What is the best antihypertensive medication for a lactating (breastfeeding) woman?

From the Guidelines

Labetalol is the best antihypertensive medication for a lactating woman, as it effectively controls blood pressure with minimal transfer into breast milk, making it safe for the nursing infant. According to the most recent and highest quality study 1, labetalol has a relative infant dose (RID) of 3.6%, which is considered safe. The study suggests that labetalol can be started at a dose of 25 mg twice daily and titrated up to 200-400 mg twice daily as needed for blood pressure control. Other options, such as nifedipine and enalapril, may also be considered, but labetalol is generally preferred due to its safety profile and effectiveness. Some key points to consider when selecting an antihypertensive medication for a lactating woman include:

• The medication's safety profile, including its RID and potential effects on the nursing infant
• The medication's effectiveness in controlling blood pressure
• The need to monitor blood pressure regularly and adjust the medication dose as needed
• The potential for drug interactions and side effects
• The importance of coordinating medication timing with breastfeeding to minimize infant exposure. Medications to avoid during lactation include angiotensin receptor blockers (ARBs) and direct renin inhibitors, as they may have adverse effects on the nursing infant 1. Overall, the goal is to balance the mother's need for hypertension control with the safety of the breastfeeding infant, and labetalol is generally considered the best option for achieving this balance.

From the FDA Drug Label

Methyldopa appears in breast milk. Therefore, caution should be exercised when methyldopa is given to a nursing woman. Small amounts of labetalol (approximately 0.004% of the maternal dose) are excreted in human milk. Caution should be exercised when TRANDATE Tablets are administered to a nursing woman.

Best Antihypertensive for Lactating Women:

• Methyldopa and labetalol are both present in breast milk, but the amount of labetalol is relatively small (approximately 0.004% of the maternal dose) compared to methyldopa.
• Considering the available information, labetalol may be a preferable option for lactating women due to the smaller amount excreted in breast milk.
• However, it is essential to exercise caution when administering either medication to a nursing woman, and the decision should be made on a case-by-case basis, taking into account the individual patient's needs and circumstances 2 3.

From the Research

Antihypertensive Medications for Lactating Women

• The safety of antihypertensive medications during lactation is a concern, as some drugs may be excreted in breast milk and potentially harm the infant 4.
• Studies have shown that certain antihypertensive medications, such as ACE inhibitors, methyldopa, beta-blockers with high protein binding, and some calcium channel blockers, appear to be safe for use during lactation 4, 5.
• Beta-blockers with low protein binding, on the other hand, may have higher milk to plasma ratios and should be avoided 4.
• Other studies have suggested that nifedipine and amlodipine may be safe for use during lactation, with minimal excretion in breast milk 5, 6.
• Methyldopa, labetalol, and nifedipine are commonly used antihypertensive medications during pregnancy and postpartum, and can be continued during lactation if necessary 5, 7, 6.

Specific Medications

• Methyldopa: considered safe for use during lactation, with low milk to plasma ratios 4, 5, 7.
• Labetalol: considered safe for use during lactation, with low milk to plasma ratios 4, 5, 7, 6.
• Nifedipine: considered safe for use during lactation, with minimal excretion in breast milk 5, 6.
• Amlodipine: considered safe for use during lactation, with minimal excretion in breast milk 5.
• ACE inhibitors: considered safe for use during lactation, with low milk to plasma ratios 4, 5.
• Beta-blockers with high protein binding: considered safe for use during lactation, with low milk to plasma ratios 4.
• Beta-blockers with low protein binding: should be avoided during lactation, due to higher milk to plasma ratios 4.