Alprazolam, sold under the brand name Xanax, among others, is a fast-acting, potent tranquilizer of medium duration in the triazolobenzodiazepine (TBZD) class, which are benzodiazepines (BZDs) fused with a triazole ring. It is most commonly used in management of anxiety disorders, specifically panic disorder or generalized anxiety disorder (GAD). Other uses include the treatment of chemotherapy-induced nausea, together with other treatments. GAD improvement occurs generally within a week. Alprazolam is generally taken by mouth.

Common side effects include sleepiness, depression, headaches, feeling tired, dry mouth, and memory problems. Some of the sedation and tiredness may improve within a few days. Withdrawal or rebound symptoms may occur if use is suddenly decreased; gradually decreasing the dose over weeks or months may be required. Alprazolam increases all-cause mortality. Alprazolam, like other benzodiazepines, acts through the GABA_A receptor.

Alprazolam was invented by Jackson Hester at the Upjohn Company and patented in 1971 and approved for medical use in the United States in 1981. Alprazolam is a Schedule IV controlled substance and is a common drug of abuse. It is available as a generic medication. In 2020, it was the 37th most-commonly-prescribed medication in the United States, with more than 16 million prescriptions.