FAQ
Why are food challenges performed?
Food challenges are performed to demonstrate that a person does not have a food allergy. This might be because they have “outgrown” their known food allergy or to prove they are not actually allergic to the food they are avoiding. Sometimes food challenges are performed so that a modified form of the food (e.g. egg or dairy in “baked goods” such as muffins) can be shown that it can be tolerated and included in the diet.
Can my child have a food challenge?
Challenges can only be arranged after an appointment with Dr Nickolls. If the likelihood of the person being allergic to the suspected food is low, then Dr Nickolls will suggest a challenge (or may recommend home introduction of the food). Factors to consider when deciding to go ahead with a challenge include whether your child will actually eat the food during the challenge, or if including the food in your child’s diet is going to make a significant difference to their life. There is no point having a food challenge if the food is not incorporated into the diet on a regular basis. This is due to the risk of re-developing a food allergy if the food is still avoided for a long period of time.
Will the food challenge determine if my child is “anaphylactic”?
No. Food challenges are performed to work out if a person has an allergy or not. Challenges are stopped as soon as a person shows signs of an allergic reaction. This may be after only a very small dose of the food, so they might only have a minor reaction. It is possible that if they ate more of the food they could have a more severe reaction or anaphylaxis.
what is the outcome of the challenge?
A food challenge can have 3 outcomes:
1) Negative challenge, i.e. no allergic reaction. This means the person has “passed” the challenge, and can now safely include the food in the diet as they are not allergic.
2) Positive challenge, i.e. allergic reaction. This means the person has “failed” the challenge, and should continue to avoid the food because they are allergic to it.
3) Incomplete challenge, i.e. the person does not eat enough of the challenge food to be able to determine the outcome. In this case the food needs to be continued to be avoided, until another challenge can be arranged when appropriate.
What are the risks of a food challenge?
Challenges are performed in hospital because there is a risk of an allergic reaction occurring, which can vary from mild (e.g. rash, swelling, vomiting) to severe (anaphylaxis). The risk of any reaction occurring – particularly a severe reaction – is relatively low, because:
1) A challenge will only be arranged if the history and timing of previous reactions and the skin prick test indicates that the risk of allergy is low
2) On the day of the challenge, the person having the challenge will be assessed by a doctor and nurse to ensure the challenge can be commenced
3) Strict food challenge protocols are followed
where is the challenge performed?
The challenge takes place in the Short Stay Unit at North Shore Private Hospital. This is a dedicated space staffed by Dr Nickolls and nurses experienced in paediatric food challenges. Several children will be undergoing a challenge at the same time. It takes around 4-5 hours.
what is a muffin challenge?
Baked egg and baked milk muffin challenges are performed to determine if your child with egg or dairy allergy can tolerate baked goods such as cakes, muffins or biscuits. Being able to eat egg or dairy in baked goods may make life a little easier, but there is no good evidence that it makes them outgrow the allergy any faster. If your child “passes” the muffin challenge, they still need to avoid more lightly cooked or more concentrated forms of egg or dairy (e.g. pancakes, quiche, lasagne, cheese on pizza, croissants).