does unisom help with allergies does unisom have an antihistamine in it is the active ingredient in unisom an antihistamine does benadryl and unisom have the same ingredients is there benadryl in unisom is unisom an effective antihistamine is unisom sleeptabs an antihistamine is unisom an antihistamine is unisom safer than benadryl is unisom doxylamine an antihistamine