Key Findings: Antihistamines and Birth Defects
Main findings from this study
- Scientific research suggests that using most types of antihistamines during pregnancy is not linked to birth defects.
- Out of 54 studies examined, 9 studies showed potential links between certain antihistamines and certain birth defects. Researchers need to study these potential links further.
- Researchers found many studies on antihistamine medications typically used to treat allergies, asthma, or nausea and vomiting (H1-receptor antagonists).
- Examples of H1-receptor antagonists include diphenhydramine (Benadryl®), dimenhydrinate (Dramamine®), loratadine (Claritin®), and cetirizine (Zyrtec ®).
- In contrast, researchers found relatively few studies on antihistamines typically used to treat indigestion (H2-receptor antagonists).
- Examples of H2-receptor antagonists include ranitidine (Zantac®), famotidine (Pepcid®), and cimetidine (Tagamet®).
About antihistamines and this study
- Asthma and/or allergies;
- Nausea and vomiting; or
- Indigestion (heartburn or stomach ache).
About this study
Treating for Two: Safer Medication Use in Pregnancy
- Research: CDC funds the Centers for Birth Defects Research and Prevention, which collaborate on large studies such as the National Birth Defects Prevention Study (births 1997-2011) and the Birth Defects Study To Evaluate Pregnancy exposures (started with births in 2014). Researchers engaging in these studies work to identify factors that increase the risk for birth defects and to answer questions about the effects of some medications taken during pregnancy.
- Technical expertise: CDC works with staff from the U.S. Food and Drug Administration (FDA) and other professionals to help conduct studies on the effects of medication use during pregnancy and ways to prevent harmful effects.
- Collaboration: As part of the Treating for Two: Safer Medication Use in Pregnancy Initiative, CDC is committed to working with its partners, other federal agencies, and the public to build a comprehensive approach to improve the quality of data on medication use during pregnancy, translate this information into safe and effective health care for pregnant women, and make this information easily accessible to women and their healthcare providers.