Blue Xanax Bars B707 are rectangular cuboid that is 2mg strong and have the inscription "B 707" on one side. Xanax is a benzodiazepine medication that works to enhance the effect of a naturally occurring chemical in the brain that calms and relaxes your body. They are benzos that increase the activity of the neurotransmitter GABA or Gamma-aminobutyric Acid. GABA inhibits nerve transmissions in the central nervous system, which includes the brain and spinal cord. Reduced nerve transmissions result in a less excited state of the body, causing it to relax and feel calm.