 [ Symptoms ] can i take antihistamines an otc drug when pregnant [ Disease ] antihistamines are used to treat allergy symptoms we have two generations of antihistamines first generation antihistamines like chlorpheniramine dimenhydrinate diphenhydramine doxylamine are considered safe to use during pregnancy these medications have sedative effect cause sleepiness the newer non sedating antihistamines like cetirizine desloratadine fexofenadine and loratadine are best avoided in pregnancy as we have no strong evidence confirming its safety in pregnancy hope this helps consult a general medicine physician online for further queries   > <link>