Can I take nifedipine while pregnant or breastfeeding?

Pregnancy Pregnancy Category C. In rodents, rabbits and monkeys, nifedipine has been shown to have a variety of embryotoxic, placentotoxic, teratogenic and fetotoxic effects, including stunted fetuses (rats, mice and rabbits), digital anomalies (rats and rabbits), rib deformities (mice), cleft palate (mice), small placentas and underdeveloped chorionic villi (monkeys), embryonic and fetal deaths (rats, mice and rabbits), prolonged pregnancy (rats; not evaluated in other species), and decreased neonatal survival (rats; not evaluated in other species). On a mg/kg or mg/m 2 basis, some of the doses associated with these various effects are higher than the maximum recommended human dose and some are lower, but all are within an order of magnitude of it. The digital anomalies seen in nifedipine-exposed rabbit pups are strikingly similar to those seen in pups exposed to phenytoin, and these are in turn similar to the phalangeal deformities that are the most common malformation seen in human children with in utero exposure to phenytoin. From the clinical evidence available, a specific prenatal risk has not been identified.

Prescribing label, section “Pregnancy” (opening excerpt): Nifedipine (oral), Golden State Medical Supply, Inc. Read the full section on DailyMed. Quoted verbatim; US labels are written for US prescribers and patients.

Because of the low levels of nifedipine in breastmilk, amounts ingested by the infant are small, even in women with a genetic variant of breast cancer resistance protein that increases the amount of drug transferred to milk. No adverse effects have been reported among infants exposed to nifedipine in breastmilk. Nifedipine is used to treat painful nipple vasospasm (e.g., Raynaud phenomenon) in nursing mothers who do not respond to other measures such as hot compresses and avoidance of cold exposure.[1-6] The dosages of nifedipine most commonly reportedly used to treat the condition is 20 to 60 mg daily either as a single dose of a sustained-release product or 10 to 20 mg 3 times daily of an immediate-release product. Lower dosages can be tried if these doses are not tolerated.

“Summary of Use during Lactation”, LactMed record “Nifedipine” (LM198), quoted verbatim. Everything LactMed reports about Nifedipine while breastfeeding.

Nursing Mothers Nifedipine is excreted in human milk. Nursing mothers are advised not to breastfeed their babies when taking the drug.

Prescribing label, section “Nursing Mothers”: Nifedipine (oral), Golden State Medical Supply, Inc. Label on DailyMed. Quoted verbatim; US labels are written for US prescribers and patients.