Hm, I'm not that well read on anxiety disorders, but in my particular case it seems to be biological -- a chemical disbalance, one aspect of which was related to the acidity of the foods I ate. A change in diet helped alleviate this problem and an addition of omega 3&6 fatty acids in my daily intake seems to be holding them at bay entirely, though they begin to return if I deviate from my current regimen.
Perhaps you could consider a change in your diet to reduce the risk as well? It's the least invasive method of handling the problem. A consultation with a dietician may be in order though -- a person's unique metabolism is a finicky thing. In my case it was mostly "self medication" thanks to advice I've read on the net (regarding omega3/6) and general diet advice.from my mother.