Xanax, a benzodiazepine, is an oral therapy prescription approved by the FDA( Food and Drug Administration) as a potent antianxiety prescription to treat anxiety disorder, panic disorder, and phobia. It belongs to the benzodiazepine group of drugs that come in both brand versions ( Xanax) and generic versions ( Alprazolam). Primarily, doctors prescribe to mitigate the symptoms of anxiety, stress, and depression. Buy Xanax Online. When you take this drug, it starts its effects within 30 to 40 minutes, takes 1 to 1.5 hours to reach the peak, and lasts in the symptom for up to 6 to 8 hours.