Readyfeet,
I had an anxiety disorder for about 13 years before I started meditating seriously. I took SSRI medications like Zoloft and Lexapro. As a result of vipassana, the anxiety has essentially
disappeared now and I am completely off of medications. So I'd say vipassana is a very fruitful approach. No matter what the kind of anxiety, the basic principle is the same.
The goal is to identify the feelings of anxiety in the body in as much detail as you can, what and where. Look with a magnifying glass, so to speak at each of these sensations (i.e. vedana). The pattern in the body will be very regular and consistent. Before I started meditating, I never even gave thought to this. All I knew was that it was a general yucky feeling. Once I started meditating and the anxiety recurred, I made those feelings the main object of meditation. I saw that there was a great deal of specificity that I never noticed before--for 13 years! That's because I was too busy trying to distract myself from the symptoms to notice what was going on right under my nose.
Secondly, watch these sensations with as much equanimity as you can muster. In other words, observe without trying to resist, control or interfere with them. Give them complete permission, so to speak, to increase/decrease, move, shift, etc. with no resistance. Shinzen Young says that Suffering = Pain x Resistance. So cut down or eliminate the resistance. The irony of this is that it's not something that's happening
to you. It's something that you are
actively perpetuating, even though you're unaware of it. The most automatic habit is to try to resist and/or avoid unpleasantness. With anxiety, attempts to do this become of epic proportions, dreading the experience and wishing it would go away. So rather than "getting rid of it," all you need to do is not feed into it in the first place. This becomes more and more apparent the more you develop mindfulness of these bodily feelings.
Instead of dreading the experience, take an attitude of investigation & curiosity. Rather than viewing the anxiety as a hassle, welcome it as an opportunity to learn. Every second that you apply mindfulness and equanimity to the experience you are literally rewiring your habitual response to it (i.e. purification of sankharas). This shift in attitude itself is a major turning point since it further diverts you from dreading/resisting the experience. Every single time you make even a little effort to do this, you will get getting better this skill. In the long run, having dealt with the anxiety this way will be a great advantage in furthering your practice. My symptoms don't even seem to occur anymore, but if they did, I wouldn't be concerned. I know what to do.
The other good news about anxiety is that it is a heightened state of attention. Attention is generally a good thing for mindfulness, so it's a matter of re-directing it somewhat and adding equanimity into the mix. Depression, on the other hand, can be more stubborn since depressed people have a hard time arousing concentration. A word of caution though: if you go on a meditation retreat, the anxiety may "return" or "worsen." I put those in quotes because literally it is not worsening or returning, you're just becoming more aware of it on a more subtle level. So it can seem like it has been exacerbated, but actually a retreat is a prime environment and opportunity to work with these sensations on a very subtle level.
If you have any further questions or need help, feel free to contact me. Trust me when I tell you that you can greatly reduce the anxiety and eventually be rid of it.
Incidentally, Buddhaghosa mention of a monk named Sammunjani who had OCD in his commentary on the Dhammapada:
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http://tiny.cc/xvw5e" onclick="window.open(this.href);return false; (see p. 5, XIII "The Monk With a Broom")
