The general public often considers food allergy to be any type of adverse food reaction. Although there are many types of adverse food reactions, allergists define food allergy specifically as the type of reaction mediated by the allergic antibody, IgE. Only IgE mediated food reactions are potentially life-threatening.
If an individual is truly allergic to a food, that person will not be able to ingest even a small portion of that food item without sustaining a significant allergic reaction. True allergic reactions typically begin within minutes and definitely within two hours of ingesting the food item. Food allergy will almost invariably be manifested by hives in addition to other possible symptoms. Allergy skin or blood test will be able to detect the presence of IgE in virtually all cases.
Food allergy is treated by strict avoidance of even trace amounts of the offending food. In the event of accidental ingestion, an immediate release version of antihistamine (e.g. chewable Benadryl) should be taken immediately. If allergy symptoms develop, proceed towards an emergency room immediately. Take Epi-Pen if symptoms become severe (breathing difficulty or light-headedness).
Non-allergic adverse food reactions include lactose intolerance, protein intolerance, non-specific intolerance and irritable bowel syndrome. These types of reactions are not accompanied by hives.
Authored by Robert Settipane, MD