Allergen challenges Paediatric Day Unit

What is an allergen challenge?

An allergen challenge involves exposure to something that the child may previously have been allergic to or suspected of being allergic to, such as food, medication or latex.

If the child has a reaction to the allergen being challenged, we will stop the challenge, treat them appropriately with medication and they will be medically reviewed.

Before attending the Paediatric Day Unit

If the child in your care is unwell on the day of challenge e.g. sickness, diarrhoea, a wheeze or a cold, a significant flare up of hay fever or eczema, the challenge will be unable to go ahead. Please contact the Paediatric Day Unit to cancel the appointment at the earliest opportunity. The contact details are at the end of this page.

Food or other allergen that you will need to bring with you

The allergen to be challenged must be provided by you. For example, peanut butter for a peanut challenge or in the case of a baked egg/baked milk challenge, the prepared product (recipe sent by allergy team). For further guidance on what to bring with you, please contact the Paediatric Day Unit.

If the child is on a specific diet, they will need a packed lunch and any snacks they may want.

Medications that you will need to bring with you

Please bring with you any medications that the child is currently taking.You will also need to bring with you the child’s reliever (blue) inhaler, spacer device and adrenaline pen (e.g. EpiPen®or Jext® device) if these have been previously prescribed.

In the very unlikely event that the child requires adrenaline and have their own pen device with them, you will be asked (with supervision) to administer this yourself to allow for practice.

What will happen when you arrive?

• The child will be weighed and have their blood pressure and pulse taken. Their oxygen levels will also be measured.
• Those children (usually age 7 or over) who are able to perform a peak flow may be asked to do so. A peak flow is a quick test that measures the air flow in the lungs.
• Children with eczema will need to show their eczema patches.

How is the allergen given?

Food challenges begin with tiny amounts of food to be eaten. If there is no reaction, gradual increasing amounts are given to your child every 20 minutes. This is until an age appropriate portion size is reached.

The challenge will be paused or stopped at the first sign of an allergic reaction.

Sometimes a food challenge may be inconclusive. In the case of a latex challenge they will be exposed to a small amount of the latex, for example by touching a latex balloon.

In the case of a medication challenge they will be given very small amounts of the medication, usually by mouth. If you think it may help, please bring in your child’s usual eating utensils.

How long will the allergen challenge take?

The child is normally able to go home after 2 to 4 hours. If they have had a reaction they may need to be observed for longer. A doctor will decide when the child can be safely discharged.

On discharge, you will be given written advice. Allergy follow-up may be offered. Please contact your lead clinician if you have not been contacted by the team after 6 weeks.

Contact information

Paediatric Day Unit

Gloucestershire Royal Hospital

Tel: 0300 422 8452

Monday to Friday, 7:00am to 7:30pm

Email: ghn-tr.pdu.nursingteam@nhs.net

Checklist

• Stop the child’s antihistamines for 5 days before the appointment.
• Bring the specific food or allergen to the appointment.
  • Bring the child’s regular medication for asthma/allergy to the appointment.