Is Clemastine safe while breastfeeding?
Here is what NIH LactMed, the U.S. National Library of Medicine's authority on medicines and breastfeeding, reports about Clemastine. This is a summary of that source — not our own verdict.
Effects on the breastfed infant
A 10-week-old breastfed infant whose mother was taking clemastine, phenytoin and carbamazepine was drowsy, refused to feed, was irritable, and had high-pitched crying.[ 1 ] These side effects were possibly caused by clemastine in breastmilk, but the other drugs could also have contributed. In one telephone follow-up study, mothers reported irritability and colicky symptoms 10% of infants exposed to various antihistamines and drowsiness was reported in 1.6% of infants. None of the reactions required medical attention.[ 2 ]
Effects on milk supply
Antihistamines in relatively high doses given by injection can decrease basal serum prolactin in nonlactating women and in early postpartum women.[ 3 , 4 ] However, suckling-induced prolactin secretion is not affected by antihistamine pretreatment of postpartum mothers.[ 3 ] Whether lower oral doses of antihistamines have the same effect on serum prolactin or whether the effects on prolactin have any consequences on breastfeeding success have not been studied. The prolactin level in a mother with established lactation may not affect her ability to breastfeed.
Levels in milk
Maternal Levels. The milk clemastine level was 5 to 10 mcg/L 20 hours after the last dose in a 1 mg twice daily regimen in one woman. A simultaneous serum level was 20 mcg/L.[ 1 ] Infant Levels. Relevant published information was not found as of the revision date.
Alternatives LactMed lists
Source: NIH LactMed (National Library of Medicine).
Educational summary of an authoritative source — not medical advice. Never start, stop, or change a medicine while breastfeeding without confirming with your doctor.