Atarax (Generic Hydroxyzine Hydrochloride Tablets) reduces activity in the central nervous system and also acts as an antihistamine that reduces the effects of natural chemical histamine in the body. It is an antihistamine and works by blocking a certain natural substance (histamine) that your body makes during an allergic reaction. Hydroxyzine tablets are used as a sedative to treat anxiety and tension. Hydroxyzine may also be used short-term to treat anxiety or to help you feel sleepy/relaxed before and after surgery. Hydroxyzine is also used to treat allergic skin reactions such as hives or contact dermatitis.