I feel so guilty! My DS 5 was diagnosed with a life-threatening peanut allergy when he was 18 months (skin test positive and one ananphylactic reaction). Fast forward to today (here's the guilty part). DS ate quite a bit of candy today and I checked the candy beforehand. One peanut butter cup in a pumpkin wrapper (no brand on the wrapper but an ingredient list at the back that I obviously missed) was still in the bag and my son ate 1/4 of the peanut butter cup!!! Immediately I gave him Benadryl and waited with his epipen in hand (did not give it). Nothing happened! After 30 minutes he became anxious because I was so worried and complained of abdominal pain. He threw up 45 minutes after ingesting the peanut butter cup. Then he was fine. This happened more than 9 hours ago and he is sleeping soundly. I have been checking up on him every 5 minutes since he went to bed. I'm still feeling nervous but the doctor tells me that after more than 8 hours, nothing will happen. We will schedule another allergy test! Still I feel extremely guilty for not finding that peanut butter cup! After 3 1/2 years of peanut allergy and no accidents! Thanks for letting me share the emotions of the day!!!!
The vomiting sounds more like an intolerance than an allergy since its more of a digestive response than an immune response. DD has tested positive for egg allergies, although she can handle them in small quantities and in certain forms, so I'm not really sure what it is.
I'm hoping she's outgrowing it, whatever it is.
!) It is also possible, though not likely with any nuts, that she has outgrown or is outgrowing the allergy. Vomiting and stomach pain can be signs of both allergic reaction and intolerance, so that's not a good way to judge. 
) but I wouldn't take it as a sign that he is no longer allergic at all. From what I have heard from the allergists, your body's reaction can change over time, either to lessen or to get worse ... hence the epi pens even though we've rarely had a reaction beyond the hives & never a respiritory one. But one more exposure might just tip him over the edge.
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