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Dandelion Fields

Oral Allergy Syndrome

Oral allergy syndrome (OAS) is a condition where certain fruits, vegetables, or nuts trigger allergic reactions in individuals who are already allergic to pollen. It's also known as pollen-food syndrome. OAS occurs due to similarities between proteins in certain fresh fruits, vegetables, or nuts and proteins found in specific pollens. When a person with pollen allergies consumes these foods, their immune system may mistake the food proteins for pollen proteins, leading to mild allergic reactions.

Some common FAQs about OAS include:

  1. Symptoms: OAS typically causes itching or tingling in the mouth, lips, throat, or ears immediately after consuming triggering foods. In some cases, it may cause mild swelling or hives around the mouth. Symptoms usually resolve quickly and are localized to the mouth area.

  2. Trigger Foods: The specific foods that trigger OAS can vary based on the type of pollen a person is allergic to. For instance, those allergic to birch pollen might experience reactions to apples, cherries, or almonds, while those allergic to ragweed might react to bananas, melons, or zucchinis.

  3. Cooking and Processing: Cooking or processing the triggering foods can often break down the proteins that cause OAS reactions. Therefore, some individuals might tolerate these foods when cooked as opposed to eating them fresh.

  4. Cross-Reactivity: OAS is linked to cross-reactivity between certain pollens and proteins in foods. This means that if someone is allergic to a specific pollen, they might also react to certain foods containing similar proteins, but it doesn't mean they'll react to all foods with similar proteins.

  5. Management: Managing OAS involves avoiding trigger foods, especially when they are raw. Allergy testing can help identify specific triggers, and an allergist can guide safe food choices and potential cross-reactivity.


Individuals with OAS need to be aware of their triggers, manage their diets accordingly, and seek guidance from a board-certified allergist, for personalized advice and management strategies. 

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