A drug called Alprazolam which belongs to a group of drugs known as benzodiazepines is sold under the brand name called Xanax. It affects the brain by generating a calm effect on the basis of which, the body and brain respond to the anxiety in a different manner. Xanax is prescribed by doctors to treat patients with anxiety and panic disorders. It enhances a specific natural chemical that is present in the body known as Gamma-Amino butyric Acid (GABA). Xanax bars are also used for treatments of nausea induced by chemotherapy.