It is a synthetic analog of natural prostaglandin E1. It produces a dose-related inhibition of gastric acid and pepsin secretion, and enhances mucosal resistance to injury. It is an effective anti-ulcer agent and also has oxytocic properties.



Generic Name:                               Misoprostol

Therapeutic Category:                Endocrine-Metabolic Agent

Pharmacologic Class:                  Prostaglandin

Composition:                                  Each uncoated tablet contains Misoprostol 200 mcg

Pregnancy Category:                   X

Presentation:                                  Available in the pack size as 4 tablets X 1 blister

Mechanism of Action

At the end of a pregnancy: There are many receptors and a small dose of misoprostol leads to strong contractions. Special attention is required in women with a live fetus [who may hyperstimulate (uterine)*]. Not for use by women with previous caesarean sections - it may cause a ruptured uterus. Uterine ruptures have also been reported occasionally in unscarred uterus.

In early pregnancy: There are few receptors and large doses of misoprostol may need to be given repeatedly in order to have an effect.

For termination of pregnancy: The sensitivity of the uterus to prostaglandins can be increased by giving the progesterone blocker mifepristone to the women 24-48 hours before treatment with misoprostol. This is especially useful in early pregnancy, although it also works in late pregnancy.


  •     Softens and opens (dilates) the cervix.
  •     Causes uterine contraction
  •     Starts (induces) labor.
  •     To prevent postpartum hemorrhage.
  •     In combination with mifepristone it cause abortion


Route of administration: Vaginally, orally, sub-lingual

400 μg or 800 μg

Smaller dose while given vaginally.


Absorption: Rapid absorption

Protein binding: Approximately 85%

Metabolism: Hepatic

Route of elimination: Urine

Half-life: 20-40 minutes


Adverse Effects

Most common side effect is Diarrhea followed by abdominal pain, nausea, flatulence, headache, dyspepsia, vomiting, and constipation.


MISTOL is contraindicated in the following populations and situations:

  •     Should not be taken by pregnant women for gastric ulcers
  •     Women with previous cesarean section


  •     Less force needed for dilatation,
  •     makes the intervention safer and easier
  •     shortens the time for the procedure
  •     reduces blood loss in the case of a subsequent surgical abortion


Uterine hyperstimulation: This may result in fetal heart rate abnormalities, uterine rupture, or placental abruption.