What is Oral Allergy Syndrome (OAS)?

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People experience hay fever or seasonal allergies when the immune system associates the proteins contained within pollen as a harmful invader. Certain white blood cells then come to the rescue to destroy and eliminate the enemy. The cells also trigger the release of histamine and other chemicals in response to the perceived attack. This defense system causes a variety of symptoms that often include sneezing, runny nose, and itchy and watery eyes.

Oral Allergy Syndrome

Fruits and vegetables also contain proteins, which are similar in structure to pollen proteins. Oral allergy syndrome, or OAS, occurs when the immune system mistakes these proteins with the compounds found in pollen and initiates an attack. When eating certain produce products, someone suffering from oral allergy syndrome OAS experiences itching in the mouth and throat. The throat may tighten or close because of the swelling and irritation that occurs. These people may mistakenly believe that they have a food allergy when in actuality, a cross-reactive event has taken place.

Oral Allergy Syndrome Causes and Diagnosis

Oral allergy syndrome doctors now know that the proteins in specific pollen correlate with the proteins of certain fruits and vegetables. Subsequently, someone having a reaction to ragweed may have a cross-reaction to:

• Bananas
• Cantaloupe
• Honeydew melons
• Watermelons
• Tomatoes
• Chamomile tea
• Dandelions
• Echinacea
• Sunflower seeds
• Zucchini

Birch pollen suffers may react to:

• Almonds
• Apples
• Carrots
• Celery
• Cherries
• Coriander
• Fennel
• Hazelnuts
• Kiwi
• Parsley
• Peaches
• Pears

Someone having a grass pollen allergy may react to:

• Celery
• Fruits in the melon family
• Oranges
• Peaches

Latex allergy sufferers may have a reaction to:

• Avocados
• Chestnuts
• Kiwi
• Papaya

Determining oral allergy syndrome causes and diagnosis begins with a medical history. If a patient has a diagnosis for a particular seasonal allergy, oral allergy syndrome doctors perform a skin-prick test to assess for sensitivity to similar proteins. Oral allergies develop much later than the onset of pollen allergies. Most sufferers are adults over the age of 20.

OAS Treatment

Treatment depends on the severity of symptoms. Research suggests that approximately 2 percent of patients experiencing oral allergy syndrome OAS progress to having life-threatening symptoms. Depending on the patient, physicians may recommend carrying an emergency epinephrine injection.

The simplest means of preventing symptoms involves avoiding the foods that cause an allergic response. If a food is questionable, physicians recommend eating the fruit or vegetable peeled, cooked or canned, which breaks down the proteins into forms not readily recognized by the immune system.

If you have any personal questions about your OAS or are wanting to get tested for Oral Allergy Syndrome, give the allergists here at Asthma & Allergy Associates P.C. a call today! Our friendly staff is here to help you and make your life easier!

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