Can I take amitriptyline for pain and migraine while pregnant or breastfeeding?

Pregnancy Category C Teratogenic effects were not observed in mice, rats, or rabbits when amitriptyline was given orally at doses of 2 to 40 mg/kg/day (up to 13 times the maximum recommended human dose 1 ). Studies in literature have shown amitriptyline to be teratogenic in mice and hamsters when given by various routes of administration at doses of 28 to 100 mg/kg/day (9 to 33 times the maximum recommended human dose), producing multiple malformations. Another study in the rat reported that an oral dose of 25 mg/kg/day (8 times the maximum recommended human dose) produced delays in ossification of fetal vertebral bodies without other signs of embryotoxicity. In rabbits, an oral dose of 60 mg/kg/day (20 times the maximum recommended human dose) was reported to cause incomplete ossification of cranial bones. Amitriptyline has been shown to cross the placenta. Although a causal relationship has not been established, there have been a few reports of adverse events, including CNS effects, limb deformities, or developmental delay, in infants whose mothers had taken amitriptyline during pregnancy. There are no adequate and well-controlled studies in pregnant women.

Prescribing label, section “Pregnancy” (opening excerpt): Amitriptyline Hydrochloride (oral), American Health Packaging. Read the full section on DailyMed. Quoted verbatim; US labels are written for US prescribers and patients.

Milk levels of amitriptyline and its metabolites are low. Immediate side effects have not been reported and a limited amount of follow-up has found no adverse effects on infant growth and development. Amitriptyline use during breastfeeding would usually not be expected to cause any adverse effects in breastfed infants, especially if the infant is older than 2 months. A safety scoring system finds amitriptyline use to be possible with caution during breastfeeding.[1] However, rare sedation has been reported in a neonate. Other agents with fewer active metabolites may be preferred when large doses are required or while nursing a newborn or preterm infant.

“Summary of Use during Lactation”, LactMed record “Amitriptyline” (LM312), quoted verbatim. Everything LactMed reports about Amitriptyline while breastfeeding.

Nursing Mothers Amitriptyline is excreted into breast milk. In one report in which a patient received amitriptyline 100 mg/day while nursing her infant, levels of 83 to 141 ng/mL were detected in the mother's serum. Levels of 135 to 151 ng/mL were found in the breast milk, but no trace of the drug could be detected in the infant's serum. Because of the potential for serious adverse reactions in nursing infants from amitriptyline, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

Prescribing label, section “Nursing Mothers”: Amitriptyline Hydrochloride (oral), American Health Packaging. Label on DailyMed. Quoted verbatim; US labels are written for US prescribers and patients.