Page Contents
WHAT IS IT?
Misoprostol is a prostaglandin E1 (PGE1) analog.
WHAT DOES IT DO?
Misoprostol is a medication that is used for a variety of contexts. In order to avoid confusion, here is break down of its mechanism of action (relative to the clinical usage of this medication).
Gastrointestinal usage: prostaglandins are important for protection of the gastric mucosa. Misoprostol does the following by binding to PG receptors on parietal cells:
- Increases production of the gastric mucous barrier
- Increases bicarbonate secretion
- Increases gastrin production
- Decreases acid secretion in the stomach
Cervical ripening/labor induction: this medication will cause the uterus to contract, and also causes effacement of the cervix. Its ability to cause uterine contractions also makes it useful to use this medication to prevent postpartum hemorrhage in the setting of uterine atony.
Termination of pregnancy: misoprostol is used either alone or in combination with other agents (either methotrexate or mifepristone) to cause medical abortion.
Maintenance of PDA: given that prostaglandin signaling is responsible for keeping this structure open, continued usage of misoprostol after birth can maintain the PDA.
WHEN DO WE USE IT?
Prevention of NSAID induced peptic ulcers, maintenance of a PDA (in patients with congenital heart abnormalities), cervical ripening/induction of labor (off label use), abortion, prevention of postpartum hemorrhage (in setting of uterine atony).
WHEN DO WE AVOID USING IT?
Women of childbearing potential/pregnant women (this medication will cause abortions)
HOW IS IT ADMINISTERED?
Generally administered orally, in the past it has been administered vaginally.
WHAT ARE THE SIDE EFFECTS/TOXICITY?
Diarrhea, termination of pregnancy
ANYTHING ELSE TO KEEP IN MIND?
Methotrexate can be used with misoprostol to cause medical abortions.
Mifepristone (RU-486) can be used with misoprostol to terminate pregnancies.
FURTHER READING
Page Updated: 05.17.2016