[syncroid]

I used to get them quite often until I figured out what the triggers were. For me the triggers are preservatives in foods. Sodium nitrate, sodium nitrites, MSG is a big one too. Even sulfites in some wines will do it. I will sometimes get them on the first or second day of a vacation. I think that is my bodys way of telling me I shouldn't burn the candle at both ends.
I can always tell when I am getting one. The first sign is the visual scotoma. It feels at first like you have walked into a dark room after being out in the sun or a flash bulb has gone off in your face. (blind spots) Then the kaliedascope in the perifery vision. Cafergot seems to help if you take it at the first sign of visual scotoma. If I don't have any of that I drink a coke or mt. dew with a couple of advil. The visual effects usually last about 30 minutes. Being in a quite dark room helps too. Most of the time I don't get the headache.