He's not the only one who lists Xanax (generic alprazolam) as his or her favorite. The most popular post by far on Shrink Rap is "Why Docs Don't Like Xanax (Some of Us)."
But some people take a good thing too far. Dinah described a New York Times piece last week about a Kentucky clinic that has been so overwhelmed by patients requesting and abusing this very addictive anxiety medication that they have decided to completely stop prescribing it. They do plan to appropriately taper people off of it or switch to a less problematic medication. Because of Xanax's short half-life, it gets into the brain quickly, giving a reinforcing if calming rush. Unfortunately, it's level also falls rapidly. This is fine for the occasional use, but regular daily use of significant doses can lead to severe withdrawal, seizures, and delirium when it is suddenly stopped, which happens if one uses it up prematurely and cannot get an early refill. (Read the above Shrink Rap article for more about this.)