Many allergy drugs may be fine to keep taking during pregnancy, but have the discussion so you can have peace of mind. Oral antihistamines, like cetirizine (Zyrtec), chlorpheniramine (Chlor-Trimeton), diphenhydramine (Benadryl), fexofenadine (Allegra), and loratadine (Claritin) seem to be safe.Click to see full answer. Also know, what pregnancy category is loratadine?If a second generation agent has to be used then loratadine or cetirizine should be preferred as they have been widely studied for possible teratogenic effects and have been found to be nonteratogenic till date. Both these agents are pregnancy category B agents. is it safe to take loratadine while breastfeeding? Yes. Studies estimate that a breastfeeding baby whose mother is taking loratadine would get less than 1% of the mother’s dose. This, along with the low levels in milk, makes loratadine one of the preferred antihistamines for use during breastfeeding. Moreover, does loratadine cross the placenta? Cetirizine, desloratadine, fexofenadine, and loratadine are among the second-generation antihistamines. Desloratadine is a major metabolite of loratadine. Therefore, all of the antihistamines have the possibility of crossing the placenta and reaching the fetal blood.Is cetirizine safe during third trimester?Second-generation antihistamines, such as cetirizine (CTZ) and loratadine, are considered safe in pregnancy and are not associated with an increased risk for major congenital malformations (Li et al. 2013. Assessment of antihistamine use in early pregnancy and birth defects.