Is Diphenhydramine safe while breastfeeding?
Here is what NIH LactMed, the U.S. National Library of Medicine's authority on medicines and breastfeeding, reports about Diphenhydramine. This is a summary of that source — not our own verdict.
Effects on the breastfed infant
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. In this study, drowsiness was reported in 1 infant of 12 exposed to diphenhydramine in breastmilk.[ 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 diphenhydramine 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. One woman became dependent on dimenhydrinate (which is 55% diphenhydramine) during her first pregnancy and continued to take it in a dose of 150 mg (83 mg diphenhydramine) daily while she breastfed her infant for 3 months. The infant did well except for a febrile seizure at 2 years of age, which was probably unrelated to dimenhydrinate. During her second pregnancy, she took dimenhydrinate 300 mg (165 mg diphenhydramine) daily during the pregnancy and while breastfeeding her infant for 2 years.[ 5 ]
Levels in milk
Maternal Levels. One old study that used a biologic assay system reported that after a 100 mg intramuscular dose of diphenhydramine in four women, drug levels in milk were undetectable in two and 42 and 100 mcg/L in two others at one hour after the dose. Five hours after the dose, milk levels were undetectable in two women and 20 and 100 mcg/L in two others.[ 1 ] No studies using modern assay methods have been reported. 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.