Can’t enjoy that apple, peach, or cherry? Many people with a condition called Oral Allergy Syndrome (OAS) can experience an itchy mouth/throat, mouth swelling, and rarely throat closing off when eating certain fruits, vegetables, or nuts. OAS is a type of food allergy that develops in adults with seasonal pollen allergies.
When a person has seasonal allergies to some pollens in the air, such as birch, ragweed, mugwort, or grass, they develop antibodies for this pollen. This plant pollen is genetically similar to certain fruits, vegetables, or nuts that the person may eat.
The allergic reactions people with OAS experience are generally mild, and if bothersome enough, do respond to antihistamines like Benadryl or Allegra. Rarely the symptoms can be severe, even life-threatening, and require an EpiPen to reverse the swelling. When these reactions occur, the person often thinks they are allergic to the food they ate, and sometimes this is the case. But usually, the allergy testing done for the suspected fruit/vegetables comes back negative. Even though there is a negative test result, the antibodies to the pollen are cross-reacting with other structurally similar proteins in the food and then triggering the swelling/itching reaction.
Avoidance of the fruit/vegetable/nut is usually the only treatment. Sometimes, if the reaction is mild, taking an antihistamine medicine before eating can help. Allergy shots or allergy drops under the tongue, known as immunotherapy, can also work. With immunotherapy, the patient receives small doses of the pollen that causes their allergy. The low doses help train their immune system to tolerate the pollen without getting allergy symptoms. This tolerance carries over to the food the person reacted to in the past so that they can eat that food without getting throat/mouth swelling. Then you can enjoy that apple, peach, or cherry.
If you are interested in getting allergy testing, beginning immunotherapy, or would like to discuss your allergy symptoms more with a physician, please call our Canyon View Family Medicine office in Spanish Fork at 801-798-7301, and schedule an appointment with Dr. David Beckstead.
Nowak-Wegrzyn A. Clinical manifestations and diagnosis of oral allergy syndrome (pollen-food allergy syndrome). UpToDate. Accessed on 3/31/20 from Clinical manifestations and diagnosis of oral allergy syndrome (pollen-food allergy syndrome)
David Beckstead, MD
Canyon View Family Medicine