From the Guidelines
Yes, oral allergy syndrome (OAS) symptoms can potentially worsen if triggering foods are continually consumed. OAS, also called pollen food allergy syndrome, typically causes mild symptoms like itching or tingling in the mouth when eating certain raw fruits, vegetables, or nuts that contain proteins similar to pollen allergens 1. While most cases remain mild and limited to the mouth area, repeated exposure to trigger foods can sometimes lead to increased sensitivity and more severe reactions in some individuals.
Key Considerations
- The progression risk varies by individual, with factors like the specific food allergen, amount consumed, and your overall allergy profile influencing outcomes 1.
- In rare cases, symptoms may progress beyond the mouth to include swelling of the lips, tongue, and throat, or even systemic reactions.
- If you experience OAS symptoms, consider avoiding or cooking the triggering foods (which often breaks down the allergenic proteins), taking antihistamines before consumption if reactions are mild, and consulting with an allergist for proper diagnosis and management 1.
Management and Prevention
- For milder forms of allergic reactions, such as flushing, urticaria, isolated mild angioedema, or symptoms of OAS, treatment with H1 and H2 antihistamine medications is recommended 1.
- Ongoing observation and monitoring are warranted to ensure a lack of progression to more significant symptoms of anaphylaxis.
- If progression or increased severity is noted, epinephrine should be administered immediately 1.
From the Research
Oral Allergy Syndrome Progression
- Oral allergy syndrome (OAS) is a condition characterized by itchy mouth symptoms, typically triggered by consuming fresh fruits, vegetables, and nuts 2, 3.
- The symptoms of OAS may progress to systemic symptoms outside the gastrointestinal tract in 8.7% of patients and anaphylactic shock in 1.7% of patients 4.
- Continual consumption of triggering foods may exacerbate the condition, and patients with OAS should be advised to avoid or thermally process these foods to prevent reactions 2, 3.
Risk Factors for Progression
- Female patients with seasonal allergic rhinitis are more likely to develop OAS than male patients 5.
- Patients with asthma, nasal itching, and higher symptom scores are also at increased risk of developing OAS 5.
- The adoption of vegan lifestyles, increased consumption of fruits and vegetables, and use of plant foods in nutritional supplements may contribute to the exacerbation of OAS symptoms 6.
Anaphylaxis Risk
- Patients with OAS are at risk of anaphylaxis, particularly when consuming concentrated or unusual forms of plant food allergens such as smoothies, juices, and nutritional supplements 6.
- Proper advice and education on the dangers of these allergens are essential for patients with OAS to prevent severe reactions 6.