Allergy Challenges

What is a challenge procedure?

A challenge involves having your child attend clinic and, under medical supervision, is then slowly and gradually given increasing amounts of a food or antibiotic, to determine if they are allergic or tolerant to it.

Why is a challenge performed?

A challenge procedure definitively determines if your child is or isn’t allergic to the particular food or challenge. Your doctor may have ordered the challenge test for a variety of reasons, most commonly because:

  • Your child never eaten the food, but have had a skin test which is positive to the food
  • Your child has previously had an allergic reaction to the food, but now the skin test is lower and they may have outgrown their allergy
  • Your child may be allergic to fresh milk or whole egg, but potentially tolerant to small amounts of baked egg or baked milk in a cake/muffin

How is a challenge performed?

Your child will have their challenge performed under medical supervision in a clinic setting. This usually involves your child coming in for approximately 3-4 hours either in the morning (8.30am-12.30pm) or afternoon (12.30-4.00pm).

Your child will generally be looked after by an specialist allergy nurse, and initially a very small amount of the food (e.g. 1/8 of a teaspoon of peanut butter) will given. If this is tolerated, then the dose is gradually increased every 15-20 minutes until a full serve (e.g. 2 teaspoons of peanut butter) is given

What are the possible outcomes of a challenge?

There are two usual outcomes, and that is

  • Your child has an allergic reaction – in which case usually antihistamine (e.g. Zyrtec) will be given to make your child feel better, or
  • Your child is tolerant to a full serve – in which case your child will then continue eating the food on a daily basis for the next 7 days.  After 7 days, a nurse will contact you (to confirm that no reactions has occurred at home) to confirm that your child remains tolerant to the food.

How safe is a challenge?

Very safe. We are very careful with performing our challenge procedure, initially through careful selection. We reduce the chances of a severe reaction occurring by ensuring your child is well at the time of the challenge, and has had no troublesome asthma.

As the challenge is conducted through slow administration of initially small quantities of the food or antibiotic, majority of allergic reactions (90-95%) are mild, consisting of hives, lip swelling, abdominal pain.

If your child has an allergic reaction, the chances of anaphylaxis (difficulties breathing, throat tightness, persistent coughing) are low, typically between 5-10%. If anaphylaxis does occur, majority will require only a single dose of an adrenaline injection.

What happens when my child has been deemed to have passed a challenge?

We will write a letter to your referring doctor to inform them that your child has passed the food or antibiotic challenge. If your child has passed a food challenge test, we recommend that they now incorporate the food into the diet as part of the regular diet, typically 2-3 times per week or whatever is practical

Regular ingestion of the food may help ensure that tolerance is maintained and that the body “remembers” that the food is OK.

Food challenge

On the day

What do I need to prepare & bring for the challenge?

 

  1. Bring our Medicare card
  2. Bring your GP referral (if it has expired)
  3. Bring any “special” cup or bowl that your child likes
  4. Bring a couple of suitable activities for your child, remembering that a challenge can take up to 4 hours eg. Playing cards, iPad, puzzles, colouring books
  5. Bring along a change of clothes for your child and yourself (just in case)
  6. As space is limited in the clinic, we can only accommodate one parent. Please do make separate arrangements for other children.
  7. Before the appointment, if your child is hungry, please let them only have a light, non-fatty meal. This will help prevent prolonged absorption and a delayed allergic reaction during the challenge.
  8. For a food challenge
    • Please along the a) challenge-food, and b) something to mix the challenge-food with if desired. The tables on the next page will provide you with a guide.
    • Please ensure that the food used to mix the challenge-food with is something which your child is normally able to tolerate.
  9. For an antibiotic or medication challenge
    • Please bring along the relevant antibiotic or medication
    • Your specialist will have already provided you with the script for the antibiotic or medication at the time of the consultation
    • Please ensure that the script is filled with a pharmacist on the week of the challenge
  10. Please ensure your child has no significant exercise/running activities during or after the challenge, as this may increase the risk of a serious allergic reaction.

IMPORTANT INFORMATION

On the challenge week: What do I have to prepare for the challenge?

