Benadryl is a brand name for a number of different medications sold by Johnson & Johnson to relieve allergies and coughs. It usually contains antihistamine diphenhydramine. In the United Kingdom, it contains either the antihistamine acrivastine or the long-acting antihistamine cetirizine. Benadryl products are sold in Australia and New Zealand as a cough medicine and do not contain any antihistamine.^[1][2]