Is Misoprostol safe while breastfeeding?
Here is what LactMed, the Drugs and Lactation Database published by the U.S. National Institute of Child Health and Human Development (NICHD), reports about Misoprostol. The text below is quoted from that source — it is not our own verdict.
Summary of use during breastfeeding
Misoprostol is a prostaglandin E1 analogue. Prostaglandin E1 and other prostaglandins appear normally in colostrum and milk.[1] Because of the extremely low levels of misoprostol in breastmilk, amounts ingested by the infant are trivial and would not be expected to cause any adverse effects in breastfed infants. No special precautions are required.
Effects on the breastfed infant
Relevant published information was not found as of the revision date.
Effects on milk supply
Relevant published information was not found as of the revision date.
Levels in milk
After absorption, misoprostol is rapidly converted into misoprostol acid in the liver. Studies of misoprostol measure misoprostol acid in the colostrum or milk.
Maternal Levels. Twenty women received misoprostol 600 mcg orally during the first 4 days postpartum. Twelve of them collected a total of 24 colostrum samples at various times during the first 5 hours after the dose. The average misoprostol concentration was highest in colostrum 1 hour after the dose at 20.9 ng/L. Average concentrations fell to 17.8 ng/L at 2 hours after the dose, 9.4 ng/L at 3 hours, 2.8 ng/L at 4 hours and <1 ng/L at 5 hours after the dose.[2]
Ten women who averaged 3.9 days postpartum received a single oral dose of misoprostol 200 mcg. Milk samples were obtained from one breast from 0.5 to 5 hours after the dose. The mean and median peak milk levels were 7.6 and 3.6 ng/L, respectively, at 1.1 hours after the dose. In 2 women, the peak milk level occurred 2 hours after the dose. By 5 hours, the median milk level was 0.2 ng/L. The half-life in milk averaged 1.1 hours.[3]
Infant Levels. Relevant published information was not found as of the revision date.
Alternatives LactMed lists
“No published information” means the studies do not exist yet — not that Misoprostol is known to be harmful, and not that it is known to be safe. Your prescriber or pharmacist can weigh your baby's age and whether a better-studied alternative would do the same job. Worth asking before stopping a medicine you need.
Source: Drugs and Lactation Database (LactMed), National Institute of Child Health and Human Development (NICHD), via NCBI Bookshelf, record “Misoprostol” (LM554). LactMed on NCBI Bookshelf. LactMed is a registered trademark of the U.S. Department of Health and Human Services.
Educational summary of an authoritative source — not medical advice. Never start, stop, or change a medicine while breastfeeding without confirming with your doctor.