An accurate diagnosis history of food allergy begins with a detailed history of specific symptoms associated with consuming specific foods. A food allergy evaluation should be performed by a board certified allergist with expertise in evaluating and managing food allergies. A diagnosis of food allergy is not made by simply ordering a panel of blood tests, as the results of these tests must be correlated with the patient’s history of allergic reactions to the food(s) in question. In the absence of a correlating, the predictive value of a positive food allergy test is not much better than 50%. A positive allergy test for a food suggests the possibility of an allergic reaction, but does not predict the severity of that reaction nor the amount of food required to trigger it.
Symptoms of a food allergic reaction typically start within a few minutes after eating the allergenic food. Such reactions usually include itching and/or swelling of the mouth, throat and face and may progress to wheezing, difficulty breathing, abdominal cramping, nausea, vomiting and even anaphylactic shock. Severe allergic reactions may be triggered by ingesting tiny amounts of food protein. The most common foods causing more than 85% of allergic reactions include milk, egg, wheat soy, peanut, tree nuts, fish and shellfish.
Read detailed information on food allergy evaluations and the importance of an oral food challenge on our blog.