How to recognise common breathing noises in children: wheeze, stridor and chestiness

Why does my child’s breathing sound different when they’re unwell?

Respiratory infections can cause swelling, inflammation or mucus in the airways. This changes the flow of air and creates different sounds depending on which part of the airway is affected.

What is wheezing?

Wheezing is a high-pitched, whistling or musical sound. It is usually heard when a child breathes out, although it can sometimes be present when breathing in. Wheezing occurs when the lower airways narrow. Young children have naturally smaller airways, which means wheezing with viral infections is common, particularly under the age of three, even without a diagnosis of asthma. It’s important to note that wheezing is typically a sound that is heard by a doctor when they listen with a stethoscope and can be difficult to interpret.

Common causes of wheeze include:

• Viral infections such as RSV
• Asthma or viral-induced wheeze
• Bronchiolitis in babies
• Allergies
• Sensitive airways following a cold

What is stridor?

Stridor is a harsh, noisy sound heard when breathing in. It comes from the upper airway, often around the voice box or windpipe.

Common causes of stridor include:

• Croup
• Swelling from viral infection
• Less commonly, allergic reactions or inhaled foreign objects

Croup is a frequent cause of stridor in young children and is often associated with a barking cough and hoarse voice. Stridor needs careful assessment, particularly if it is present when a child is calm or resting.

What is chestiness?

Chestiness describes rattly or congested breathing and coughing that sounds wet. This is usually caused by mucus sitting in the larger airways or chest.

Common causes of chestiness include:

• Viral colds
• RSV and other winter viruses
• Mild chest infections
• Mucus following a recent illness

Chestiness alone does not always indicate a serious infection. However, if it is persistent or affects breathing, feeding or sleep, medical advice should be sought.

When should I seek medical advice?

Some breathing noises and symptoms can be safely monitored at home, but there are times when it is important for your child to be assessed by a medical professional. Trust your instincts as a parent, if something does not feel right, it is always appropriate to seek advice.

Arrange medical assessment if your child has:

• Fast breathing or visible effort, such as ribs pulling in
• Ongoing or worsening wheeze
• Stridor, especially when resting or breathing quietly
• Difficulty feeding or drinking
• A high fever lasting more than a few days
• Chestiness combined with breathing difficulty
• Blue lips or changes in skin colour

Advice on fever in children is also available on the NHS website. In an emergency call 999 or attend an emergency department. If you are unsure or worried at any point, seeking professional advice is always the right thing to do.

Support from Childhealthy

Breathing problems can be distressing for families, but many childhood respiratory illnesses are mild and improve with time. Some children do need assessment to ensure they are safe and recovering well.

If you have concerns about your child’s breathing, contact the Childhealthy team for expert paediatric advice and assessment. We are here to support you and your child when you need it most. Additionally, information on the NHS website is readily available for parents who wish to read more about specific conditions - croup and bronchiolitis. 

Disclaimer: The information provided in this article is for educational purposes only and should not replace medical advice. Always consult with a healthcare professional for personalised guidance and treatment recommendations.