Quick Facts: Oral allergy syndrome (OAS) brings about one more set of symptoms that people with seasonal allergies and asthma may have to put up with come late summer and fall. OAS occurs in about a third of people who have seasonal allergies and involves a cross-reaction between airborne allergens, such as pollen, and proteins in certain foods. It is sometimes called "pollen-food syndrome."
How It Makes You Feel: The primary symptoms of oral allergy syndrome include:
- itchiness of the mouth or throat
- swelling and hives affecting the mouth, face, lips and throat
Although these symptoms are not usually life-threatening, they can degrade your quality of life, especially if you have other allergy and asthma symptoms that are already bothering you. In a few people, OAS symptoms may progress to severe throat swelling and/or a more generalized allergic reaction called anaphylaxis, which can be life-threatening.
Who Is at Risk: OAS occurs in some people who are already sensitive to pollen, especially
ragweed pollen, when they eat fresh fruits and vegetables. Symptoms usually occur right after eating. The foods that are most likely to trigger OAS symptoms in people allergic to ragweed pollen include:
- Bananas
- Cucumbers
- Melons
- Zucchini
- Sunflower seeds
- Chamomile tea
- Echinacea, an herb sometimes used to treat allergies
There can also be a cross-sensitivity between birch tree pollen allergy and OAS. Foods most likely to cause oral allergy symptoms in those people include:
- Peaches
- Apples
- Pears
- Cherries
- Carrots
- Hazelnuts
- Kiwi fruit
- Almonds
When It Occurs: Oral allergy syndrome is largely a seasonal disorder, since it occurs in conjunction with seasonal allergy triggers, such as ragweed and birch tree pollen. Tree pollen levels are generally highest in the spring and early summer, depending on where you live, when trees are blooming.
However, ragweed pollen allergy is by far the more common cause of OAS, as 36 million people are estimated to suffer from ragweed allergy. Ragweed pollen levels are highest in the fall, but ragweed begins blooming around August 15th each year.
What You Can Do: As with other allergy and
asthma triggers, the best policy is to avoid the triggers as much as possible. To avoid ragweed pollen, stay indoors as much as you can on hot, dry, windy days when pollen levels are high, especially during the middle part of the day. If you must go outside, try to do so in the early morning, when pollen levels are lowest. Also, if you notice any symptoms of OAS, avoid the foods listed above as much as possible. Cooking the foods often reduces or prevents reactions, so you can try that, too.
