Is Chlorothiazide 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 Chlorothiazide. The text below is quoted from that source — it is not our own verdict.
Summary of use during breastfeeding
Amounts of chlorothiazide in milk are low, but high doses might suppress lactation. Low-dose chlorothiazide appears to be acceptable during lactation. Intense diuresis with large doses may decrease breastmilk production.
Effects on the breastfed infant
Relevant published information was not found as of the revision date.
Effects on milk supply
Relevant published information on chlorothiazide was not found as of the revision date. Intense diuresis with thiazides and thiazide-like diuretics, fluid restriction and breast binding have been used to suppress postpartum lactation.[2-4] The added contribution of the diuretic to these measures, which are effective in suppressing lactation, has not been studied. There are no data on the effects of diuretics on established, ongoing lactation.
Levels in milk
Maternal Levels. After a single dose of 500 mg of chlorothiazide orally, there was no detectable drug (<1 mg/L) in the breastmilk from 11 nursing mothers at 1, 2 and 3 hours after the dose.[1]
Infant Levels. Relevant published information was not found as of the revision date.
Alternatives LactMed lists
Source: Drugs and Lactation Database (LactMed), National Institute of Child Health and Human Development (NICHD), via NCBI Bookshelf, record “Chlorothiazide” (LM63). 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.