Oral Food Challenges

Medically-supervised, food allergy test.

What is a supervised oral food challenge (OFC)?

A supervised oral food challenge (OFC) is the gold standard test for food allergy. As serum and skin prick testing can be falsely positive in some patients, your doctor may have suggested doing an OFC to identify whether you are or are not allergic to the food/s in question.

In addition, an OFC is sometimes done to assess whether someone has lost their food allergy.

Small and increasing doses of a food are fed to you under supervision in one of our clinics, as directed by your treating doctor. You are monitored to confirm if the food being tested causes an allergic reaction.

Most challenges take two-to-three hours to eat the required doses, followed by a period of observation after.

How do you prepare for a supervised food allergen challenge?

  • Please bring in the food/s to be challenged that day, which depends on the food allergy that is being assessed.
  • Please contact us if you are unwell before the challenge as you should not proceed.
  • Antihistamines should be ceased 1-week prior to the OFC.
  • Please discuss with your doctor if you are experiencing frequent asthma symptoms as poorly controlled asthma is a major risk factor for allergic reactions during OFC.
  • Please bring in your adrenaline autoinjector (EpiPen or Anapen) to the OFC in case of reaction.  We will always have a supply of adrenaline available if need be.
  • You will be required to stay for the whole morning until around lunchtime.  Please commit to the full time required for the challenge.
  • If you are bringing an infant for an OFC, please bring some other foods that they like and are not allergic to. Foods such a yoghurt and fruit puree can be mixed with the food being challenged.  Sometimes the new texture or taste can be off-putting for young kids.
  • Be prepared to include the food regularly after the OFC, if you pass the challenge.

Frequently Asked Questions

Congratulations! You are not allergic to that food. The challenge is called ‘negative’ and:

  • You no longer need to avoid that food.
  • You will need to regularly include the food in your diet to prevent future reactions.

If an allergic reaction occurs, the challenge is called ‘positive’, and the following occur:

  • The OFC is immediately ceased.
  • You are given medications to help treat the allergic reaction. For a mild allergic reaction, oral antihistamines (“allergy tablets”) are given. For more severe reactions, intramuscular adrenaline (such as an EpiPen) is usually required.
  • You will stay under observation for several hours to ensure you are safe before returning home.
  • You need to avoid that food in future.

OFCs should only be performed in appropriate settings where adrenaline and close medical supervision can occur.  Not all patients need or are appropriate for an OFC. Staff who are trained and experienced in the management of allergic reactions must be on hand at all times during an OFC.

Unfortunately, the tests we have available for food allergy, short of an OFC, are imperfect.  False positive and false negative skin prick and allergy blood tests do occur. In other words, not everyone with a positive skin prick test to a food will have an allergic reaction on eating that food. Hence OFCs are sometimes required to confirm or exclude food allergy.

Take back control – start your journey today.

We are a leading paediatric and adult Allergy, Immunology and Immunopathology group with clinics in the Sydney CBD and Westmead.

Our specialists hold sub-specialised qualifications in allergy and immunology, and pathology, and offer significant clinical experience.

If you have a question about a condition or treatment, or would like to book an appointment, please contact us and we will be happy to assist you.