What is asthma?

Asthma is a common condition affecting the airways. These are the passages that allow air to flow into and out of the lungs.

People with asthma have sensitive airways. When something triggers a reaction in their airways, three main changes cause symptoms and make it harder to breathe:

1. The airways get swollen and inflamed
2. The inflammation creates a sticky mucus that clogs up the airways
3. The thin muscles inside the airways tighten and get narrower. This makes breathing harder.

Many children will outgrow asthma before they start high school. While there is no cure for the condition, almost all children with asthma can play sport and lead active lives with the right treatment and management.

Asthma flare-ups

When asthma symptoms get worse than normal, it is called a flare-up, exacerbation, episode or asthma attack. A flare-up can happen quickly or develop slowly.

Air gets trapped inside the lungs during an asthma flare-up. This makes it harder to breathe in and out (especially out), causing symptoms like wheezing and coughing.

Why do some people get asthma?

Experts do not yet know why some people develop asthma and others do not. However, there are some clear risk factors, such as:

• Family history of asthma
• Other allergic conditions like eczema, hay fever and food allergies
• Exposure to environmental triggers, such as cigarette smoke.

Wheezing is very common in babies and toddlers, but not all children who wheeze have asthma. Doctors can diagnose children with asthma from their first birthday onwards. However, most will grow out of it as they get older.

What causes asthma?

Many things can cause an asthma flare-up in someone with asthma. The most common is a viral respiratory infection, such as the common cold.

Other common asthma triggers include:

• exercise
• changes in the weather or windy conditions
• allergens such as dust mites, pollen or animal fur
• cigarette smoke or vape mist
• pollution
• some medicines.

Even the smell of cigarette smoke on clothes or furniture can trigger an asthma flare-up. Avoid smoking or vaping in your home, car or around your child.

While it is not always possible to predict an asthma flare-up, it is helpful to know possible triggers so you can reduce your child’s risk.  Some children need daily medicine to prevent asthma symptoms; others only get symptoms in certain situations – for example, after playing sport.

Signs and symptoms of asthma

The symptoms of asthma can vary from mild to severe.

Mild asthma flare-up

Most asthma flare-ups are mild. They will often last two to three days, or sometimes longer.

The three most common signs of a mild asthma flare-up are: trouble breathing, wheezing and coughing.

Trouble breathing

Your child may:

• feel out of breath while resting
• breathe fast
• have tightness in their chest
• need to work harder to breathe
• not be able to talk normally due to feeling out of breath.
• lack energy.

Wheezing

Wheezing is when your child’s breathing makes a high-pitched whistling sound – usually heard when your child breathes out.

Coughing

Coughing from asthma usually happens:

• at night or in the early hours of the morning
• when the temperature is cool
• during exercise.

If your child has a cough without wheezing or breathing problems, asthma may not be the cause.

Severe asthma flare-up

A severe asthma flare-up is more serious. Your child may:

• struggle to breathe and become very upset
• find it hard to speak a full sentence
• feel lethargic or very tired
• make deep sucking movements in their throat or chest
• have a worsening cough or wheeze.

Asthma emergency

An asthma emergency can be life-threatening. Your child may:

• be extremely short of breath
• not be able to speak more than one or two words at a time
• feel very drowsy and exhausted
• go limp or lose consciousness
• have a blue tinge around their lips.

How to care for asthma

The goal of asthma care is good asthma control. This generally means:

• Symptoms less than twice a week
• No need for care in a hospital emergency department
• No need for oral steroids
• No limits on physical activity.

See a doctor

If your child has problems breathing, wheezing or coughing, you should speak to their doctor about asthma. The more you can share about your child's symptoms, the better. Think about whether certain things seem to trigger their symptoms – for example, do they get worse when they have a cold, pat a cat, or after exercise?

A doctor may give them asthma medicine to see if it helps, if they suspect your child has asthma.

Get an Asthma Action Plan

An Asthma Action Plan explains how to prevent and manage asthma flare-ups. If your child has asthma, work with their doctor to create a customised Asthma Action Plan. You should review the plan with your child's doctor every twelve months, or sooner if their condition changes.

