Oral Allergy Syndrome (OAS), also known as pollen-food syndrome, is a condition that causes allergic reactions in individuals who are already sensitized to pollen.

It is a type of food allergy that occurs due to cross-reactivity between certain proteins found in fresh fruits, vegetables, and nuts, and the pollen proteins to which the person is allergic.

Who Gets Oral Allergy Syndrome?

Oral Allergy Syndrome can develop in both children and adults. It is more commonly seen in individuals who have pre-existing hay fever or allergic rhinitis.

People who are allergic to tree pollen, such as birch, oak, or alder, are particularly susceptible to developing OAS. However, it can also occur in individuals who are allergic to grass or ragweed pollen.

What Causes Oral Allergy Syndrome?

The primary cause of Oral Allergy Syndrome is cross-reactivity between certain proteins in fruits, vegetables, and nuts, and the proteins found in pollens.

When individuals with pollen allergies consume these trigger foods, their immune system recognizes the similarity between the proteins and mistakenly identifies them as harmful. This triggers an allergic response, leading to the typical symptoms of OAS.

Common Food Triggers

Several fruits, vegetables, and nuts are known to act as common triggers for Oral Allergy Syndrome. These include:.

Apples
Apricots
Cherries
Plums
Peaches
Pears
Almonds
Hazelnuts
Walnuts

What are the Symptoms of Oral Allergy Syndrome?

The symptoms experienced by individuals with Oral Allergy Syndrome can vary in intensity and duration. The reactions are usually localized to the mouth, throat, and lips, and typically appear immediately or shortly after consuming the trigger food.

Some common symptoms include:.

Itchy or tingling sensation in the mouth
Swelling of the lips, tongue, or throat
Redness and irritation
Watery eyes
Runny or blocked nose
Sneezing
Coughing or wheezing (in rare cases)

Cross-Reactivity Patterns

Oral Allergy Syndrome symptoms can vary depending on the specific pollen-food cross-reactivity pattern. Individuals with birch pollen allergies may experience symptoms when consuming apples, pears, almonds, and carrots.

Those with grass pollen allergies may react to melons, tomatoes, and oranges. Ragweed pollen allergies can cause reactions to bananas, melons, and cucumbers. However, it is important to note that cross-reactivity can differ from person to person.

Managing Oral Allergy Syndrome

While complete avoidance of trigger foods is the only surefire way to prevent OAS symptoms, many individuals find that they can tolerate cooked or processed versions of the trigger foods.

The allergenic proteins that cause the cross-reaction are often destroyed or altered during cooking or processing, reducing the likelihood of an allergic response.

It is advisable for individuals with OAS to consult with an allergist to determine their specific trigger foods and develop an appropriate management plan.

In some cases, allergists may recommend immunotherapy, which involves gradually and safely exposing individuals to small amounts of the allergen to build tolerance and reduce symptoms.

Conclusion

Oral Allergy Syndrome, or pollen-food syndrome, is a condition that affects individuals with pollen allergies. It is characterized by allergic reactions triggered by the consumption of certain fresh fruits, vegetables, and nuts.

The symptoms mainly occur in the mouth, throat, and lips, and can range from mild itching to more severe swelling. Proper management, including avoidance or modification of trigger foods, can help individuals with OAS lead a comfortable and symptom-free life.