 

1.  Please ensure that your child is well with no viral infection.

  • If your child is unwell with a virus (runny nose, cough, fevers) this increases the chance of a severe allergic reaction occurring.
  • Action: Please immediately call MACCS on 03 9345 6888 to discuss and possibly reschedule the challenge

2.  If your child has asthma, please ensure that this is well controlled

  • If your child is unwell with asthma, this also increases the likelihood of a severe allergic reaction occurring
  • We consider asthma to be poorly controlled if your child has symptoms of asthma (coughing, wheezing, chest tightness) and needing Ventolin 2 times/week or more leading up to the challenge
  • Action: Please arrange to see your GP for an asthma review and immediately call MACCS on 03 9345 6888

3. Please ensure that your child has not had any antihistamines for at least 5 days before the challenge

  • If your child has taken an antihistamine within 5 days, this may potentially mask a true allergic reaction occurring
  • Please do not discontinue your child’s usual asthma preventers (Flixotide/Seretide) and nasal sprays
  • Action: Please immediately call MACCS on 03 9345 6888 to discuss and possibly reschedule the challenge
Challenge food What to Bring Suggested carrier foods
Cow milk Cow milk formula (for babies)
Fresh cow's milk (for children > 1yo)
Not usually required however if child does not like the taste bring flavoured toppings/nesquik
Soy milk Soy milk formula (for babies) Fresh soy milk (for children > 1yo) Not usually required however if your child does not like the taste bring flavoured topping/nesquik
Cooked Egg Raw 2x raw eggs Cooked Egg - sauce, avocado, pureed vegies, Raw Egg - Yoghurt, thick shake, ice cream, pureed fruit
Wheat 1 cup plain wheat flour Pureed fruit/vegies, smoothie, yoghurt,
Peanuts Smooth peanut butter Or 50 – 100gm ground nut Biscuits/crackers/bread If using ground nut – yoghurt, ice cream, smoothies, custard
Tree nuts 50-100g of the ground nut that is to be challenged Yoghurt, thick shake/smoothie, ice-cream, pureed fruit or vegies, custard
Sesame Seed Tahini paste Sesame Biscuits/bread, Bread and butter or yoghurt, pureed fruit or vegies
Meat/Fish I child’s serve: cooked (around 250g) Sauce, soy sauce, pureed vegies
Melted cheese 2x slices Kraft cheese, 2 x slices bread To be baked for 13 minutes at 220 at MACCS
Baked milk See below recipe You can add icing to cupcakes or put fruit in eg, raspberries
Baked egg See below recipe You can add icing to cupcakes or put fruit in eg, raspberries

Recipe

BAKED EGG MUFFIN RECIPE

Muffin ingredients (12 muffins)

  • 100 g of room temperature butter or Nuttelex margarine (or other milk free margarine if cow’s milk allergic)
  • 160 g of sugar
  • 220 g of sifted self-raising flour (if allergic to wheat, use appropriate flour e.g. soy, rice)
  • 125 mL of milk child is tolerant to (e.g. cow’s, soy, rice etc)
  • 2 large (50 g) sized eggs (room temperature)
  • Muffin tray (12 muffins) and muffin cups

Instructions

  1. Pre-heat conventional oven to 180°C (fan force oven 165°C)
  2. Mix butter and sugar until creamy
  3. Add 2 eggs and mix
  4. Add flour & milk and combine on low speed
  5. Place muffin cups into the tray
  6. Distribute batter evenly into each muffin cup
  7. Bake for 20 mins or until slightly golden brown and firm to touch

 

On the day

  • Bring 2 muffins for the challenge
  • The challenge will consist of a maximum of one whole muffin

BAKED MILK MUFFIN RECIPE

Muffin ingredients (10 muffins)

  • 125 g of butter at room temperature
  • 160 g of sugar
  • 220 g of sifted self-raising flour (if allergic to wheat, use appropriate flour e.g. soy, rice and baking powder – approx. 1 tsp if required)
  • 250 mL of cow milk
  • 2 eggs or egg substitute (room temperature)
  • Muffin tray (12 muffins) and use only 10 muffin cups**

 

Instructions

  1. Pre-heat conventional oven to 180°C (fan force oven 165°C)
  2. Add softened butter and sugar & mix on low speed until creamy
  3. Add 2 eggs and mix on low speed until combined
  4. Add alternative equal amounts of sifted flour & cow milk while mixing on low speed until all flour and milk has been added
  5. Combine ingredients on medium speed until smooth
  6. Add optional 1 teaspoon vanilla essence
  7. Place muffin cups into the tray
  8. Distribute batter evenly into each of 10 muffin cups
  9. Bake for 20-25 mins or until slightly golden brown and firm to touch

 

On the day

  • Bring 2 muffins for the challenge
  • The challenge will consist of a maximum of one whole muffin