Furosemide and Breastfeeding

Summary of use during lactation

Because little information is available on the use of furosemide during breastfeeding and because intense diuresis from high doses might decrease lactation, an alternate drug may be preferred, especially while nursing a newborn or preterm infant. Low doses of furosemide (20 mg daily) do not suppress lactation.

Drug levels in milk and infant serum

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

Effects in breastfed infants

Anecdotal, short-term observations at one medical center found no adverse infant effects from maternal use of furosemide in the immediate postpartum period.[1]

Effects on lactation and breastmilk

Furosemide 20 mg intramuscularly on the first postpartum day followed by 40 mg orally for 4 days has been used in conjunction with fluid restriction and breast binding to suppress lactation within 3 days postpartum.[2] The added contribution of furosemide to fluid restriction and breast binding, which are effective in suppressing lactation, is not known. No data exist on the effects of loop diuretics on established lactation. A randomized, controlled trial compared postpartum furosemide (n = 192) to placebo (n = 192) in women who had gestational hypertension and preeclampsia. Patients received either a 4- to 5-day course of 20 mg oral furosemide daily or placebo. The first dose was given 6 to 24 hours postpartum and then every 24 hours thereafter until hospital discharge. No difference was found in patient-reported breastfeeding difficulties between the two groups.[3] A study of mothers with antepartum hypertension were given either furosemide 20 mg or a placebo daily for 5 days postpartum. Mothers reported whether they were exclusively breastfeeding at 2 and 6 weeks postpartum. No difference was found in the rates of exclusive breastfeeding between the furosemide and placebo groups.[4]

Alternative drugs to consider

Chlorothiazide, Hydrochlorothiazide

References

1. Font LM. Breast milk and drugs. MCN Am J Matern Child Nurs 1989;14:308-9.2507852 PubMed
2. Cominos DC, Van Der Walt A, Van Rooyen AJ. Suppression of postpartum lactation with furosemide. S Afr Med J 1976;50:251-2.3858
3. Lopes Perdigao J, Lewey J, Hirshberg A, et al. Furosemide for accelerated recovery of blood pressure postpartum in women with a hypertensive disorder of pregnancy: A randomized controlled trial. Hypertension 2021;77:1517-24.33550824 PubMed
4. Emeruwa UN, Azad H, Ona S, et al. Lasix for the prevention of de novo postpartum hypertension: A randomized placebo-controlled trial (LAPP Trial). Am J Obstet Gynecol 2025;232:e1-125.e21.38823570 PubMed