Viral-induced wheeze factsheet


Viral-induced wheeze is a common breathing problem in children under three. It happens when a child has a viral infection and gets a cough or cold. The airways in the lungs become narrow and fill with mucus, making it hard for your child to breathe properly and causing a wheezing sound when they breathe out.

Viral-induced wheeze can also be known as:

  • reactive airways disease (RAD)
  • preschool wheeze
  • childhood asthma.

Viral infections are the most common cause of wheeze, but it can also be caused by:

  • bronchomalacia – immature or floppy airways
  • asthma – a breathing condition diagnosed in older children
  • living in an environment where there is cigarette smoke.

 Signs and symptoms

Viral-induced wheeze will often start with cold and flu symptoms, including:

  • cough
  • sneezing
  • fever
  • increased snot and mucus.

Your child may then develop further symptoms and show signs of working harder than usual to breathe. 

These can include:

  • wheezing – a whistling sound when breathing out
  • faster breathing
  • flaring their nostrils when breathing in through the nose
  • retractions - when skin pulls in around the chest, neck, and ribs in an upside-down V-shape while breathing
  • bobbing their head back and forth
  • leaning forward on their arms while sitting.

If your child has wheezing or trouble breathing for the first time and doesn't have an asthma action plan, call your local doctor or go to the nearest emergency department.


Your local doctor can diagnose viral-induced wheeze. They will:

  • do a physical check of your child’s signs and symptoms
  • listen to your child's chest to hear them breathe
  • watch for signs that your child is working harder than usual to breathe.


Treatment of viral-induced wheezing will depend on:

  • how severe your child’s symptoms are
  • whether this is the first time your child has had breathing difficulty
  • what caused the wheeze to develop.

Reliver medications and oral steroids

Your child’s doctor may prescribe medicine that will open the airways and reduce inflammation.

These can include:

  • reliever medications - bronchodilators that are breathed in using an inhaler and spacer, like Ventolin® or Asmol® 
  • a short course of oral steroids taken as a syrup, like Redipred® or prednisolone.

The doctor will discuss treatment options with you and create a plan for future wheezing episodes. Antibiotics won't work for viral-induced wheezing as a virus causes it.

Treatment in hospital

Children who are very young or have more severe symptoms may need to be treated in hospital.

Treatment in the hospital aims to:

  • give breathing medications frequently, more than every three hours
  • check oxygen levels and give extra where needed
  • support with feeding and fluids.

Your child will get breathing medication and an action plan before going home from the hospital. 

You will need to make a follow-up appointment with your local doctor within a week of leaving the hospital to check your child's recovery.

Managing wheeze at home

Children who have an action plan and have had an episode of viral-induced wheeze before may be managed at home if their symptoms do not get worse.

You will need to: 

  • follow your child’s action plan 
  • give their medication as directed
  • check that their breathing is not getting worse
  • call your local doctor if you are concerned.

Share your child's action plan and medication instructions with their other caregivers, and keep your child away from cigarettes and other smoke at all times.


When to seek help

Call your local doctor or go to your nearest emergency department if your child continues wheezing in-between doses of reliever medication, or they have:

  • fast breathing
  • fast heartbeat
  • retractions - tummy and ribs sucking in when breathing
  • grunting noise when breathing out
  • breathlessness that stops them from speaking properly.

Call Triple Zero (000) for an ambulance if your child: 

  • has trouble breathing
  • has a blue, green, white, or grey colour around the lips, tongue, gums, ears, and fingernails
  • gets worse very quickly.
Last updated Wednesday 29th May 2024


This factsheet is provided for general information only. It does not constitute health advice and should not be used to diagnose or treat any health condition.

Please consult with your doctor or other health professional to make sure this information is right for you and/or your child.

The Sydney Children’s Hospitals Network does not accept responsibility for inaccuracies or omissions, the interpretation of the information, or for success or appropriateness of any treatment described in the factsheet.

© Sydney Children’s Hospitals Network 2024