IgE or Non-IgE 0r Food Intolerance

Three types of food allergies. IgE Allergy (Anaphylaxis), Non-IgE Allergy (nightshades), Food Intolerance

What Type of Allergy Do I Have?

No one ever told you it could be a typical food allergy, or a delayed-type allergy, or a food that just doesn’t agree. And an EpiPen only works for IgE Allergies

Key Takeaways:

IgE-mediated allergies are true immune reactions with rapid, potentially life-threatening symptoms.
Non-IgE mediated allergies are also immune reactions but delayed and typically affect the gut. They are generally not life-threatening.
Food intolerances are non-immune reactions, often due to digestive issues, and are not life-threatening.

Accurate diagnosis by a healthcare professional (allergist or gastroenterologist) is crucial for proper management of these conditions. Self-diagnosis and self-treatment, especially for potential allergies, can be dangerous.

Articles

Feature	IgE-Mediated Allergy	Non-IgE Mediated Allergy	Food Intolerance
Immune System Involvement	Yes, it involves IgE antibodies and mast cells.	Yes, involves other parts of the immune system (e.g., T-cells) but not IgE.	No, does not involve the immune system
.Reaction Time	Rapid onset (minutes to 2 hours after ingestion)	.Delayed onset (hours to days after ingestion).	Variable, often within hours of ingestion.
Severity	Can be severe, potentially life-threatening (anaphylaxis).	Generally not life-threatening, but can be very uncomfortable.	Generally not life-threatening, but can be uncomfortable.
Common Symptoms	– Skin: Hives, itching, redness, swelling (angioedema), eczema – Respiratory: Sneezing, runny nose, congestion, coughing, wheezing, shortness of breath, difficulty breathing, throat tightness – Gastrointestinal: Nausea, vomiting, diarrhea, abdominal pain, cramps – Cardiovascular: Rapid/weak pulse, light-headedness, dizziness, fainting – Anaphylaxis: Multi-system involvement, drop in blood pressure, loss of consciousness.	– Gastrointestinal: Vomiting (often profuse), diarrhea, abdominal pain, bloating, colic, constipation, poor weight gain, blood/mucus in stools – Skin: Eczema – Other: Lethargy, pallors	– Gastrointestinal: Bloating, gas, diarrhea, constipation, abdominal pain, nausea – Other: Headaches, fatigue, joint pain, rashes (le
Examples of Conditions	Classic food allergies (e.g., peanut, tree nut, milk, egg, fish, shellfish, soy, wheat).	Food Protein-Induced Enterocolitis Syndrome (FPIES), Food Protein-Induced Allergic Proctocolitis (FPIAP), Eosinophilic Esophagitis (EoE).	Lactose intolerance, gluten sensitivity (non-celiac), histamine intolerance, FODMAPs intolerance.
Diagnosis:	– Skin Prick Test (SPT): Immediate wheal and flare reaction. – Blood Test (Specific IgE/RAST): Measures IgE antibodies to specific foods. – Oral Food Challenge (OFC): Gold standard, done under medical supervision.	Elimination Diet Removal of suspected food(s) followed by reintroduction. –Oral Food Challenge (OFC): May be performed in a medical setting for some conditions (e.g., FPIES). – Biopsies: For conditions like EoE. No reliable blood or skin tests	– Elimination Diet: Keeping a food diary and then systematically removing and reintroducing foods. –Hydrogen Breath Test: For lactose intolerance. No specific diagnostic tests for many intolerances.
Management	– Strict avoidance of trigger food(s). – Epinephrine auto-injector (EpiPen) for severe reactions/anaphylaxis. – Antihistamines for mild symptoms. – Oral Immunotherapy (OIT): Gradual exposure to build tolerance (for some allergies/foods). – Biologics (e.g., omalizumab/Xolair): To reduce reactions to accidental exposure	– Avoidance of trigger food(s). – Reintroduction may be possible over time as some conditions resolve with age. – Management of specific symptoms (e.g., hydration for FPIES).	– Dietary modification/reduction of problematic food/ingredient. – Enzyme supplements (e.g., lactase for lactose intolerance). – Managing symptoms with over-the-counter medications.
Prognosis	Some allergies can be outgrown (e.g., milk, egg in children), but many are lifelong (e.g., peanut, tree nut).	Many non-IgE mediated allergies, especially in infancy (e.g., FPIES, FPIAP), are often outgrown by early childhood.	Often lifelong, but severity of symptoms can vary and management can improve quality of life.