Buy Yellow Xanax Online Xanax, the 12th most prescribed medicine in the United States, is a very potent short-acting benzodiazepine drug. It has been popularly used to aid the treatment of anxiety disorders, panic disorders, and also for generalized anxiety disorder(GAD). Xanax slows the chemicals that are unbalanced and increases the number of natural chemicals in the brain, resulting in reduced tension, anxiety, and nervousness. What are these yellow Xanax bars? Pills that are imprinted R039 and have yellow-coated color are known to be Yellow Xanax bars. Although there is no such big difference between a normal Xanax bar and a yellow bar. It’s just the imprinted number and the color that make it different from the normal one. It is supplied by Actavis and it is identified as Alprazolam 2 mg.