Is Calcitonin safe while breastfeeding?

Summary of use during breastfeeding

Little information is available on the clinical use of calcitonin during breastfeeding; however, calcitonin is a normal component of human milk where may play a role in development of enteric neurons in the breastfed infant.[1-3] Because it is a large peptide, absorption by the infant is unlikely because it is probably destroyed in the infant's gastrointestinal tract. If calcitonin is required by the mother, it is not a necessarily reason to discontinue breastfeeding calcitonin therapy is sometimes used to treat symptomatic postpartum osteoporosis, which is often treated in part by stopping lactation to reduce calcium loss.[4,5] There is no evidence that exogenous calcitonin decreases serum prolactin or lactation in nursing mothers.

Effects on the breastfed infant

A woman with discoid lupus was taking subcutaneous calcitonin 0.5 mL every other day, azathioprine 100 mg daily, warfarin 2.5 mg every 2 days, prednisone 10 mg daily, calcitriol 0.25 mcg every 2 days, acetaminophen 650 mg twice daily, and calcium, vitamin E, and vitamin C. She was specifically evaluated for the safety of azathioprine during lactation, but continued to nurse for 12 months. Infant follow-up at 15 months of age found normal growth and development.[6]

Effects on milk supply

Calcitonin products contain a warning that it should be avoided in nursing mothers because of animal data indicating that calcitonin can lower serum prolactin. The only human data consist of small studies performed in men and nonlactating w omen, some with normal and some with elevated serum prolactin. Several of the studies found a decrease in serum prolactin after calcitonin infusion.[7-10] Another small study found that IV infusion of human calcitonin did not lower serum prolactin in healthy volunteers who had normal serum prolactin at baseline.[11] The prolactin level in a mother with established lactation may not affect her ability to breastfeed.

Levels in milk

Maternal Levels. Relevant published information was not found as of the revision date.

Infant Levels. Relevant published information was not found as of the revision date.