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.
Congratulations! You are not allergic to that food. The challenge is called ‘negative’ and:
If an allergic reaction occurs, the challenge is called ‘positive’, and the following occur:
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.
