What should you know about delayed food allergy?

Food allergy involves an immune response to a food protein. Some reactions begin soon after eating, while others are less immediate or involve symptoms that are harder to connect with a particular meal. Possible features include hives, swelling, vomiting, abdominal symptoms, wheezing, or an itchy throat. Food intolerance, infection and other conditions can produce similar complaints.

Write down what you ate, when symptoms began, the amount, preparation, other foods, medicines and exercise around the event. Do not deliberately eat a suspected food again to test it. A clinician may use the history, examination and appropriate Allergy Testing to assess the pattern.

Avoid the suspected food until you have received individual medical advice, while keeping meals nutritionally varied. Read ingredient labels carefully and tell restaurants about the suspected allergy. Keep a symptom diary rather than removing many foods without guidance. If a clinician has prescribed an adrenaline device, carry it and know how to use it; follow your personal emergency plan.

Ask about Food Allergy assessment if reactions recur or affect eating. An elimination diet or food challenge should be planned with a qualified professional, because unsupervised restriction can create nutritional problems and a challenge can trigger a serious reaction.

Use prescribed emergency medicine and call emergency services immediately for trouble breathing, throat or tongue swelling, widespread hives with weakness, repeated vomiting with breathing symptoms, faintness or collapse. These can be signs of Anaphylaxis. Do not wait for a delayed reaction to become more obvious, and do not drive yourself during a severe episode.

Does the timing and symptom pattern fit allergy, intolerance or another illness? Which foods should I avoid while this is assessed? Do I need Allergy Testing or an emergency plan? What should I do if I develop an itchy throat, swelling or breathing difficulty?