Hello and welcome to e health forum.
From the additional history provided, its seems that the dose of xanax, that helps you is very high.
This could be due to the fact that either you are resistant to xanax or that you have become addicted to it.
In addition the treatment for Panic attacks is SSRIs like fluoxetine. Xanax is given only for short term treatment of panic attacks.
You might consult your psychiatrist and undergo Cognitive-behavioral therapy which might be very helpul for you, as it will - help in:
1. Gaining understanding of and control over distorted views of life stressors or life events.
2. Learning to recognize and replace panic-causing thoughts to decrease the sense of helplessness.
3. Learning stress management and relaxation techniques to help when symptoms occur.
Behavioral treatment appears to have long-lasting benefits.
Regular exercise, adequate sleep, and regularly scheduled meals may help reduce the frequency of the attacks. Reduce or avoid the use of caffeine, some over-the-counter cold medicines, and other stimulants, because they may make symptoms worse.