Drug Levels and Effects:

Summary of Use during Lactation:

Because of the minimal amount of information on this potent agent, use minoxidil with caution, particularly when therapy involves a large dosage or in newborns. Topical minoxidil should pose low risk to the breastfed infant.

Drug Levels:

Maternal Levels.

In one case report, a 2-month-postpartum mother who was taking minoxidil 5 mg twice daily was given a, oral dose of 7.5 mg. The peak milk level of minoxidil plus glucuronide conjugate was 45.1 mcg/L at 1 hour after the dose. Milk levels paralleled serum levels, falling rapidly after the first hour to a concentration of 12.4 mcg/L at 3 hours, 4 mcg/L at 6 hours, 1.9 mcg/L at 9 hours, 0.8 mcg/L at 12 hours after the dose. [1]

Infant Levels.

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

Effects in Breastfed Infants:

No hypertrichosis or other abnormal signs were seen in one infant breastfed for 2 months of maternal minoxidil therapy.[1]

Possible Effects on Lactation:

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

Alternate Drugs to Consider:



1. Valdivieso A, Valdes G, Spiro TE et al. Minoxidil in breast milk. Ann Intern Med. 1985;102:135. Letter. PMID:3966734

Substance Identification:

Substance Name:


CAS Registry Number:


Drug Class:

  • Antihypertensive Agents

  • Vasodilator Agents

  • Administrative Information:

    LactMed Record Number:


    Last Revision Date:

    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.