Is Tolbutamide 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 Tolbutamide. The text below is quoted from that source — it is not our own verdict.
Summary of use during breastfeeding
Tolbutamide is no longer marketed in the United States. It is excreted into breastmilk in small amounts that should cause no harm to the breastfed infant. Monitor breastfed infants for signs of hypoglycemia such as jitteriness, excessive sleepiness, poor feeding, seizures cyanosis, apnea, or hypothermia. If there is concern, monitoring of the breastfed infant's blood glucose is advisable during maternal therapy with hypoglycemic agents.[1,2]
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
Maternal Levels. In 2 women who were 3 days postpartum, milk levels were measured 4 hours after ingestion of a 500 mg dose of tolbutamide. Milk levels averaged 18 mg/L in one and 3 mg/L in the other.[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 Tolbutamide 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 “Tolbutamide” (LM262). 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.