Is Amlodipine (calcium channel blocker) safe to use in a breastfeeding woman with hypertension?

Amlodipine Safety During Breastfeeding

Amlodipine is safe to use during breastfeeding, with minimal infant exposure (median relative infant dose of 4.2%, well below the 10% safety threshold), and is recommended as a first-line antihypertensive agent for postpartum hypertension in nursing mothers. 1

First-Line Medication Status

• The American Heart Association explicitly recommends amlodipine as a first-line agent for postpartum hypertension regardless of breastfeeding status. 1

• Amlodipine is listed alongside nifedipine, enalapril, and labetalol as preferred options for breastfeeding mothers with hypertension. 1

• The European Society of Cardiology also endorses amlodipine as safe for breastfeeding mothers. 1, 2

Breast Milk Transfer and Infant Safety

• Amlodipine transfers into breast milk at levels similar to maternal plasma (milk-to-plasma ratio approximately 0.85-1.4), but the absolute amounts are very low. 3, 4

• The relative infant dose (RID) is 4.2% (range 3.1%-7.3%), which is well below the 10% threshold generally considered concerning for infant safety. 1, 3

• Multiple studies have demonstrated that amlodipine concentrations in infant plasma are either undetectable or below the quantitation limit (<0.4 ng/mL), indicating negligible systemic exposure in breastfed infants. 4, 5

• No adverse effects have been reported in breastfed infants whose mothers were taking amlodipine. 6, 4

Practical Advantages

• Amlodipine offers once-daily dosing, which significantly improves medication adherence compared to agents requiring multiple daily doses. 1

• This is particularly valuable in the postpartum period when new mothers face numerous competing demands on their time and attention. 1

Alternative First-Line Options

If amlodipine is not tolerated or contraindicated, other first-line alternatives for breastfeeding mothers include:

• Extended-release nifedipine (another calcium channel blocker with once-daily dosing and excellent safety profile). 1, 2

• Labetalol or propranolol (if a beta-blocker is specifically indicated; note that atenolol should be avoided). 1

• Enalapril (ACE inhibitor; safe during lactation but contraindicated during pregnancy). 1

Medications to Avoid or Use Cautiously

• Diuretics may reduce milk volume and suppress lactation, especially at higher doses, and should generally be avoided in breastfeeding women. 7, 1

• Atenolol should be avoided due to higher risk of adverse effects compared to other beta-blockers. 1

Monitoring Requirements

• All breastfed infants of mothers taking antihypertensive agents should be monitored for potential adverse effects, though none have been reported with amlodipine specifically. 7, 1

• Blood pressure should be checked at 6 weeks postpartum to confirm persistent hypertension and guide ongoing treatment decisions. 1

Special Consideration for Mild Hypertension

• For mothers with stage 1 hypertension who plan to breastfeed for only a few months, it may be reasonable to withhold antihypertensive medication with close blood pressure monitoring and reinstitute therapy after discontinuing nursing. 7, 1

• However, this approach requires careful individualized assessment and close follow-up to prevent progression to severe hypertension.

FDA Labeling Information

• The FDA label confirms that amlodipine is present in human milk at an estimated median relative infant dose of 4.2%, with no adverse effects observed in breastfed infants. 6

• There is no available information on the effects of amlodipine on milk production. 6