Tavist Allergy or generic Clemastine is an antihistamine you can purchase without a prescription for treating the symptoms of the common cold, hay fever, and other allergies. These symptoms can include itchy, watery eyes/nose/ throat/ or skin, cough, rash, or sneezing and interfere with being able to rest. By blocking histamine that is produced as a response to an allergic reaction and acetylcholine, Tavist Allergy will help to dry up watery eyes and a runny nose so you can breathe easier. The generic alternative is not manufactured by the company that makes the brand product.