Food Allergies

Definition

• Immune system response where body mistakenly identifies a specific food protein as harmful. This will trigger release of chemicals like histamines that can cause symptoms such as hives, swelling, and/or life threatening anaphylaxis.

Common Types 

• Immunoglobulin E (IgE) mediated 

  • Specific food causes body's immune system to make antibodies called immunoglobulin E (IgE). These IgE antibodies will react with certain food and cause symptoms. 

    • Top foods causing food allergies 

      • Milk 

      • Egg

      • Peanut

      • Tree Nut

      • Soy

      • Wheat 

      • Sesame 

      • Fish 

      • Shellfish 

• Non-IgE Mediated 

  • The body's immune system react to certain foods but does not involve an IgE antibody. A person can have both IgE mediated and non-IgE mediated food allergies. 

Treatment & Management 

• Blood Serum Testing  (IgE testing) 

  • Can be used as a complement to the patient's clinical history. IgE tests can cause false positive results that can lead to avoidance of certain food.  

• Skin Prick Testing 

  • Checks for immediate allergic reactions by introducing tiny amounts of a suspected food allergen under your skin. 

  • If a raised, itchy bump (wheal) appears, it indicates the presence of food-specific IgE antibodies. About 50-60 percent of all SPTs yield “false positive” results, meaning that the test shows positive even though you are not really allergic to the food being tested. 

• Oral Food Challenge 

  • Gold standard for food allergies. 

  • A medically supervised procedure where a patient consumes a suspected allergen in gradually increasing amounts to definitively diagnose or rule out a food allergy.

• Food Elimination Diet 

  • A process where the patient temporarily removes potentially irritating or allergenic foods for 2 to 4 weeks, followed by medically supervised re-introduction to identify symptom triggers. 

Clinical Pearls 

• A food allergy involves an immune response and is different than a food intolerance which does not involve the immune system. 

• Early introduction is key: Introduce peanut products like thinned peanut butter or peanut puffs around 4 to 6 months of age. Whole peanuts are a choking hazard.

• iREACH Parent/Caregiver Handout - Peanut and Solid Food Introduction

• CFAAR Early Peanut Recommendation - Clinician Work Flow

• Clinical Resource: Interpreting Serum-Specific IgE Panels: Key Insights for Pediatricians in Diagnosing Food Allergies in Children (Fashho, 2025) 

  • Take a detailed history: Determine whether the patient experienced a reaction (ex: urticaria, angioedema, vomiting, respiratory symptoms) within 30 minutes to 2 hours after consuming a specific food. 

  • Assess prior food consumption. 

  • Consider the impact of eczema. 

Resources

• American Association of Nurse Practitioners (AANP) - Point of Care Tool Food Allergy

• American College of Allergy, Asthma, & Immunology - Food Allergies

• Allergy & Asthma Network - Food Allergies

• American Academy of Asthma, Allergy, & Immunology - Food Allergies

• Asthma and Allergy Foundation of America - Food Allergies

• Center for Food Allergy & Asthma Research (CFAAR)

• Food Allergy & Anaphylaxis Connection Team (FAACT) - Food Allergies

• FAMP-IT: Food Allergy Management and Prevention Support Tool for Infants and Toddlers

• Food Allergy Research & Education (FARE) - Food Allergy 101

• Food Allergy Nursing Association (FANA) - Monthly Speaker Series

• National Association of School Nurses (NASN) - Allergies & Anaphylaxis

SIG Member Publications

• Articles in the Journal of Pediatric Health Care can be found by searching articles tagged food allergies in the JPHC