Blue Xanax bars are a brand of Alprazolam, which belongs to the benzodiazepine class of medications. They are most commonly prescribed for managing anxiety disorders, panic disorders, and sometimes insomnia.Each bar typically contains 2 mg of Alprazolam, the highest standard tablet strength. They are rectangular, blue-colored bars, often scored into 4 smaller sections for easier dosing. Scoring allows patients to split the bar into smaller doses if prescribed.