Treatment of Oral Allergy Syndrome from Kiwi
For mild oral allergy syndrome (OAS) symptoms from kiwi, treat with H1 and H2 antihistamines while monitoring closely for progression to more severe symptoms. 1
Acute Management
Mild OAS Symptoms
- Administer H1 antihistamines (e.g., diphenhydramine 1-2 mg/kg per dose, maximum 50 mg) for isolated oral symptoms such as tingling, itching of lips, tongue, or throat 1
- Add H2 antihistamines (e.g., ranitidine) for enhanced symptom control 1
- Maintain close observation during and after antihistamine administration to detect any progression to systemic symptoms 1
Critical Escalation Criteria
- Immediately administer intramuscular epinephrine (0.01 mg/kg of 1:1,000 solution, maximum 0.5 mg in anterolateral thigh) if any of the following develop: 1
- Respiratory symptoms (dyspnea, wheezing, throat tightness)
- Cardiovascular symptoms (hypotension, dizziness)
- Gastrointestinal symptoms beyond the oral cavity (nausea, vomiting, abdominal pain)
- Diffuse urticaria or angioedema
- Any progression of symptoms despite antihistamine treatment
Common pitfall: Relying solely on antihistamines when symptoms progress is the most common reason for delayed epinephrine administration and may place patients at significantly increased risk for life-threatening reactions 1
Long-Term Management
Allergen Avoidance
- Strict avoidance of kiwifruit is the cornerstone of management 1
- Evaluate for cross-reactivity with birch pollen, latex, and other fruits (particularly those containing profilin or lipid transfer proteins) 2, 3
- Kiwi allergens Act d 1 and Act d 2 are ripening-related and most abundant in fully ripe fruit 2
Emergency Preparedness
- Prescribe epinephrine auto-injector for all patients with kiwi allergy, even those with isolated OAS, due to risk of progression 1
- 0.15 mg device for patients 10-25 kg
- 0.3 mg device for patients >25 kg 1
- Provide comprehensive education on: 1
- Recognition of anaphylaxis symptoms
- Proper epinephrine auto-injector technique
- When to use epinephrine (at first sign of systemic symptoms)
- Calling 911 after epinephrine administration
- Medical identification jewelry
Immunotherapy Considerations
- Allergen immunotherapy for kiwi-related OAS remains investigational 1
- Some evidence suggests that immunotherapy directed at cross-reacting birch pollen may reduce OAS symptoms in select patients, though results are inconsistent 1
- Sublingual immunotherapy (SLIT) with kiwi has been studied with low side effect profiles but limited long-term data 1
- Current guidelines do not support routine immunotherapy for food allergy outside research settings 1
Follow-Up Care
- Refer to allergist for comprehensive evaluation including: 1
- Skin prick testing with fresh kiwi (prick-by-prick)
- Specific IgE testing for kiwi components (Act d 1, Act d 2, Act d 5, Act d 8, Act d 10) 3
- Assessment for cross-reactive allergens
- Nutritional counseling if multiple food avoidances are necessary 1
Important caveat: Even patients with isolated OAS can develop systemic reactions upon subsequent exposures, particularly if larger quantities are consumed or if the fruit is fully ripe 2, 4, 5. One case report documented anaphylactic shock requiring gastric decontamination when kiwi pulp remained in the stomach 5.