What antihypertensive (blood pressure-lowering) medications are safe for breastfeeding mothers?

From the Guidelines

Breastfeeding mothers can safely use antihypertensive medications such as nifedipine, enalapril, amlodipine, labetalol, and hydrochlorothiazide, which have a relative infant dose (RID) of less than 10% and are considered safe for lactation. When selecting an antihypertensive for a breastfeeding mother, it's essential to choose medications with a proven safety record, as indicated in the study published in Circulation in 2025 1. The study provides a comprehensive list of antihypertensive medications that are safe for breastfeeding mothers, including their maximum doses and RID levels.

Key Considerations

• Nifedipine, a calcium channel blocker, has an RID of 2.3%-3.4% and is considered safe for breastfeeding mothers, with a maximum dose of 120 mg/day or 60 mg twice a day 1.
• Enalapril, an ACE inhibitor, has an RID of 1.1% and is considered safe for breastfeeding mothers, with a maximum dose of 40 mg/day or 20 mg twice a day 1.
• Amlodipine, a calcium channel blocker, has an RID of 1.7%-A.3% and is considered safe for breastfeeding mothers, with a maximum dose of 10 mg/day 1.
• Labetalol has an RID of 3.6% and is considered safe for breastfeeding mothers, with a maximum dose of 200 mg/day 1.
• Hydrochlorothiazide, a thiazide diuretic, has an RID of 0.6%-1.2% and is considered safe for breastfeeding mothers, but may decrease breastmilk production at doses above 25 mg/day, with a maximum dose of 200 mg/day 1.

Monitoring and Medication Timing

• Blood pressure should be monitored regularly in breastfeeding mothers taking antihypertensive medications.
• Medication timing can be optimized by taking doses immediately after breastfeeding or before the infant's longest sleep period to minimize exposure.
• The benefits of treating maternal hypertension typically outweigh the minimal risks to the breastfed infant, as indicated in the study published in the European Heart Journal in 2020 1.

From the FDA Drug Label

Limited available data from a published clinical lactation study reports that amlodipine is present in human milk at an estimated median relative infant dose of 4.2%. No adverse effects of amlodipine on the breastfed infant have been observed. Propranolol is excreted in human milk. Caution should be exercised when propranolol hydrochloride extended-release capsules are administered to a nursing woman

Antihypertensives that are safe for breast feeding mothers:

• Amlodipine: may be safe, as the estimated median relative infant dose is 4.2% and no adverse effects have been observed 2
• Propranolol: use with caution, as it is excreted in human milk and may pose a risk to the infant 3

From the Research

Antihypertensives Safe for Breastfeeding Mothers

• Methyldopa is considered safe for use during breastfeeding, as it has a low milk to plasma (M/P) ratio 4
• Beta-blockers with high protein binding are also considered safe for breastfeeding mothers 4
• Some calcium channel blockers, such as amlodipine and nifedipine, are safe for use during breastfeeding, with minimal excretion in breast milk 5, 4, 6
• Angiotensin-converting enzyme (ACE) inhibitors, such as enalapril, are safe for use during breastfeeding, with minimal excretion in breast milk 5, 4
• Beta-blockers with low protein binding should be avoided during breastfeeding due to high M/P ratios 4
• Diuretics, atenolol, and other beta-blockers are not recommended for antihypertensive purposes during pregnancy and breastfeeding 5
• Renin-angiotensin-aldosterone system inhibitors are strictly contraindicated during pregnancy, but may be safe during breastfeeding 5

Comparison of Antihypertensive Medications

• Nifedipine and amlodipine are comparably safe and effective treatment options for mild-to-moderate essential hypertension 6
• The efficacy and safety of antihypertensive medications during pregnancy and breastfeeding may vary depending on the specific medication and individual patient factors 5, 4, 7, 8