I deal with severe, episodic nausea (probably not related to anxiety, but still...). When I was on zyprexa it went away for years. It turns out that zyprexa has anti-nausea properties (probably wants to ensure that you keep down the extra 60,000 calories you'll eat a day on it).

Right now I take omeprazole (prilosec) for acid reflux, and somehow (I don't think this is it's intended effect) it keeps the nausea under control. Not sure how, but every time I skip a few doses, the nausea comes back. So you could ask your MD for that. You can even get prilosec over the counter, but it comes in low doses. I'm on 40 mg, which is prescription strength.