Hi! welcome to HCM! The allergens in food are responsible for inciting an allergic reaction. They are proteins that usually resist the heat of cooking, the acid in the stomach, and the intestinal digestive enzymes. As a result, the allergens survive to cross the gastrointestinal lining, enter the bloodstream, causing allergic reactions throughout the body. The mechanism of food allergy involves the immune system and heredity. Avoiding the offending allergen in the diet is the primary treatment of food allergy. Once a food to which the patient is sensitive has been identified, the food must be removed from the diet. Several medications are available for treating the symptoms of food allergy. antihistamines can relieve gastrointestinal symptoms, hives, sneezing, and a runny nose but the medications are taken after a person inadvertently has ingested a food to which he is allergic. They are not effective, however, in preventing an allergic reaction when taken prior to eating the food. In fact, no medication in any form is available to reliably prevent an allergic reaction to a certain food before eating that food. hope this helps! Take care!