Is Enalapril 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 Enalapril. The text below is quoted from that source — it is not our own verdict.
Summary of use during breastfeeding
Because of the very low levels of enalapril in breastmilk, amounts ingested by the infant are small and have not been detected in infant serum or caused any adverse effects in a few breastfed infants. If a mother requires enalapril, it is not a reason to discontinue breastfeeding.
Effects on the breastfed infant
None reported in 5 breastfed infants whose mothers were taking oral enalapril 5 to 10 mg daily.[1,2,4]
Effects on milk supply
In 15 postmenopausal hypertensive women (prior lactation status not stated), serum prolactin levels were decreased by 22% compared to placebo after enalapril 20 mg once daily for 15 days.[5] The maternal prolactin level in a mother with established lactation may not affect her ability to breastfeed.
A woman with pre-eclampsia was treated was started at term with oral enalapril 10 mg daily. Her milk came in on day 3 postpartum and she had no difficulties with nursing during 5 weeks of observation.[6]
Levels in milk
Enalapril is an inactive drug that is metabolized to the active metabolite enalaprilat. Enalaprilat is poorly absorbed orally.
Maternal Levels. One mother taking a single oral dose of enalapril 5 mg and 2 mothers taking a single dose 10 mg 3 to 45 days postpartum had undetectable enalaprilat milk levels (<0.2 mcg/L) 4 hours after a single dose; enalapril levels were not determined. The angiotensin converting enzyme activity in milk of all women was within the normal range and unchanged after the dose compared to the predose values.[1]
A woman who had been taking oral enalapril 10 mg daily for 11 months had peak enalapril milk levels of 2 mcg/L 4 hours after a dose and peak enalaprilat levels of 0.75 mcg/L about 9 hours after the dose.[2]
Enalapril and enalaprilat milk levels were determined in 5 women who were in the immediate postpartum period and not breastfeeding. After a single 20 mg oral dose, the average peak enalapril milk level was 1.7 mcg/L (range 0.54 to 5.9 mcg/L) at 4 to 6 hours after the dose. Enalapril was not detectable (assay limit not specified) after 4 hours in 4 of the 5 women. The average peak enalaprilat level was 1.7 mcg/L (range 1.2 to 2.3 mcg/L); peaks occurred at various times over the 24-hour period. The authors estimated that a breastfed infant would receive less than 2 mcg daily of enalaprilat.[3] Using the peak milk level data, the estimated maximum intake of an exclusively breastfed infant would be about 0.16% of the maternal weight-adjusted dosage, half as enalaprilat.
A mother started taking enalapril 5 mg daily for IgA nephropathy at 11 weeks postpartum while exclusively breastfeeding. On day 101 postpartum, 25 days after therapy started, 6 milk samples were collected over the 24 hours after the dose. The estimated RID of enalapril plus enalaprilat was 0.196%.[4]
Infant Levels. A mother started taking enalapril 5 mg daily for IgA nephropathy at 11 weeks postpartum while exclusively breastfeeding. On day 101 postpartum, 25 days after therapy started, one infant blood sample was collected. Infant enalapril and enalaprilat plasma concentrations were below the lower limit of quantification (<0.2 mcg/L).[4]
Alternatives LactMed lists
Enalapril in pregnancy
LactMed covers breastfeeding only. For what the NHS and the US prescribing label say about pregnancy, see:
Source: Drugs and Lactation Database (LactMed), National Institute of Child Health and Human Development (NICHD), via NCBI Bookshelf, record “Enalapril” (LM102). 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.