Personally it's one of the stronger prescriptions I've used, it helped me sleep when I was anxious before exams or other important deadlines. It usually helped me relax when I took it during the day time. It should be noted that I'm lightweight and have been chemically sensitive in general. Also, I've been very moderate with my usage of any substances (to prevent addiction) and Xanax was no exception. My dosage has rarely been over 1 mg, as even .5 usually suffices in my case. I rarely use it anymore, but I never dosed more than three times in a week in the past.. even during times of my most frequent usage.
Every individual reacts differently to every chemical. You may want to seek out another prescription, but here are some initial questions to ask.
What is your reason for taking Xanax? (ie. anxiety, insomnia, etc.)
What specific dosages are you taking, and how frequently?
Are you taking any other prescriptions, drinking, eating anything unusual?
When was the Xanax prescribed? (any expiration date listed?)