Introduction
An oral food challenge (OFC) is a medical in office procedure in which a food is eaten at intervals with increased doses, under close medical supervision. In many cases, the skin, and/or blood allergy tests cannot conclusively determine that a person is truly food allergic. The OFC is a more definitive test, because it will show whether a person is truly allergic or not.
Benefits
There are multiple benefits provided by an OFC regardless of whether the challenge is positive or negative. If the challenge is negative, the diet can be expanded to include more foods. In the case of peanut allergy, studies show that up to 80% of future peanut allergy can be prevented in high-risk patients if peanut is kept in the diet in sufficient amounts. The patient, and family, will also have less anxiety if the food allergy has been outgrown.If the challenge is positive, the patient and family will learn more about individual symptoms, the reaction severity, the reaction threshold (how much allergen was ingested before the reaction was triggered), and what treatment of a food allergic reaction looks like. In some cases, patients may have a high reaction threshold. This information can be beneficial as it may lessen anxiety concerning small, accidental ingestions/cross-contamination.
Preparation for an OFC
There are several things that you’ll need to do to be prepared for your oral food challenge. You should be off most antihistamines for at least a week. Other medications, including asthma medications, can be continued. In most cases, you will be asked to provide the food. If you are coming in for a peanut challenge, we suggest that you will bring creamy peanut butter. If you are coming in for a baked egg, and/or baked milk muffin challenge, you should have been provided with appropriate baked milk muffin, and/or baked egg muffin recipes. your allergist will make sure that any comorbid conditions such as atopic dermatitis and asthma are well-controlled before proceeding with the challenge. Please do not eat a full meal before coming for the challenge and refrain from eating other foods during the challenge unless approved by your allergist. It would also be helpful to bring in some type of entertainment, such as toys, books, electronics, etc. The challenge may last for 2-3 hours.
