Oral Allergy Syndrome

Oral allergy syndrome (OAS) is an allergic reaction caused by consuming certain raw fruits, vegetables, and nuts. Symptoms of OAS can range from mild itching and tingling in the mouth to anaphylaxis. The main cause of OAS is cross-reactivity; the proteins in raw fruits, vegetables, and nuts are similar to proteins found in pollens that the individual is allergic to, causing the immune system to overreact. The best way to prevent OAS is to cook the offending fruits and vegetables and to avoid eating raw nuts. Being aware of your allergies and avoiding allergenic foods is an important part of preventing OAS and taking the necessary precautions to treat a reaction if it occurs.