Short description Overview   Hydroxyzine is a sedative used to treat tension and anxiety. The drug works by reducing the activities in the central nervous system. It also works as an antihistamine by decreasing the volume of histamine in the body. Histamine can cause symptoms of runny nose, sneezing, and hives on the skin.   When combined with other medications, Hydroxyzine is given for anesthesia. It is also used to control vomiting and nausea. It can also be prescribed to treat allergic reactions on the skin such as contact dermatitis and hives.