Anyone at any age can develop a peanut allergy or any other food allergy. It sounds like she has a peanut allergy...do NOT let her eat any peanuts or products with peanuts in it. You need to have an epi-pen for her and get her to allergist for allergy tests.
or treenuts of any kind because they are usually processed with peanuts. Many foods are processed in a facility that processes peanuts/treenuts. These are potentially life-threatening foods even though they do not contain peanuts in their ingredient list and the companies clean their equipment. This cannot wait. Any reaction can be anaphylactic and you will have minutes to administer the epipen before she could die. Each reaction is said to be worse and no one can gauge how long it will take for her to go into full anaphylaxis or how long it will take emergency medical assistance to get to you --and if they will be licensed to use epinepherine. If the allergist will not let you in immediately, I would take her to the emergency room. They can draw her blood for the allergy test and rx an epipen just in case.
I developed allergy to peanuts at age 28-29. Had peanut butter for years with few problems. My allergy does not show up in testing. But more than likely, if it was within minutes, it was definitely an allergic reaction.
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