Pollen Allergy and Food Reactions Can They Be Related?

By Shaz Siddiqi, MD

Allergy & Asthma Care Centers

. http://www.myallergycare.com/

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Pollen Allergy and Food Reactions Can They Be Related?

If you suffer fromseasonal hay feverand you've ever experienced an itchy mouth or scratchy throat after eating certain raw fruits, vegetables, peanuts and/or tree nuts, you may have special condition known as oral allergy syndrome syndrome.

Oral allergy syndrome (OAS), also known as pollen-food syndrome, is caused by cross-reacting allergens found in both pollen and raw fruits, vegetables, or some nuts. Since pollen and these foods are both plant derived, they share some common proteins in nature. The immune system recognizes the pollen and similar proteins in the food and directs an allergic response to it. People affected by oral allergy syndrome can usually eat the same fruits or vegetables in cooked form because the proteins are distorted during the heating process, so that the immune system no longer recognizes the food.

OAS typically does not appear in young children; the onset is more common in older children, teens, and young adults who have been eating the fruits or vegetables in question for years without any problems. Those with oral allergy syndrome typically have allergy to birch, ragweed, or grass pollens.

Although not everyone with a pollen allergy experiences oral allergy syndrome when eating the following foods, they are commonly associated with these allergens

Birch pollen apple, almond, carrot, celery, cherry, hazelnut, kiwi, peach, pear, plum

Grass pollen celery, melons, oranges, peaches, tomato

Ragweed pollen banana, cucumber, melons, sunflower seeds, zucchini

Symptoms of OAS include itchy mouth, scratchy throat, or swelling of the lips, mouth, tongue, and throat. Itchy ears are sometimes reported. The symptoms are usually confined to one area and do not normally progress beyond the mouth and throat. Because the symptoms usually subside quickly once the fresh fruit or raw vegetable is swallowed or removed from the mouth, treatment is not usually necessary. It rarely if ever progresses to a serious allergic reaction. Diagnosis of oral allergy syndromeis reached after taking a patient's clinical history and, in some cases, conducting skin prick tests and oral food challenges with raw fruit or vegetables.

If you or your child experience a reaction beyond the mouth area after eating a fresh fruit or raw vegetables, or experience considerable throat swelling, that food could be considered a risk foranaphylaxis. This is a serious allergic reaction that is rapid in onset and may be life-threatening. Only a board certified allergist should be consulted to determine which type of reaction is taking place.

In most cases OAS does not require medical treatment. It is best to avoid the offending foods. Often just peeling or cooking the food will reduce the effects. At times, an antihistamine can effectively relieve the symptoms. In adults and children with severe recurrent OAS, immunotherapy(allergy shots) to the pollen have been useful.

Adapted from the ACAAI