Hydroxyzine should be limited during the first trimester of pregnancy.
Hydroxyzine is an antihistamine that’s used mostly as an “as-needed" medication for severe itching, anxiety, or insomnia. Antihistamines are generally considered safe in pregnancy; however, studies using hydroxyzine in rats early in pregnancy did show an increased risk of fetal abnormalities. While this hasn’t been replicated in human studies, it’s probably best to refrain from frequent use in the first trimester if possible.
This medication is used commonly in the second and third trimester for the aforementioned reasons and is generally considered safe during these portions of the pregnancy. If you’re using hydroxyzine to treat anxiety, please speak with your obstetrical provider, as there are many safe and effective ways to treat anxiety even early in pregnancy.