Alprazolam, commonly known by the brand name Xanax, is a prescription medication that belongs to a class of drugs called benzodiazepines. It is primarily used to treat anxiety and panic disorders, but may also be prescribed for other conditions such as insomnia and depression. Alprazolam works by enhancing the effects of a neurotransmitter called gamma-aminobutyric acid (GABA), which helps to calm the brain and reduce feelings of anxiety.