Cross-Reactive Food Allergies

If you have a life-threatening reaction to a certain food, your healthcare provider will show you how to avoid similar foods that might trigger this reaction. For example, if you have a history of allergy to shrimp, allergy testing will usually show that you are not only allergic to shrimp but also to crab, lobster, and crayfish. This is called “cross-reactivity.”
Another interesting example of cross-reactivity occurs in people who are highly sensitive to ragweed. During ragweed pollen season, they sometimes find that when they try to eat melons, particularly cantaloupe, they experience itching in their mouths and simply cannot eat the melon. Similarly, people who have severe birch pollen allergy also may react to apple peels. This is called the “oral allergy syndrome.”