Xanax is a benzodiazepine. It is assumed that alprazolam functions by improving the activity of particular neurotransmitters in the brain. Xanax is used to treat anxiety conditions and anxiety driven by depression. Xanax is also used to treat panic disorders with or without a fear of places and problems that might cause helplessness, panic or embarrassment (agoraphobia). It is harmful to purchase Xanax online or beyond the United States. The sale and issuance of medicines outside the U.S. do not comply with the Food and Drug Administration (FDA) safe-use rules. These medications may have harmful ingredients, or may not be distributed by a certified apothecary.