Oral allergy syndrome (OAS) is also called pollen-food syndrome. It occurs when folks who are allergic to pollen eat raw fruits or veggies that have proteins similar to pollen.
This triggers a response when the food is ingested. The response tends to be limited to the mouth and can include itching, tingling, and a small amount of swelling. The symptoms usually go away a few minutes after the food is swallowed or removed from the mouth.
Some of the most common oral allergies are associated with an allergy to birch, grass and ragweed.
If you have an allergy to birch, you may find that you also have an oral allergy to apple, carrots, peaches, plums, cherries, pears, almonds and hazelnut. If you have an allergy to grasses, you may find that your mouth is itchy after eating tomatoes. And an allergy to ragweed is associated with an oral allergy to melons, zucchini, kiwi and bananas.