What is anaphylaxis?

Anaphylaxis is a severe, life-threatening allergic reaction.

Anaphylaxis happens when your child reacts to something in the environment called an allergen. Allergens might be found in food, insect stings or bites, and medicines.

Allergens cause your child’s immune system to release histamine and other substances into their body. This leads to allergy symptoms, which might include anaphylaxis.

Not all children and teenagers with allergies have anaphylaxis. Mild to moderate allergic reactions are much more common than anaphylaxis.

Anaphylaxis requires urgent medical attention. If your child is having an anaphylactic reaction, first lay your child flat or keep them sitting. Don’t let your child stand or walk around. Next use an adrenaline injector like EpiPen or Anapen if one is available. Then call an ambulance – phone 000.

Anaphylaxis symptoms

If your child is having a severe allergic reaction, they might have one or more of the following signs or symptoms:

• difficult or noisy breathing
• tongue swelling
• throat swelling or tightness
• difficulty talking or a hoarse voice
• a wheeze or persistent cough
• persistent dizziness or fainting
• paleness and floppiness (in young children).

After insect stings or bites, anaphylaxis symptoms might also include severe stomach pain or vomiting.

Sometimes an anaphylactic reaction might seem like a mild reaction at first but will quickly get worse. If your child has allergies, it’s important to watch your child closely whenever they have an allergic reaction. Monitor your child until all signs of the reaction have settled.

Most anaphylaxis happens within 15-20 minutes of your child being exposed to the allergen. Sometimes it can happen up to 1-2 hours later, but rarely after that.

Anaphylaxis tests and diagnosis

If you think your child is at risk of anaphylaxis, getting a diagnosis is important. This means a doctor will need to identify what’s causing your child to have an allergic reaction.

To start the process of allergy diagnosis, you can talk to your GP. They can order some initial tests and refer you to an allergy and immunology specialist or paediatrician for allergy tests.

When your child has a confirmed allergy diagnosis, you can prepare yourself to respond to all kinds of allergic reactions, including anaphylaxis.

Most children with food allergies to egg, cow’s milk, wheat or soy bean outgrow their allergies by the time they’re in primary or secondary school. This is true even if your child has had a previous severe allergic reaction to these allergens. Peanut, tree nut, fish and shellfish allergies are more likely to be lifelong.

Anaphylaxis treatment

Adrenaline is used to treat anaphylaxis. It works very quickly to reverse the symptoms of anaphylaxis.

If your child is at risk of anaphylaxis, they’re likely to be prescribed an adrenaline injector – for example, EpiPen or Anapen.

If your child is prescribed an adrenaline injector, it’s important that you, your child and anyone else who cares for your child learn how and when to use it. Your child’s ability to use it will depend on their age and development. You or your child should carry the adrenaline injector at all times.

Your doctor should also give your child an ASCIA (Australasian Society of Clinical Immunology and Allergy) anaphylaxis action plan.

If you think your child is having a severe allergic reaction, it’s safer to give the adrenaline injector than to wait and see whether your child’s symptoms get worse. Not giving the adrenaline injector can be more harmful than giving it, even if it’s not needed.

Managing anaphylaxis

There’s no cure for allergies, but you can take steps to make it easier for you and your child to live with anaphylaxis.

Avoid the allergen

It’s very important for your child to avoid the allergen that causes anaphylaxis. This can be challenging, but there are important things you can do to help your child with this.

Here’s what you can do if your child has a food allergy:

• Read and make sure you understand all food labels. Be aware that some allergenic foods have different names. For example, cow’s milk protein might be called ‘whey’ or ‘casein’. By law the 10 most common allergens need to be plainly stated on food labels – cow’s milk, soy, egg, wheat, peanuts, tree nuts, sesame, fish, shellfish and lupin.
• Be careful when you eat out. Ask what ingredients each dish includes, how it was prepared, whether it has touched any other foods, and whether there’s any risk of cross-contamination. Most restaurants will be happy to tell you, but they might not know about the ingredients in some foods like sauces.
• Avoid foods and cutlery that could have been in contact with the allergen. This includes buffets and bain-maries (food warmers). Even tiny amounts of the allergen can cause your child to have a severe reaction.
• Teach your child not to share food. This might depend on your child’s age and ability to understand.

Here’s what to do if your child has an allergy to insect stings or bites:

• Make sure your child wears shoes when they’re outdoors. Don’t let them walk barefoot on grass.
• Avoid dressing your child in bright colours when bees or wasps are very active.
• Avoid wearing perfumes.
• Dress your child in long-sleeved shirts and long pants when you can.
• Teach your child not to drink from open soft drink cans outdoors.
• Teach your child not to disturb insects like bees or wasps.

If your child has an allergy to a medicine, let your doctor, pharmacist or dentist know before your child has any treatments or takes any medicines.

Let people know about the allergy and its management

Family, carers, babysitters, early childhood educators and teachers need to know that your child has a severe allergy. It’s a good idea for them to know how and when to use your child’s EpiPen or Anapen. They should also have a copy of your child’s anaphylaxis action plan.

Consider a medical bracelet for your child

This lets people know about your child’s particular allergy. This can be important if your child has an allergic reaction and there are no people around who know about their allergy.

Discuss allergen immunotherapy with an allergist or immunologist

You can talk with your allergist or immunologist about immunotherapy, also called desensitisation. Immunotherapy involves a specialist doctor regularly giving your child increasing doses of the allergen. This helps your child to tolerate the allergen better and reduces their symptoms. This form of treatment takes 3-5 years or longer to complete, but it’s usually very effective.

Immunotherapy is mostly used to treat a severe allergy to insect stings or bites, house dust mites and grass pollen. Immunotherapy for food allergies is an option, but only for certain situations, ages and foods.

For more information on allergies and allergy testing, treatment and management, see our articles on allergies, non-food allergies and food allergies.