Aug. 31 (HealthDay News) -- Up to one-third of people with seasonal allergies may suffer oral allergy syndrome (OAS), which results from a cross-reactivity between seasonal airborne pollen proteins from weeds, grass and trees and similar proteins in some fresh fruits and vegetables.

Common symptoms of OAS -- also known as pollen-food syndrome -- include: itchiness, tingling or swelling of the mouth, tongue and throat immediately after eating fresh fruits, vegetables and certain kinds of other foods, according to the American Academy of Allergy, Asthma & Immunology (AAAAI).

In some cases, people may suffer severe throat swelling or even a systemic reaction.

People with ragweed pollen allergies might experience symptoms if they eat foods such as bananas, cucumbers, melons, zucchini, sunflower seeds, chamomile tea and Echinacea.

People with birch tree pollen allergies may experience OAS symptoms if they eat food such as peaches, apples, pears, cherries, carrots, hazelnuts, kiwi fruit or almonds.

In most cases, cooking these foods will reduce or prevent an allergic reaction.

The AAAAI recommends people consult an allergist/immunologist if they:

• experience itchy mouth from raw fruits or vegetables;
• have limited their diet based upon perceived adverse reactions to food or additives;
• have prolonged or severe symptoms of rhinitis;
• have nasal polyps;
• have co-existing conditions such as asthma or recurrent sinusitis;
• have symptoms that interfere with their quality of life and/or ability to function;
• have found medications to be ineffective or have had adverse reactions to medications;
• are a child with allergic rhinitis. Immunotherapy may prevent the development of asthma.

SOURCE: American Academy of Allergy, Asthma & Immunology. news release, August 2007