What is a blue Xanax bar? B 7 0 7 Blue Pill, Rectangle and has been identified as Alprazolam 2 mg. Alprazolam is used in the treatment of anxiety; panic disorder and belongs to the drug class benzodiazepines. There is positive evidence of human fetal risk during pregnancy. Alprazolam 2 mg is classified as a Schedule 4 controlled substance under the Controlled Substance Act (CSA).