First-lineMovicol / Laxido

Macrogol (PEG)

Osmotic polyethylene glycol laxative

Alternative osmotic laxative — better tolerated than lactulose.

Oral (sachet in 125 mL water)

First-line for

  • Pregnancy constipation intolerant to lactulose
  • Faecal impaction

Mechanism

Non-absorbed PEG binds water molecules → increased stool water content and volume without electrolyte flux.

"Movicol moves stool with minimal wind"

  • Less flatulence than lactulose
  • One sachet in 125 mL water
  • Impaction: up to 8 sachets/day for 3 days

Dosing

Chronic constipation
1–3 sachets/day
Impaction
8 sachets/day × up to 3 days

Contraindications

  • AbsoluteIntestinal obstruction/perforation
  • AbsoluteToxic megacolon

Side effects

  • Bloating, cramps
  • Nausea
  • Electrolyte disturbance with high-dose disimpaction

Fetal & maternal notes

  • Not absorbed — safe throughout pregnancy and lactation

Key interactions

  • Other oral drugs

    Caution

    May ↓ absorption during disimpaction dosing

Clinical pearls

  • 💡 Preferred over stimulants in pregnancy
  • 💡 Adequate hydration is essential

Content last reviewed: REPLACE_ME (e.g. 2026-07)

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For educational use only

Not medical advice. Verify dosing against the BNF and your local trust guidelines before prescribing.