I ate boiled eggs and broke out into hives. Happened to me at age 12 (pretty severely) and then again age 41 (mildly). But I eat scrambled eggs every day. I also have OAS (oral allergy syndrome) which makes my throat, ears, and lips itch when I eat peanuts, raisins, celery, figs. However I can tolerate Skippy peanut butter or Reese’s peanut butter cups. What gives? This isn’t “changing the consitition of the element” (e.g. allergic to sesame not sesame oil)… or is it?
Cooking methods can certainly affect allergenicity. When you’re allergic to a food, you’re almost always allergic to a protein found in that food. When you cook food at a high enough temperature, you denature some of the proteins in it, changing the shape of the protein molecules.
Until today, I had the idea that cooking would always reduce the allergic reaction (though not typically to zero), on the assumption that denatured proteins would be less allergenic. It’s actually more complicated than I’d imagined. For example, in peanuts, boiling reduces the allergic reaction relative to dry roasting even though dry roasting uses higher temperatures (which would normally be expected to produce more denaturation). Effects of cooking methods on peanut allergenicity - PubMed
I can’t say what’s going on in your case, but I’m curious. When you say “boiled eggs” what do you mean exactly? Soft boiled, hard boiled, poached? Runny yolk or set? And how thoroughly cooked are your scrambled eggs?
As stated maybe cooking changes the allergens. A boiled egg may not get up to the same temperature as scrambled eggs. The peanuts in peanut butter or the candy probably was “cooked” or pasteurized.
I mentioned in a previous post how with a certain medicine I was on if I ate raw tomatoes while taking it I would break out in hives. Cooked tomatoes (ketchup, spaghetti sauce, pizza, chili), no issues.
I have something like that with cucumbers. If I eat even a single slice of raw cucumber, I’m in for what feels like hours of burping afterwards. OTOH, I’ve never been disturbed by any kind of pickled cucumber. Even the quicky “slosh sliced cucumbers with half ‘n’ half water/vinegar for 20 minutes before dinner” my mom used to make.
With the change happening that fast, I figure it must be some chemical change, probably due to the acidity of the vinegar.
I wonder if it has to do with breathing the allergen instead of eating it? Dry whole peanuts may give off some dust, and perhaps poaching an egg in boiling water gives off more egg fumes in the steam than scrambled.
Thanks - by boiled I mean “hard boiled”, and the scrambled eggs are pretty thoroughly cooked - nothing glistening 
Not sure … but I can be around that stuff and even handle peanuts. Just can’t let it pass the lips.
WAG: Could it be something in the shells you’re reacting to? Scrambled eggs, unlike boiled eggs, are removed from the shells before being cooked.
I never liked peanut butter, so not sure there, but I know peanut oil is no problem for me, while dry roasted peanuts and peanut sauces are. I used to eat snickers with no problem but I presume that’s more the low amount of allergen in a single bar rather than chemistry.
From memory (no cite, sorry) there is a range of egg proteins that you can be allergic to, some of which are specific to the white, and some specific to the yolk. It occurs to me that, the yolk being on the inside and all, it’s not going to be exposed to as much cooking as the white if you boil an egg (unlike scrambling). So that could possibly be a factor.
j
I react to uncooked nuts and fruit skins, but cooked they are fine.
Some recipes are also very specific in needing only the whites or only the yolks. Pure egg whites, used in lot of baked goods and confectionaries, that are contaminated with even the tiniest bit of yolk won’t whip up into a stable foam. So there’s foods which “contain eggs” that may have absolutely no yolk in them at all and that can definitely affect the allergens.
I remembered where I read about how you could be allergic to specific proteins from the white or the yolk. A link in this post:
Link:
Both egg yolks and egg whites contain proteins that can cause allergies, but allergy to egg whites is most common.
j