Zyrtec and Pregnancy
Although Zyrtec (cetirizine) appears to be safe to take during pregnancy, the full risks are not yet known. In animal studies, high doses of the drug did not cause any problems. However, Zyrtec has not been studied adequately in pregnant women. Be sure to let your healthcare provider know if you are taking Zyrtec and pregnancy occurs.
Zyrtec® (cetirizine hydrochloride) is an antihistamine approved to treat allergies and hives. It is available without a prescription. Zyrtec appears to be safe for use during pregnancy, although the full risks are not currently known. The labeling of Zyrtec products contains a warning that pregnant women should consult their healthcare providers before taking the drug.
The U.S. Food and Drug Administration (FDA) uses a category system to classify the possible risks to a fetus when a specific medicine is taken during pregnancy. Pregnancy Category B is given to medicines that have not been studied extensively in pregnant humans but that do not appear to cause harm to the fetus in animal studies. It is also given to medications that cause apparent problems in pregnant animals but have been shown to be safe in human studies.
Zyrtec was given a pregnancy Category B classification because even at high dosages, the drug did not cause any problems when given to pregnant animals. There is no reason to expect that Zyrtec will cause problems during pregnancy. However, the drug has not been adequately studied in pregnant women, so the full risks are not known.
While animal studies did not suggest problems with Zyrtec, these studies could not completely rule out the possibility of problems. Therefore, a pregnancy Category B medicine should be given to a pregnant woman only if her healthcare provider believes that the benefits to the woman outweigh any possible risks to the unborn child.