sweetsleep28 41 Posts Specializes in LTC, Rehab. Has 3 years experience. Aug 18, 2011 Yes, people can develop an allergic/anaphylactic reaction from merely being in the presence of substances that trigger an allergy. My husband is super sensitive to most powdered soaps. He can become itchy and feel agitated just walking down the detergent aisle in the store. I can tell within minutes of walking into a house I've never been to before if a cat resides there. If this can happen with non-food items, why wouldn't it also take place with edibles? In fact, cooking a substance would increase the likelihood of releasing molecular amounts into the air.Because of this, people with severe peanut reactions sometimes have to notify airlines when they are traveling so the flight can be made peanut free. It isn't enough for just the allergy-sufferer to avoid the food. No one around them can indulge either.But in the case you mentioned, it sounds like this girl is using dramatics to avoid future mushroom contact or she really believes her own hype. In either case, it might be easier for your brother to find a new girlfriend than for you guys to change her mind. BTW, I always thought that Shenanigans would be a great name for a bar.I learned something new today. If I would have thought about it a little longer I would have realized that myself. lol. thank you. no sarcasm intended at all. She tends to have a flair for the dramatic is a drama major. :) Without literally assessing her I would presume she was being dramatic. I also forgot to to mention that she was fine while she was in the car with me bringing that mushroom pizza home. oh well chalk it up to the exagerrative tendies of a 20 year old.