This is a test that is done to find out whether a person is allergic to a food. The food challenge is done in the Allergy Clinic or in the hospital. Medications are ready to reverse a reaction if it occurs, and the physician and nurse monitor the patient carefully. The challenge starts with a very small amount of the suspected food allergen, and the patient is observed for a period of time. If there is no reaction, a slightly larger amount of the food is given and the patient is again observed for any reaction. The oral challenge proceeds until a full serving of food has been eaten, or until there is an allergic reaction. It is rare for a severe allergic reaction to occur to an oral food challenge, because of the very small initial dose and very gradual increase in dose. Food challenges are done if it is unclear whether a patient is allergic to the food in question, or when a previous food allergy seems to be resolving.