Ugh, These Allergies

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Is Zyrtec Safe During Pregnancy? OB-GYNs Recommend It Often

Stupid pollen.

Sick of feeling stuffy and snotty? Yeah, seasonal allergies will do that to you. And when you’re pregnant during the spring — or you’re exposed to any allergens while you happen to be pregnant — the symptoms can feel even worse than usual. So naturally you’re curious about the best antihistamine to take while pregnant, or wondering if the Zyrtec in your medicine cabinet is safe to take right now. Here, two OB-GYNs answer all your burning questions about treating your allergy symptoms while also trying to grow a whole new person.

Is Zyrtec safe during pregnancy?

Doctors agree that Zyrtec (generic name: cetirizine) is a safe, effective medicine to take for allergy relief during any trimester of your pregnancy. “Similar to Claritin, it is one of our first line go-tos for allergies in pregnancy,” says Dr. Clayton Alfonso, M.D., board-certified OB-GYN at Duke Health. “There are no documented pregnancy risks with Zyrtec.”

That said, you should be mindful of what other medications you’re taking at the same time as Zyrtec, says Dr. Sarah Ziebarth, M.D., OB-GYN at Methodist Le Bonheur Healthcare.

“Zyrtec is one of the most well-studied classes of medicines in pregnancy, and it’s very commonly used in pregnancy. We actually have some data with human studies using Zyrtec, even in the first trimester that are very reassuring,” she says. “We need to know what other medications you’re on because a lot of the medications we commonly use in pregnancy are also in the same class as Zyrtec — they’re antihistamines — and we need to make sure you’re not doubling up on them.”

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Two such medications would be Phenergan (generic name: promethazine) and doxylamine, both of which are used to treat nausea and vomiting in pregnancy, Ziebarth says. “Taken in addition to Zyrtec, you may get more pronounced side effects,” she notes.

Can you take Zyrtec-D while pregnant?

Zyrtec-D combines cetirizine with a nasal decongestant called pseudoephedrine. In animal trials, pseudoephedrine has been linked with birth defects, especially when used in the first trimester, according to the National Library of Medicine. Because of this, OB-GYNs want pregnant people to avoid taking any medication containing the compound.

“Pseudoephedrine we would definitely try to avoid in pregnancy if at all possible,” Alfonso says.

Ziebarth agrees that medications containing pseudoephedrine aren’t ideal for pregnant people, but in the event taking one was necessary, your OB-GYN would likely monitor you more closely during that time.

“I won’t do a blanket statement that there’s never an indication for a pregnant person to take that, but pseudoephedrine is in a class of medications that can cause vasoconstriction (shrinking of the blood vessels). The thought is that that may also be occurring in the placenta, decreasing blood flow to the fetus,” she says.

So, before you take Zyrtec-D, be sure to run it by your OB-GYN first.

Which antihistamine is best in pregnancy?

If you’re trying to choose between a few different allergy medicines, know that there’s not one top dog — just a bunch of safe, OB-approved options.

“The three most common ones that people probably use are Claritin, Zyrtec, and Allegra,” Alfonso says. “They’re all pretty equal in getting the job done from an allergic rhinitis standpoint. Those medications tend to be non-sedating compared to the first generation antihistamines like Benadryl, which is safe in pregnancy but tends to cause drowsiness. People tend to stay away from that, especially if they have to like work or drive.”

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Which antihistamine is “best” comes down to personal preference, Ziebarth says. “As far as the safety profile, all of the antihistamines would be acceptable. When you’re looking for the best fit for a particular patient, we’re looking at the duration of the medication and the side effects. Zyrtec is formulated to cause less drowsiness, so that’s one benefit of the longer acting antihistamines like Zyrtec and Claritin.”

How much Zyrtec should you take while pregnant?

You might think you should take less Zyrtec than usual when you’re expecting, but doctors say to just stick to the dosage on the box. The guidance will vary based on which formulation you have (like tablets versus chewables or liquid gels).

“There aren’t any dose adjustments for pregnancy, so you can follow the standard manufacturer guidelines on the bottle,” says Ziebarth.

When to take Zyrtec while pregnant

Feeling your nose start to run or your eyes starting to itch? Whatever your usual allergy symptoms are, those are still a sign it’s time for an antihistamine. “Zyrtec is most commonly used for allergy symptoms, like runny nose or congestion associated with environmental allergies. There’s also some benefit to using it for patients with asthma, because it helps with inflammation in the respiratory system,” says Ziebarth.

If an antihistamine alone isn’t doing the trick, ask your OB-GYN what you can try next.

“The next step up if you don’t feel like you're getting relief with Claritin or Zyrtec, instead of going to like Claritin D where we don't really like the pseudoephedrine, would be using like a saline or a steroid nasal spray like Flonase. Flonase is available over the counter, and as a nasal spray is also incredibly safe,” Alfonso says.

So, if you need to take something for some relief from your allergies, just know Zyrtec should get the job done — and it’ll do it safely.

Studies referenced:

Głowacka, K., & Wiela-Hojeńska, A. (2021). Pseudoephedrine—benefits and risks. International Journal of Molecular Sciences, 22(10), 5146.


Dr. Sarah Ziebarth, M.D., OB-GYN at Methodist Le Bonheur Healthcare

Dr. Clayton Alfonso, M.D., board-certified OB-GYN at Duke Health