What are the current treatments for food allergy?

Current Treatments for Food Allergy

The cornerstone of food allergy management remains strict dietary avoidance of the identified allergen combined with immediate access to intramuscular epinephrine for emergency treatment of accidental exposures, as no curative treatments currently exist. 1

Primary Management Strategy: Avoidance and Emergency Preparedness

Dietary Avoidance

• Complete elimination of the confirmed food allergen from the diet is the fundamental treatment approach. 1
• Avoidance must be based on confirmed clinical allergy (history of reproducible symptoms upon exposure), not merely on positive sensitization testing, as overreliance on IgE testing leads to unnecessary dietary restrictions. 1
• Nutritional consultation is strongly recommended when multiple food avoidances are required to prevent nutritional deficits. 1

Critical caveat: Nearly 89% of widespread elimination diets in children with atopic dermatitis were found to be unnecessary when based solely on serum-specific IgE without confirmed clinical reactions. 1 Avoid eliminating foods without proper diagnostic confirmation through oral food challenges when indicated.

Emergency Treatment of Reactions

Epinephrine Administration (First-Line)

• Intramuscular epinephrine into the lateral thigh (vastus lateralis) must be administered immediately upon recognition of anaphylaxis symptoms. 2, 3
• Dosing: 0.15 mg autoinjector for children 10-25 kg; 0.30 mg autoinjector for children ≥25 kg and adults. 2
• May be repeated every 5-15 minutes if symptoms persist or recur. 1, 2
• All food-allergic patients must be prescribed and carry two doses of epinephrine autoinjector at all times. 1, 2, 4

Adjunctive Medications (Secondary)

• H1 antihistamines (diphenhydramine 1-2 mg/kg, maximum 50 mg) for mild symptoms. 2, 4
• Bronchodilators (albuterol 4-8 puffs via MDI or 1.5 mL nebulized) if respiratory symptoms present. 2
• Important limitation: Antihistamines and bronchodilators cannot be relied upon to treat severe reactions (anaphylaxis)—epinephrine is mandatory. 1

Post-Reaction Management

• All patients receiving epinephrine require transport to emergency facility for 4-6 hours observation (longer for severe reactions). 2
• Biphasic reactions occur in 1-20% of cases, typically around 8 hours but potentially up to 72 hours after initial reaction. 2

Emerging Disease-Modifying Therapies

FDA-Approved Oral Immunotherapy

Palforzia (peanut protein powder) is the only FDA-approved drug for food allergy treatment, approved in 2020 for peanut allergy in children aged 4-17 years. 1

• Consists of characterized peanut powder with escalating doses leading to 300 mg daily maintenance dose. 1
• Mitigates risk of allergic reactions from accidental peanut exposure but requires continued daily dosing and strict peanut avoidance. 1
• European Medicines Agency also approved Palforzia in December 2020. 1

Investigational Immunotherapy Approaches

Oral Immunotherapy (OIT)

• Involves repeated oral exposure to incremental amounts of food allergen to induce desensitization or tolerance. 1, 5, 6
• Mechanism: promotes regulatory T cells (modulated by FoxP3), increases allergen-specific IgG4, decreases IgE. 1
• Currently used with off-the-shelf food products in some U.S. private practices, though not universally recommended. 1
• Major benefit: increases threshold of reaction, particularly for cow's milk, hen's egg, and peanut in children. 1
• Safety concerns: adverse effects range from mild oropharyngeal/skin reactions to anaphylaxis; requires careful monitoring. 1

Sublingual Immunotherapy (SLIT)

• Allergen administered as drops or tablets under the tongue or swallowed. 1
• Taken up by mucosal antigen-presenting cells (Langerhans cells, myeloid dendritic cells) via distinct mechanism from OIT. 1
• Associated with very low incidence of anaphylaxis; adverse effects generally limited to mild oropharyngeal, pruritic, or gastrointestinal symptoms. 1
• Under investigation for egg, milk, and peanut allergy in NIH-sponsored studies. 1

Epicutaneous Immunotherapy

• Emerging approach delivering allergen through skin patches. 5, 6
• Still in investigational stages with limited clinical data. 5

Geographic Variation in Practice Guidelines

United States (2014 Practice Parameter)

• Recommends absolute avoidance and epinephrine preparedness as standard. 1
• OIT with off-the-shelf products widespread in private practice despite lack of universal guideline endorsement. 1

European Academy of Allergy and Clinical Immunology (2018)

• Restricts immunotherapy to research centers or clinical centers with substantial experience. 1
• Does not support biologicals (e.g., omalizumab) alone or with immunotherapy. 1
• Emphasizes education and emergency management plan utilization. 1

Canadian Society for Allergy and Clinical Immunology

• Recommends OIT with off-the-shelf foods for desensitization in adults. 1
• Absolute contraindications: uncontrolled asthma, pregnancy. 1

Australasia (ASCIA)

• Maintains strict allergen avoidance as standard; no approved FA treatments. 1
• Few allergists currently perform OIT. 1

Essential Patient Education Components

• Written individualized emergency action plan with clear instructions for recognizing and treating reactions. 2, 4
• Education on strict allergen avoidance, including reading food labels and recognizing hidden sources. 2
• Training on proper epinephrine autoinjector technique for patients and supervising adults. 1
• Monitoring of autoinjector expiration dates with replacement plan. 2
• Referral to allergist for comprehensive evaluation and ongoing management. 2, 4

Special consideration for high-risk patients: Those with asthma have significantly higher risk for severe reactions and require particularly close monitoring and aggressive management. 1, 2