Are Antihistamines (Benadryl, Zyrtec, Claritin) Safe During Pregnancy?

Your eyes have been streaming since Tuesday and you got through half a box of tissues before lunch. The medicine that used to take care of this is in the drawer, and the pregnancy line on the back of the box tells you to ask a doctor and then stops.

Several of the usual ones come out fine, so this is a smaller worry than the packaging makes it feel. What to watch is which family you are holding, what you are using it for, and what else the manufacturer put in the same box. The families are the place to start.

The two families of antihistamines

Several antihistamines are generally considered acceptable in pregnancy, and which one suits you starts with which generation it belongs to. Older “first generation” ones tend to cause drowsiness. Newer “second generation” ones are designed to be non-drowsy and are usually better for everyday allergy control.

• First generation (can cause drowsiness): diphenhydramine (Benadryl) and chlorpheniramine. These have been used for a long time and are generally considered low risk in pregnancy when used as needed.
• Second generation (non-drowsy): loratadine (Claritin) and cetirizine (Zyrtec). These are commonly considered reasonable choices for ongoing allergy symptoms and are easier to take during the day.

Which one suits you depends on your symptoms, how far along you are, and your history, which is exactly why a quick check with your provider or pharmacist is worth it before you start something new.

Sensible cautions

• Pick single-ingredient products. Many allergy and cold medicines are combinations that also contain decongestants (like pseudoephedrine or phenylephrine) or pain relievers. Decongestants have their own pregnancy cautions, especially in the first trimester, so a plain antihistamine is usually the cleaner choice.
• Do not lean on them for sleep. Diphenhydramine is sold in many sleep aids. Using it occasionally for allergies is different from taking it nightly to sleep, which is not a good long-term plan in pregnancy. Talk to your provider about pregnancy-safe sleep strategies instead, and melatonin in pregnancy covers the other thing people reach for at 2 a.m.
• Near your due date, mention any regular antihistamine use to your provider, as timing around labor can occasionally matter.
• Use the lowest dose that works, for as long as you actually need it.

Non-medication relief that helps

For nasal allergies and congestion, saline nasal sprays or rinses, a humidifier, and avoiding known triggers can take the edge off without any medication. Many providers also consider steroid nasal sprays acceptable in pregnancy for ongoing nasal allergies, so ask about those if simple measures are not enough.

When to call your provider

Get prompt advice if you have a severe allergic reaction (especially any swelling of the lips, tongue, or throat, or trouble breathing, which is an emergency), if hives are widespread or persistent, if your symptoms are not controlled, or if you are unsure which product is right for you. For everyday questions, your pharmacist is a quick and knowledgeable resource.

If you have found something non-medicated that genuinely helps, say so in the comments. The saline rinse you finally got the hang of, the pillowcase you started washing twice a week, the week you gave in and kept the windows shut. Allergy season comes round again for whoever reads this next spring.

Medical Disclaimer: This article is for general educational purposes only and is not medical advice, and it does not replace guidance from your doctor, midwife, or pharmacist. Medication recommendations depend on your individual history, so always confirm what is safe for you with a qualified professional. If you think you may be experiencing a medical emergency, contact your local emergency services right away.

Sources

• American College of Obstetricians and Gynecologists (ACOG). Guidance on allergy and cold medicine use in pregnancy.
• Organization of Teratology Information Specialists (MotherToBaby). Fact sheets on diphenhydramine, loratadine, and cetirizine in pregnancy.
• National Health Service (NHS). “Antihistamines in pregnancy.” 2024.