A: It could be a mild allergy. Oral allergy syndrome is common and often found in people who suffer from hay fever. These people are actually allergic to outdoor pollens. For instance, if you’re allergic to ragweed, carrots and celery can give you problems. If you’re allergic to birch, a tree pollen, you may have trouble with food such as apples.
Proteins in some raw produce and nuts are very similar to these outdoor pollens. Symptoms don’t last long once the food is swallowed and treatment is not usually required.
This is only true for raw foods. Once the food has been cooked, the protein breaks down and no longer causes symptoms for most.
If cooking doesn’t take care of the itching or tingling, you may have may be a more serious food allergy. See an allergist if your symptoms are more severe or spread beyond your mouth.
— Allergist Sandra Hong, MD