What should you know about IgE-mediated food allergy?

The immune system makes IgE antibodies against a food protein. When that food is eaten, immune cells can release chemicals that cause itching, hives, lip or facial swelling, vomiting, cough or breathing difficulty. An itchy throat can be an early symptom, but symptoms vary between reactions. A specific IgE blood result may support the diagnosis; it does not alone prove that a food caused symptoms or predict the severity of a future exposure.

Record the food, amount, preparation, timing and symptoms, then arrange an allergy assessment. Avoid a suspected trigger as advised, check ingredient labels carefully and tell restaurants about the allergy. Do not test your tolerance at home. Ask whether you need prescribed adrenaline and a written emergency plan. [Allergy Testing](/treatments/diagnostics-and-screening/allergy-testing/) can help connect a history with targeted results. [Food Allergy](/conditions/food-allergy/) guidance can support day-to-day planning.

Use prescribed adrenaline and call emergency services for trouble breathing, throat or tongue swelling, faintness, confusion, repeated vomiting, or symptoms affecting more than one body system. Do not wait for a test result. These features may indicate [Anaphylaxis](/conditions/anaphylaxis/), which needs immediate [Anaphylaxis Emergency Treatment](/treatments/acute-and-urgent-care/anaphylaxis-emergency-treatment/).

Ask whether your history fits IgE-mediated allergy, which foods need testing, how to read labels, and whether related ingredients require avoidance. Ask how to use adrenaline, when to repeat it if symptoms persist, and which people around you should know the emergency plan.