Keep your child’s Asthma Action Plan in a place where you can easily find it, and ensure anyone caring for them knows they have asthma and what to do during a flare-up. It is a good idea to take photos of the plan on your phone. You should also print copies for your child to carry with them and to give to their childcare or school.

Avoid asthma triggers

Help your child avoid things that you know can cause asthma symptoms. For example, if pollen triggers their asthma, you may want to keep them inside on forecast high-pollen days. If dust gives them symptoms, you may need to vacuum their room more often.

Know your medicines

There are two common types of medicine for children with asthma: relievers and preventers.

Both medicines come in different forms, but most are inhaled through the mouth, so they get to the lungs where they are needed. Some common devices are: metered-dose inhalers or ‘puffers,’ and dry-powder inhalers.

Relievers

• Control asthma flare-ups when they happen
• Relax muscles inside the airways so that air can get through more easily
• Works very quickly – usually in minutes
• Used during an asthma flare-up or sometimes before exercise to prevent symptoms.
  

Preventers

• Prevent asthma flare-ups and manage symptoms
• Reduce swelling and inflammation, and dry up mucus
• Needs to be taken every day, even when your child is well.
  

If your child has a preventer and/or reliever, they should see their doctor regularly. The doctor will check their dose and make sure the medicines are working properly.

It is very important to learn how to use asthma medicines, so you can support your child and make sure they get a full dose of medicine. If your child uses a puffer, they should always use a spacer to make sure more of the medicine gets to their lungs, where it is needed.

Asthma management in children

In September 2025, the Australian Asthma Handbook updated its guidelines for managing asthma in children and young people. Below are the current guidelines for different age groups in Australia. Some young people will need other treatment, based on their symptoms.

What to do during an asthma flare-up or emergency

Asthma flare-up

Follow your child’s Asthma Action Plan during an asthma flare-up. It will explain what to do and whether to increase their medicine dose.

Monitor your child's condition as you follow their Action Plan. Over time, it should get easier for them to breathe, and their other symptoms should ease. However, if their symptoms come back or do not stop, and reliever medicine does not help, this is an asthma emergency.

Asthma emergency

An Asthma Action Plan should advise what to do in an emergency, based on your child’s condition and medicines. Refer to these instructions if you can.

You can also follow the four steps of asthma first aid (sometimes called ‘4x4x4’):

1. Sit your child upright. Try to stay calm.
2. Give your child four separate puffs of a Salbutamol reliever puffer (usually blue or grey).
   • First, shake the puffer.
   • Attach a spacer, if available.
   • Put one puff into the spacer, then ask your child to take four breaths from the spacer. You may hear a click as they breathe.
   • If you do not have a spacer, your child should have four puffs directly from the puffer. Give them one puff at a time and ask them to take one slow, deep breath in and hold it as long as they can. Repeat four times.
3. Wait four minutes. If your child’s asthma does not improve, give four more puffs, then wait four more minutes.
4. Call an ambulance (000) immediately if your child still cannot breathe properly. Keep repeating step two while you wait for the ambulance.

Other asthma medicines have different emergency instructions. For example, if your child has a Terbutaline inhaler, they will only need two puffs instead of four. Follow instructions for other medicines in your child’s Asthma Action Plan.

After an asthma flare-up or emergency

Your child should see their doctor within a week of an asthma flare-up or emergency to make sure they have fully recovered. This is a good chance to review their Asthma Action Plan and ask any questions, such as when they can return to sport. If your child does not have a preventer, you may want to discuss whether it may help.

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When to get help

For more information

• Speak to your child’s doctor
• Kids Health Info: Asthma – use of spacers
• Kids Health Info: Asthma – videos
• Kids Health Info: Thunderstorm asthma
• National Asthma Council Australia: Asthma and COPD medications chart
• Health Direct: Medicines for asthma
• Better Health Channel: Asthma emergency first aid
• The National Asthma Council Australia
• Australasian Society of Clinical Immunology and Allergy

Developed by The Royal Children’s Hospital Emergency department, with input from the General Medicine, Respiratory and Complex Care departments. We acknowledge the input of RCH consumers and carers.

Reviewed November 2025

Please always seek the most recent advice from a registered and practising clinician.