Anxiety often accompanies depression and sometimes improves with use of antidepressants. Perhaps your doctor has observed symptoms of depression and/or heard you report them. In any event, like Paxiled I think you should discuss these issues with your psychiatrist to determine his precise reasons for wanting to prescribe it for you. If you don't have symptoms of depression, taking an antidepressant may be unnecessary, especially if occasional use of Xanax controls your anxiety. You would have to take an antidepressant all the time. Discontinuing use of antidepressants may be difficult and cause adverse symptoms in some cases, much like stopping regular use of benzodiazepines. I don't believe anyone should insist that you take an antidepressant simply because you occasionally use Xanax for anxiety alone. Based on what you've said, in my view it's probably not a better option for you. If you were to decide not to take an antidepressant, you and your doctor could then monitor your symptoms to ensure your use of Xanax as needed is sufficient.
I agree with Paxiled. I was diagnosed with an anxiety disorder as well and tried several antidepressants that did not work and made it worse. I finally came to realize I'm not depressed I just have anxiety attacks. I can feel an attack coming on and have practiced on controlling them. Discussed what I wanted with my doctor and she prescribed Ativan, which I haven't taken in almost two yrs. But I only took it when I couldn't control the attack. I also haven't hyperventilated and passed out from an attack since I learned to control the attacks and avoid triggers that cause them.
If you're feeling good, you don't need a drug. If you're still anxious but feel great without the drugs, and they do change our brains, have you tried to do this with therapy and lifestyle changes rather than with medication? If the anxiety is still overwhelming your life and therapy has never worked, then you probably do need to find a different medication. It all depends on how your life is going, and if it's going fine, you don't need medication.