Food Allergy

Diagnosis

There is no single test that can definitively confirm or rule out a food allergy. Your healthcare team will review several factors before making a diagnosis, including your medical history, symptoms, and test results.

Key diagnostic steps may include:

• Symptom review: You or your child’s healthcare provider will ask about symptoms, including which foods and how much seem to cause problems.

• Family history: Information about family members with allergies of any kind can help identify patterns of allergic conditions.

• Physical examination: A detailed exam helps identify or exclude other medical causes of symptoms.

• Skin test: During a skin prick test, small amounts of suspected foods are placed on your skin, and the skin is pricked to allow minimal exposure. If you’re allergic, a small raised bump develops. However, a positive result doesn’t confirm a food allergy on its own.

• Blood test: A blood sample is tested to measure levels of immunoglobulin E (IgE), an antibody linked to allergic reactions.

• Elimination diet: You may be advised to remove suspected foods for 1–2 weeks, then reintroduce them gradually to identify triggers. However, this should be done under medical supervision, especially if you have a history of severe reactions.

• Oral food challenge: Performed in a medical setting, this test involves eating small, increasing amounts of the suspected food under supervision to confirm whether it causes symptoms.

Treatment

The most effective way to manage a food allergy is to avoid foods that trigger allergic reactions. However, accidental exposure can still occur, and treatment depends on the severity of symptoms.

• Mild allergic reactions: Nonprescription or prescribed antihistamines may help reduce itching, redness, or hives. They can be taken after accidental exposure but are not suitable for severe reactions.

• Severe allergic reactions (anaphylaxis): Emergency treatment with epinephrine is essential. Many people with severe allergies carry an epinephrine autoinjector, such as an EpiPen or Adrenaclick.

If prescribed an autoinjector:

• Learn how to use it properly and teach close contacts how to administer it in an emergency.

• Carry it with you at all times, with an extra device kept at work or in your car.

• Replace it before the expiration date to ensure effectiveness.

Emerging Treatments

Research continues to explore ways to reduce or prevent allergic reactions to foods.

• Omalizumab (Xolair): This monoclonal antibody helps reduce allergic reactions to multiple foods in adults and children aged 1 year and older. It is given by injection and may lessen the severity of reactions if accidental exposure occurs.

• Palforzia: This oral immunotherapy drug is approved for children aged 4 to 17 with confirmed peanut allergy. It helps reduce the risk of severe reactions but isn’t suitable for individuals with uncontrolled asthma or certain gastrointestinal conditions.

• Immunotherapy approaches: Experimental treatments include oral and sublingual immunotherapy, which involve exposing the patient to small, gradually increasing doses of the allergen to help build tolerance over time.

Currently, these emerging options are used only under strict medical supervision, as they are still being studied for safety and long-term effectiveness.