anxiety
"I started taking Xanax at age 20 and it was a great medicine. I had such bad panic attacks and just constant anxiety 24/7.  I started out on a low dose and within 15 mins I felt calm and fine. I got from the place of not being able to walk outside or answer the phone to being able to get married, have a job, go on vacations. Anything I wanted to do. I WAS NORMAL.  But now I'm 36 and on the highest dose 4 mg a day and about 4 1/2 years ago my horrible anxiety came back even though I'm taking it.  I can't work, drive or really go anywhere anymore.  So I guess I'd say it works but then you may build up a tolerance and then it won't work. "