U.S. flag

An official website of the United States government

NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.

Drugs and Lactation Database (LactMed) [Internet]. Bethesda (MD): National Library of Medicine (US); 2006-.

Cover of Drugs and Lactation Database (LactMed)

Drugs and Lactation Database (LactMed) [Internet].

Show details


Last Revision: July 18, 2022.

Estimated reading time: 2 minutes

CASRN: 52-01-7

image 134972759 in the ncbi pubchem database

Drug Levels and Effects

Summary of Use during Lactation

Limited data indicate that spironolactone is poorly excreted into breastmilk. Case of mothers breastfeeding during spironolactone therapy reported no adverse effects in infants. Spironolactone appears to be acceptable to use during breastfeeding.

Drug Levels

Maternal Levels. The major metabolite of spironolactone, canrenone, was measured in the serum and milk of a 17-day postpartum woman who was taking 25 mg of spironolactone four times daily. Milk canrenone levels 2 hours after the dose were 104 mcg/L, and 47 mcg/L at 14.5 hours after the dose. The authors estimated that the nursing infant would receive about 0.2% of the mother's total daily dosage in the form of canrenone.[1] Active sulfur-containing metabolites were not measured.

Infant Levels. Relevant published information was not found as of the revision date.

Effects in Breastfed Infants

In 17-day-old breastfed (extent not stated) infant whose mother was taking 25 mg of spironolactone 4 times daily since pregnancy, serum sodium and potassium remained normal.[1]

Spironolactone 75 mg every other day was taken orally by a mother while nursing a newborn. She was also taking 400 mg of bretylium tosylate every 8 hours, atenolol 25 mg daily, propranolol 20 mg 3 times a day, and multivitamin, potassium and magnesium supplements. Jaundice, thought to be unrelated to the drug, occurred at 60 hours of age, but resolved. The infant had appropriate weight gain and development during the first 4 months of life.[2]

A transgender woman took and spironolactone 50 mg twice daily to suppress testosterone, domperidone 10 mg three times daily, increasing to 20 mg four times daily, oral micronized progesterone 200 mg daily and oral estradiol to 8 mg daily and pumped her breasts 6 times daily to induce lactation. After 3 months of treatment, estradiol regimen was changed to a 0.025 mg daily patch and the progesterone dose was lowered to 100 mg daily. Two weeks later, she began exclusively breastfeeding the newborn of her partner. Breastfeeding was exclusive for 6 weeks, during which the infant's growth, development and bowel habits were normal. The patient continued to partially breastfeed the infant for at least 6 months.[3]

A wonam with Gitleman syndrome took spironolactone in an unspecified dosage along with potassium and magnesium supplements for at least 4 months while breastfeeding her infant. No adverse infant effets were reported.[4]

Effects on Lactation and Breastmilk

Intense diuresis can suppress lactation;[5,6] however, it is unlikely that spironolactone alone is sufficiently potent to cause this effect.

Spironolactone can cause gynecomastia. The estimated risk is 52 cases per 1000 patients treated, which is 8.4 times the baseline risk.[7]


Phelps DL, Karim A. Spironolactone: Relationship between concentrations of dethioacetylated metabolite in human serum and milk. J Pharm Sci. 1977;66:1203. [PubMed: 894512]
Gutgesell M, Overholt E, Boyle R. Oral bretylium tosylate use during pregnancy and subsequent breastfeeding: A case report. Am J Perinatol. 1990;7:144–5. [PubMed: 2331276]
Reisman T, Goldstein Z. Case report: Induced lactation in a transgender woman. Transgend Health. 2018;3:24–6. [PMC free article: PMC5779241] [PubMed: 29372185]
de Jong MFC, Riphagen IJ, Kootstra-Ros JE, et al. Potassium and magnesium in breast milk of a woman with Gitelman syndrome. Kidney Int Rep. 2022;7:1720–1. [PMC free article: PMC9263202] [PubMed: 35812288]
Healy M. Suppressing lactation with oral diuretics. Lancet. 1961;277:1353–4.
Cominos DC, Van Der Walt A, Van Rooyen AJ. Suppression of postpartum lactation with furosemide. S Afr Med J 1976;50:251-2. PMID: 3858. [PubMed: 3858]
Trinchieri A, Perletti G, Magri V, et al. Drug-induced gynecomastia: A systematic review and meta-analysis of randomized clinical trials. Arch Ital Urol Androl. 2021;93:489–96. [PubMed: 34933535]

Substance Identification

Substance Name


CAS Registry Number


Drug Class

Breast Feeding


Milk, Human

Antihypertensive Agents


Mineralocorticoid Receptor Antagonists

Disclaimer: Information presented in this database is not meant as a substitute for professional judgment. You should consult your healthcare provider for breastfeeding advice related to your particular situation. The U.S. government does not warrant or assume any liability or responsibility for the accuracy or completeness of the information on this Site.


Related information

Similar articles in PubMed

See reviews...See all...

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...