What are allergies?

Allergies happen when your child reacts to something in the environment.

The thing that causes the reaction is called an allergen. Allergens include things like food, dust mites, pollens, animals, insect stings or bites, or medicines.

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

Mild to moderate allergic reactions are much more common than severe allergic reactions. Also, deaths from severe allergic reactions are rare. They tend to happen because of a delay in giving life-saving medicine to the person having the reaction.

Immediate and delayed allergic reactions

An immediate allergic reaction usually happens within minutes after your child comes into contact with or eats the substance that they’re allergic to, but it can be up to 1-2 hours afterwards.

A delayed allergic reaction usually happens many hours after exposure. It can happen anytime from a few hours up to several days after your child comes into contact with the substance they’re allergic to.

Mild or moderate allergic reaction symptoms

If your child is having a mild or moderate allergic reaction, their symptoms might include one or more of the following:

• rash, hives or welts
• swelling of the face, eyes or lips
• tingling or itchy mouth
• eczema, hay fever or asthma – these symptoms might be worse than usual
• stomach pain, vomiting or diarrhoea.

Severe allergic reaction or anaphylaxis symptoms

A severe allergic reaction is called anaphylaxis. Symptoms might include one or more of the following:

• 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.

Anaphylaxis is a life-threatening allergic reaction and needs 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.

Allergy tests and diagnosis

If you think your child might have allergies, getting a proper assessment is important.

To start this process, you can talk to your GP, who might order an initial blood test. The GP might also refer you to an allergy or immunology specialist for allergy tests.

Allergy tests might include the following:

• Skin-prick test – your child’s skin is pricked with a special device that looks a bit like a toothpick and contains a drop of a specific allergen. If a hive comes up where your child’s skin has been pricked, your child might have an allergy.
• Blood tests – the IgE antibody test checks whether your child has a high level of IgE antibodies to a specific allergen. A high level means your child is more likely to have an allergy. Your child might have this test if they can’t have skin-prick testing, or they might have it in addition to skin-prick testing.

Only your GP, allergy and immunology specialist or paediatrician can order and assess allergy tests.

You might hear about IgG food antibody testing, Vega testing, cytotoxic testing, Alcat testing, pulse testing, iridology, kinesiology, VoiceBio analysis and stool or hair analyses. These tests aren’t scientifically proven as allergy tests. Tests that are backed up by science are most likely to be accurate, safe for your child, and worth your time, money and energy.

How to treat mild to moderate allergic reactions

The way you treat an allergic reaction depends on how severe the reaction is.

Antihistamines

Giving your child a dose of antihistamine (in tablet or syrup form) is appropriate if your child is having a mild to moderate allergic reaction, including a skin rash, tingling mouth or swelling.

If your child has an allergy, it’s recommended that you have antihistamine syrup in your home first aid kit or in your bag – this way it’s handy when you need it. You don’t need a prescription to buy antihistamines in Australia.

It’s best to use antihistamine that won’t make your child sleepy. Your pharmacist or GP can advise you on the most appropriate brand for your child.

Other allergy treatments

Depending on the kind of allergic reaction your child has, they might need other treatments. For example:

• If your child has eczema, they might need anti-inflammatory treatments like corticosteroid ointments.
• If your child has hay fever, they might need nasal sprays.
• If your child has asthma, they might need medicine like Ventolin or Asmol through an inhaler.

Allergy action plan

Your doctor can also give your child an ASCIA (Australasian Society of Clinical Immunology and Allergy) action plan. The action plan usually includes important information on how to manage allergic reactions and which medicines your child should use.

If your child has an allergy, it’s especially important to maintain good control of their asthma. If your child has a severe asthma attack, call an ambulance immediately.

How to treat anaphylaxis

Children at significant risk of anaphylaxis are often prescribed adrenaline injectors – for example, EpiPen or Anapen.

If your child is prescribed an adrenaline injector, it’s important that both you and your child learn how and when to use it. Your child’s adrenaline injector should be easy to reach at all times. You can also teach family, friends, teachers and carers how to use it.

It’s also a good idea for your child to wear a medical bracelet to let other people know about your child’s particular allergy.

You can give a copy of your child’s allergy action plan to key people like family, carers, babysitters, early childhood educators and teachers.

If your child has persistent, troublesome and severe allergies to insect stings or bites, house dust mites and grass pollen, they might have immunotherapy to reduce their symptoms. Immunotherapy for food allergies is an option, but only for certain situations, ages and foods.

Allergy risk factors

Children who have other allergy problems like asthma, eczema and hay fever or family members with allergies are at increased risk of also developing allergies.