Spironolactone

Pregnancy

The use of spironolactone is best avoided during pregnancy because there is no evidence from human studies that have investigated whether spironolactone use is safe during pregnancy or not.

Category: C

Category A

Adequate and well-controlled studies have failed to demonstrate a risk to the fetus in the first trimester of pregnancy (and there is no evidence of risk in later trimesters).

Category B

Animal reproduction studies have failed to demonstrate a risk to the fetus and there are no adequate and well-controlled studies in pregnant women.

Category C

Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

Category D

There is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience or studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

Category X

Studies in animals or humans have demonstrated fetal abnormalities and/or there is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience, and the risks involved in use of the drug in pregnant women clearly outweigh potential benefits.

Breastfeeding

Excreted into human milk: Yes – as an active metabolite (Canrenone)

Canrenone, which is the active metabolite of spironolactone was found in breast milk, which suggests that when breastfeeding mothers use spironolactone, it may be passed on to the baby through their breast milk. However, whether this is harmful to the infant is unknown.

There is limited and conflicting data to gauge the effects of spironolactone on the quality and production of breast milk. If you are breastfeeding, speak with your physician before you take spironolactone.