Food Challenges

Please note, this page is printable by selecting the normal print options on your computer.

Information for parents and carers

Food challenges are tests that are performed in hospital to see if your child is allergic to or able to tolerate a particular food. The aim of this leaflet is to give you an explanation of what to expect when your child has a food challenge at the Children’s Allergy Service, Milton Keynes University Hospital. If you have any questions or concerns, please do not hesitate to contact the children’s allergy team – details are given at the end of this information leaflet.

What is a food challenge?
A food challenge is when a certain food, which we suspect your child may have an allergy to, is fed to your child under close medical supervision. This is done by gradually giving bigger doses of the
suspected food over a certain amount of time, until a reaction occurs or the ‘top dose’ is eaten without any adverse reaction. The ‘top dose’ is what a child would be expected to eat in a normal portion. A food challenge usually lasts for up to five hours.

What are the benefits of having a food challenge?
A food challenge will confirm whether your child has a food allergy or not. Dependent on the outcome, you may be able to (re)introduce this particular food back into your child’s diet. This may help you and your family lead a more normal life, without fear of your child reacting to a certain food. If you find out as a result of the food challenge that your child is allergic to a particular food, you will then be able to exclude that food from your child’s diet and pass this information on to your child’s school or nursery.

How has the decision been made for my child to have a food challenge?
The decision for your child to have a food challenge was made jointly by you, your child and by the doctor or nurse that you saw at your child’s allergy clinic appointment. The food that we will be testing has been chosen by you and your child. This is usually because you would like for your child to start eating this food as it will help to make his/her life easier. You will have discussed with either doctor or nurse at the clinic what has happened to your child when they have eaten certain foods in the past. Your child will have been allergy tested (using skin prick or blood testing) at their clinic appointment, however your child’s history and test results have suggested that your child’s allergy may have resolved or it is unclear if a certain food has caused your child’s allergy or not.

Therefore the only way to know for certain if your child is allergic to a particular food is for them to eat it in a safe environment with the allergy team and any medications they might need in case of an allergic reaction close at hand.

Are there any risks associated with having a food challenge?
There is a potential risk that your child will have a reaction to the food they are being challenged to. This is why the food challenge is done in a hospital setting. Your child will be closely observed by a paediatric nurse who will monitor him/her for any signs of allergic reaction, such as an itchy rash or breathing difficulties. A doctor will always be available if needed. If your child does have an allergic reaction, they should stop eating the food immediately. A relevant medicine will be given to relieve the symptoms and to stop the reaction from getting worse – this may be an antihistamine such as Chlorphenamine (Piriton®) or in the case of a severe reaction, adrenaline (Epipen® or Jext®).

What are the alternatives to my child having a food challenge?
You may choose for your child not to have a food challenge and just continue to avoid the food they might be allergic to. Your child may grow out of an allergy, however a food challenge is the only safe and definitive way to find out whether your child has a food allergy or not.

What should I do to prepare my child for the food challenge?
Preparing your child for their visit to hospital will help them to understand what is happening and can improve your child’s willingness to cooperate. Talking to your child in advance will give them time to ask any questions or voice any concerns they may have. Use familiar words that your child will understand and give truthful, factual information. Explain that your child will meet the doctors and nurses and that they should only have to stay in hospital for half a day.

You may wish to bring some familiar toys or books with you to help your child feel at ease while they are with us. Your child can eat and drink as usual during the challenge, so please bring food, such as a packed lunch, for your child to eat. You will also be asked to bring the test food with you.

Some medicines can affect the result of the food challenge and may need to be stopped ahead of time. We will try to contact you up to a week before your child’s appointment to confirm your attendance and answer any questions you may have. If we have been unable to contact you, please ensure that you have spoken to us before you attend your appointment. Our contact number can be found below:

Paediatric Day Care Unit: 01908 996373

What happens during the food challenge?
On arrival your child will be seen by a doctor or a nurse who will take your child’s temperature, pulse and blood pressure. We will continue to monitor these throughout the day. The food challenge
procedure will be explained to you and your child, including the risks and benefits. You will then be asked to sign a consent form. Please do not hesitate to ask the nurses or doctors any questions
you may have. If your child is having a food challenge, they will be given increasing amounts of the food they are being challenged to. The amount given will vary according to each food. The food will be given at 20 minute intervals. It may be necessary to hide the challenge food in a food familiar to your child to make sure he/she eats the required amount (for example, mixing cow’s milk with soya milk). Please bring some of your child’s favourite foods with you for this purpose. The table below offers some suggestions:

Allergen Ways of introducing the food
Cow’s milk Mix with yoghurt or whatever their
current milk is (for example soya
milk) or pour over cereal.
Cooked egg Eggs as an omelette or hard-boiled. Bring bread to make sandwiches or
rice to mix the egg into.
Nuts Nut butters, chocolate spread to mix
with the nut butters, chopped or
ground nuts to mix into yoghurts and
jelly, biscuits to spread the butters on
to. For suspected peanut allergies,
Bamba snacks containing peanut
butter are available in supermarkets.
Fish Fish fingers, bread and ketchup to
make sandwiches or rice to mix with
the fish.

Your child will be checked for signs of an allergic reaction before each dose of food is given. If your child has an allergic reaction at any point during the challenge, the challenge will be stopped
immediately. We will treat your child according to how the reaction occurs, and your child will be monitored until the reaction settles and you are able to go home.

What happens after the food challenge?
What happens next depends on whether your child receives a positive or negative test result.

A positive test result
This is when your child reacts to any of the doses of food given. A positive reaction means your child is allergic and needs to strictly avoid that food. The doctors and nurses will treat the reaction as
needed, and your child will be monitored for two to four hours after a reaction. Occasionally children may need to be observed for a longer period and therefore may need to stay in hospital overnight.

A negative test result
This is when no reaction occurs to any of the doses of food. Your child will need to stay with us for two hours following a food challenge.

Are there any follow-up appointments?
We will talk with you about this during the food challenge visit. Usually the doctor who saw your child originally in clinic will review your child again about a year after the challenge. The nurses will talk with you about any changes in your child’s treatment or diet before you go home. We will send you and your child’s GP a letter with information about the challenge result.

Milton Keynes University Hospital NHS
Foundation Trust
Standing Way
Milton Keynes, MK6 5LD
©Milton Keynes University Hospital NHS Foundation Trust

We ask for information about you so that you can receive proper care and treatment. This information remains confidential and is stored securely by the Trust in accordance with the provisions of the Data Protection Act 2018/GDPR. Further guidance can be found within our privacy notice at found on our Trust website at

Contact us
If you have any questions or concerns about food challenge, please contact Paediatric Day Care Unit on 01908 996373. If you would like to cancel or change your child’s appointment please telephone 01908 996373.

Patient Advice and Liaison Service (PALS)
To make comments or raise concerns about the Trust’s services, please contact PALS. Ask a member of staff to direct you to the PALS office or call 01908 995954. Email: [email protected]

Information has been provided by Guy’s and St Thomas’s NHS Foundation Trust Evelina London.