Wheeze in children under 5 years old

Wheeze in children under 5 years of age is often triggered by a viral infection.

The cause of wheeze in children depends on their age and other symptoms and risk factors, such as a family history of asthma. 

Common causes include the following:

• Bronchiolitis – this is the most common cause of wheeze in children under 1 year of age. Bronchiolitis is a viral infection that affects babies' lungs. Read more about bronchiolitis. 
• Viral upper respiratory tract infection or viral-induced wheeze – this is the most common cause of wheeze in children 1 to 4 years of age and happens when your child has a common cold or a chest infection. Your child is usually well in between the infections. 
• Pre-school asthma – pre-school asthma can be the cause of wheeze in tamariki, especially if there is a family history of asthma or allergies. If your child has been diagnosed with pre-school asthma, it doesn't necessarily mean they'll have asthma at school age or older. Only about half of those children will. Regular appointments are needed to assess your child's asthma and treatment. Read more about asthma in children. 
• Bronchiectasis – this is a chronic lung condition resulting in bacterial infections and can be the cause of wheeze if your child also has a wet-sounding cough that lasts for weeks. Read more about bronchiectasis.
• Foreign body inhalation – this usually causes wheeze that is noticed after a choking episode. 

Your child most likely has asthma if the wheeze happens:

• at night or when they wake up 
• during or after exercise
• when there is a trigger such as cold weather, dust, pollen, smoke, grass or certain foods
• when your child is otherwise well.

Asthma is also more likely if your child has eczema or other allergies including hay fever, or a family history of asthma or allergy. 

Your healthcare provider will ask you about your child's wheeze, including how long they have been wheezing, any triggers and whether it comes and goes. They will also ask about other symptoms, such as a cough, breathing difficulties, runny nose or sore throat. Your healthcare provider should also listen to your child's lungs.

Sometimes blood tests are needed to find out the cause of the wheeze, depending on what your healthcare provider thinks is causing it. A chest X-ray is usually not needed. 

In some cases, the cause of your child's wheeze may not be diagnosed straight away and the diagnosis may change over time. Asthma reliever medications, such as salbutamol used with a spacer, may be used. Asthma preventer medications may also be required for a period of time. This may then require multiple appointments to assess your child's symptoms and response to treatment. 

Treatment depends on the likely cause of your child's wheeze. 

Lifestyle changes

• Reduce your child's exposure to cigarette smoke and don't smoke or vape around your child. 
• Keep your home warm and dry. If this is difficult to do, ask your GP or doctor if you are eligible for social support or local housing services. 
• Make sure your child's vaccinations and your own vaccinations are up to date.
• Make sure everyone in your household washes their hands often to help prevent the spread of infections. 
• Avoid triggers such as grass, pollen, dust or certain food if it is known to cause your child's wheeze.

Medicine

Common medicines that may be prescribed for your children include:

• salbutamol inhalers or relievers
• corticosteroids inhalers or preventers
• oral montelukast
• oral antibiotics for bacterial infections.

Always use an aerosol inhaler with a spacer. Spacers make the inhalers much more effective. Read more about spacers. 

Image credit: Healthify He Puna Waiora

You will probably need to visit your healthcare provider multiple times to review your child's medicines and response to treatment, especially if your child is diagnosed with pre-school asthma. Your child may outgrow their symptoms and the diagnosis may change. 

Apps reviewed by Healthify

You may find it useful to look at some asthma apps, breathing apps, and first aid and emergency apps.

About half of children will grow out of their symptoms by school age. 

Asthma New Zealand(external link) provides education, training and support to individuals with asthma and their families.