'but it went away after extensive tests by AVM Cook'
Nope. An allergy is an abnormal learned response of the im,mune system. Once you have an allergy it doesnt go away (unless you are desensitised - a rare and far from simple procedure).
A significant proportion of patients who tell me they are allergic arent. Period. There is also controversy as to whether allergy is increasing in frequency or occurance or frequency of diagnosis.