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Misoprostol (Cytotec)

Cytotec

Synthetic prostaglandin E1 analog (uterotonic + cytoprotective)

Synthetic PGE1 analog. Binds prostaglandin E receptors on uterine smooth muscle → contraction. Also: cytoprotective gastric mucosa (original indication for NSAID-induced ulcers); cervical ripening; GI motility.

Indications

  • Postpartum hemorrhage from uterine atony — used when carboprost contraindicated (asthma)
  • Cervical ripening + labor induction (low-dose 25-50 mcg)
  • Medical abortion (combined with mifepristone)
  • NSAID-induced ulcer prophylaxis (original indication, rarely used now with PPIs)

Dosing

ContextAdultPediatric
Postpartum hemorrhage800-1000 mcg per rectum (PR) — fast absorption + sustained effect; 600 mcg sublingual is alternative
Cervical ripening (term)25-50 mcg PV q3-6 h; off-label use
Medical abortion (with mifepristone)800 mcg PV at 24-48 h after mifepristone

Pharmacokinetics

Onset PR 10-20 min. Duration ~4 h. Hepatic metabolism + biliary excretion.

Hemodynamic effects

Generally hemodynamically neutral. Less ↑BP than methylergonovine; no bronchospasm like carboprost.

Side effects

  • !Diarrhea (most common)
  • !Fever + chills
  • !Nausea + vomiting
  • !Hyperthermia (high dose; can mimic MH temperature rise — context distinguishes)
  • !Uterine rupture (rare — high-dose with prior uterine surgery)

Contraindications

  • ×Pregnancy (Category X — except for OB indications above)
  • ×Hypersensitivity

Clinical pearls

  • PPH stepwise alternative: when CARBOPROST is contraindicated (ASTHMA), use MISOPROSTOL 800-1000 mcg PR.
  • PR route preferred for PPH — fastest + most reliable absorption when patient has uterus full of blood (oral absorption variable).
  • Hyperthermia 38-40°C is COMMON within 30 min of high-dose PR — distinguish from MH (no hypercarbia, no rigidity, normal CK).
  • CHEAP + WIDELY AVAILABLE globally — backbone of PPH management in resource-limited settings.
  • Cervical ripening: 25 mcg PV is ENOUGH — higher doses → uterine hyperstimulation + fetal compromise.
Education only — confirm against current package inserts and institutional protocols. Doses assume normal organ function unless otherwise noted.