dromlakhani Movicol® (Macrogol 3350) — Prescribing Guide
Formulation: Each sachet (13.8 g powder) dissolved in 125 ml water Class: Osmotic laxative (macrogol 3350 + balanced electrolytes) Electrolytes per sachet: Na 65 mmol/L · K 5.4 mmol/L · Cl 53 mmol/L · HCO₃ 17 mmol/L
STEP 1 — Identify the Indication
| Indication | Definition |
|---|---|
| Chronic constipation | Infrequent or difficult bowel movements; ongoing need |
| Faecal impaction | Refractory constipation with faecal loading of rectum/colon — confirm by physical or radiological examination |
STEP 2 — Check Contraindications First
Do NOT use Movicol if:
- Intestinal perforation or obstruction (structural or functional)
- Ileus
- Severe inflammatory bowel disease: active Crohn's disease, ulcerative colitis, toxic megacolon
- Hypersensitivity to macrogol 3350 or any excipient
STEP 3 — Dose by Indication and Patient
🟦 Chronic Constipation
| Population | Dose | Duration |
|---|---|---|
| Adults, adolescents, elderly | 1–3 sachets daily in divided doses | Max 2 weeks per course; can repeat |
| Extended use (MS, Parkinson's, opioid/antimuscarinic-induced) | Adjust down to 1–2 sachets daily | Extended use permitted in these groups |
| Children <12 years | ❌ Not recommended — use Movicol Paediatric products | — |
Clinical studies show many patients respond to 1–2 sachets/day; dose typically reduces over time as stool consistency normalises.
🟥 Faecal Impaction
| Population | Dose | Duration |
|---|---|---|
| Adults, adolescents, elderly | 8 sachets daily, all consumed within a 6-hour period | Max 3 days |
| Impaired cardiovascular function | Max 2 sachets per hour (divide the 8 sachets over the day) | Max 3 days |
| Renal insufficiency | No dose adjustment needed | — |
| Children <12 years | ❌ Not recommended — use Movicol Paediatric products | — |
Preparation tip: For faecal impaction, all 8 sachets may be dissolved together in 1 litre of water.
STEP 4 — Administration Instructions
- Standard: Dissolve each sachet in 125 ml water
- Faecal impaction: Dissolve 8 sachets in 1 litre water
- Reconstituted solution must be used within 6 hours (store at 2–8°C if not used immediately)
- Sachets: store below 25°C
STEP 5 — Special Populations
| Population | Guidance |
|---|---|
| Renal insufficiency | No dose adjustment needed for either indication |
| Cardiovascular disease | For faecal impaction: max 2 sachets/hour (fluid load concern) |
| Pregnancy | Limited human data; animal studies show reproductive toxicity — use with caution, weigh risk/benefit |
| Breastfeeding | Safe — systemic absorption of macrogol 3350 is negligible |
| Driving / machinery | No effect |
STEP 6 — Warnings to Monitor
| Warning | Action |
|---|---|
| Fluid/electrolyte shifts (oedema, dyspnoea, fatigue, cardiac failure) | Stop immediately + check electrolytes |
| Diarrhoea | Reduce dose — usually resolves |
| Hyperkalaemia or hypokalaemia | Electrolyte monitoring if prolonged use or high-dose |
Drug Interactions
- Macrogol raises solubility of alcohol-soluble, water-insoluble drugs → altered absorption possible
- Transit rate increase may transiently reduce absorption of co-administered drugs
- Anti-epileptics: isolated reports of reduced efficacy — monitor levels
- General rule: space other oral medications away from Movicol doses where possible
Overdose
- Severe pain or distension → nasogastric aspiration
- Extensive fluid/electrolyte loss → correct electrolyte disturbances
Key Adverse Effects
| System | Effect |
|---|---|
| GI (most common) | Abdominal pain, diarrhoea, nausea, vomiting, bloating, flatulence, anal discomfort |
| Electrolytes | Hyperkalaemia, hypokalaemia |
| Immune | Allergic reactions (rare): anaphylaxis, angioedema, rash, urticaria |
| General | Peripheral oedema, headache |
Mild diarrhoea usually responds to dose reduction.
Clinical Guardrails
- Always confirm faecal impaction by physical or radiological exam before using the high-dose regimen
- Cardiovascular patients on impaction dose: must limit to 2 sachets/hour — rapid fluid load risk
- Do not use in IBD flares or obstruction — can cause perforation
- Extended use is acceptable for opioid/antimuscarinic-induced constipation and neurological disease (MS, Parkinson's) — adjust dose to minimum effective
- Pregnancy: caution warranted despite minimal absorption — animal reproductive toxicity data exist
Source: Movicol® 13.8 g Sachet — Summary of Product Characteristics (SPC). Norgine Limited, UK. Last revised 05/05/2011. PL 00322/0070.