I've had food reactions in the past. It's been awhile, but I'm going on a week long trip for school in a couple of weeks, and we're supposed to list medical information, and it made me realize that I don't really know what this is.
The first reaction was when I was in my early teens, maybe 14 or 15. I was at a party and had a canape with salmon on it. Didn't really think anything of it. An hour, maybe two, later I woke up from a nap horribly nauseas. I threw up. The nausea kept getting worse, the waves getting closer together and stronger (kind of like labor). Diahrea started maybe half an hour in. After two hours, when I was dry heaving almost non stop, my parents took me to the hospital and they gave me compazine. They did a blood test and my white cell count was elevated. They didn't really say anything else about it though, just sent me home and told me to drink a lot of water and broth until I was sure my stomach was settled. My mom checked and no one else at the party got sick, so it wasn't food poisoning.
My mom is allergic to seafood, so we kind of assumed it was the same. I'm not a big sea food fan anyway so it didn't bother me to just avoid it. Maybe a year or so later we had fish for dinner, and my mom got fresh water trout for her and myself. About an hour after dinner the same symptoms started The hospital gave me compazine and gave me an IV to combat dehydration. I don't recall if they did a blood test, but once again they didn't really talk about what caused it, just to take it easy. The doctor did say I should probably just avoid fish altogether, which we were already planning, but didn't talk about allergies at all.
The third time, maybe 2 years ago, it happened with buckwheat pancakes, of all things. Buckwheat allergies are rare, from what I've read (in the USA at least) but happen, and that was the only ingredient that I don't consume on a regular or semi-regular basis. Again, they gave compazine and IV fluids and sent me home without much more than that.
I've been sick before and since, and this reaction is different than getting sick from the flu. It has a very specific sequence. But I don't really know what to call it. Is it an allergy or an intolerance? I can avoid fish and buckwheat, but since it happened with buckwheat out of the blue it could in theory happen with other foods (or there could be cross contamination and I get exposed at a restaurant, or something). I've never had respiratory symptoms, and it seems like if you don't have those they don't really want to call it an allergy, but that doesn't seem to be a completely solid rule either.
I'm just confused as to what I should document this as. After all, I'm going to NY, which has a fair amount of sea food (a lot more than NE, where I live), so accidental cross contamination is something that I have to seriously consider.