If you want to buy Xanax 0.5mg, then you must understand that Xanax is a drug which is the name by which Alprazolam is popularly known in the market or online, and is a benzodiazepine, which means that it depresses the central nervous system (CNS). When you decide to buy Xanax 0.5mg online and from an online pharmacy that can provide you with a prescription, you get to know that the drug is mainly prescribed to treat anxiety and panic disorder. The prescription will also tell you a lot about medicine, like side effects and withdrawal symptoms.