & Family Welfare — NLEM 2022 • NCBI Bookshelf / StatPearls Pharmacology Reference • DailyMed (US FDA Official Prescribing Reference)
Last Medically & Pharmaceutically Reviewed: 2026-11-10 • Verification Status: HANDBOOK_SOURCE_CONTENT
Educational & Clinical Disclaimer: This reference profile is published solely for pharmacy education, academic study, and professional clinical reference. It does not substitute for patient-specific clinical judgement, qualified specialist oncology/medical supervision, or official CDSCO/IP prescribing information. Never self-medicate with prescription, Schedule H/H1/X, NDPS, or oncology medicines.
13. Related Reference Monographs, Educational Guides & Visual Concept
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