What Is an OAS Allergy?

OAS (Oral Allergy Syndrome) is an allergy to fresh fruits or vegetables caused by a cross-reaction to pollen. The condition can occur at any time but may be worse during the allergy seasons of spring and fall.

The Facts

• When a person with pollen allergies consumes raw fruits or vegetables, his immune system may detect similarities between pollen proteins and food proteins, causing an allergic reaction.

Causes

• A wide variety of foods can induce OAS, depending on the type of seasonal allergy that affects a person. Ragweed allergy is the most common; people who are allergic to ragweed may experience symptoms after eating foods such as melons, bananas, cucumbers, chamomile, Echinacea, sunflower seeds and zucchinis.

Symptoms

• OAS allergy symptoms can include itching and swelling of the mouth, lip, face, tongue and throat. Hives also may appear in the mouth. Symptoms usually occur within minutes of eating the trigger food.

Considerations

• People who experience OAS may also have an allergy to latex.

Seeking Treatment

• Consult an allergist for evaluation and treatment recommendations.