Xanax 1mg is a prescription-strength tablet that contains 1 milligram of alprazolam, a fast-acting benzodiazepine medication commonly used to treat anxiety disorders, panic attacks, and short-term symptoms of anxiety. Alprazolam, the active ingredient in Xanax, works by enhancing the activity of GABA (gamma-aminobutyric acid) — a calming chemical in the brain — to help reduce nervous tension, restlessness, and excessive fear.