"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&#039;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&#039;m taking it.  i can&#039;t work, drive or really go anywhere anymore.  so i guess i&#039;d say it works but then you may build up a tolerance and then it won&#039;t work. "