**WHAT IS y 21 xanax? If you want to buy y 21 xanax, then you must understand that Xanax is a drug which is the name by which Alprazolam is popularly known in the market or online. Whenever you decide to buy y 21 xanax online, make sure that you buy it from an online pharmacy that can provide you with a prescription along with the prescription drug. The prescription will not only help you in the intake but will also tell you a lot about the medicine, including its side effects and withdrawal symptoms.