The Basics
What is Diphenhydramine?
In its oral form, it can treat hay fever, allergies, cold symptoms, and insomnia.
Brand names for Diphenhydramine
Benadryl
How Diphenhydramine is classified
Antihistamines
Diphenhydramine During Pregnancy
Diphenhydramine pregnancy category
Category B
Note that the FDA has deprecated the use of pregnancy categories, so for some medications, this information isn’t available. We still think it’s useful to list historical info, however, given what a common proxy this has been in the past.
What we know about taking Diphenhydramine while pregnant
Is diphenhydramine safe for pregnancy? Yes. It’s the antihistamine of choice in pregnancy.
Taking Diphenhydramine While Breastfeeding
What are recommendations for lactation if you're taking Diphenhydramine?
Can you take diphenhydramine while breastfeeding? Small, occasional doses of diphenhydramine would not be expected to cause any adverse effects in breastfed infants. Larger doses or more prolonged use may cause effects in the infant or decrease the milk supply, particularly in combination with a sympathomimetic such as pseudoephedrine or before lactation is well established. Single bedtime doses after the last feeding of the day may be adequate for many women and will minimize any effects of the drug. The nonsedating antihistamines are preferred alternatives.
Maternal / infant drug levels
Small, occasional doses of diphenhydramine would not be expected to cause any adverse effects in breastfed infants. Larger doses or more prolonged use may cause effects in the infant or decrease the milk supply, particularly in combination with a sympathomimetic such as pseudoephedrine or before lactation is well established. Single bedtime doses after the last feeding of the day may be adequate for many women and will minimize any effects of the drug. The nonsedating antihistamines are preferred alternatives.
Possible effects of Diphenhydramine 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]
Possible alternatives to Diphenhydramine
Desloratadine, Fexofenadine, Loratadine.
List of References
Lactation sources: Drugs and Lactation Database (LactMed) [Internet]. Bethesda (MD): National Library of Medicine (US); 2006-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK501922/
1. Rindi V. La eliminazione degli antistaminici di sintesi con il latte e l’azione latto-goga de questi. Riv Ital Ginecol. 1951;34:147-57.
2. Ito S, Blajchman A, Stephenson M et al. Prospective follow-up of adverse reactions in breast-fed infants exposed to maternal medication. Am J Obstet Gynecol. 1993;168:1393-9. PMID: 8498418
3. Messinis IE, Souvatzoglou A, Fais N et al. Histamine H1 receptor participation in the control of prolactin secretion in postpartum. J Endocrinol Invest. 1985;8:143-6. PMID: 3928731
4. Pontiroli AE, De Castro e Silva E, Mazzoleni F et al. The effect of histamine and H1 and H2 receptors on prolactin and luteinizing hormone release in humans: sex differences and the role of stress. J Clin Endocrinol Metab. 1981;52:924-8. PMID: 7228996
5. Kaya FD. A patient with dimenhydrinate dependence: A case report. Klinik Psikofarmakoloji Bulteni. 2014;24:184-7. DOI: doi:10.5455/bcp.20140131023347
Disclaimer: This material is provided for educational purposes only and is not intended for medical advice, diagnosis, or treatment. Consult your healthcare provider with any questions.
