Last updated:

Reviewed by:

Dr Bryony Henderson

, Lead GP at Livi

Medically reviewed

Croup is a common childhood condition, which causes a barking cough. Find out about the symptoms of croup and when to seek help for your child.

What is croup?

Croup is caused by a viral infection, and affects the upper airways of young children. It causes swelling of the trachea (windpipe) and larynx (voicebox) which can make it harder to breathe. Croup is most common between the ages of 6 months and 3 years.

What are the symptoms of croup?

Children and babies with croup might initially have symptoms of a normal cold, such as a runny nose, raised temperature and slight cough. 

As the upper airways become inflamed and swollen, your child may develop a harsh cough. Some people describe the croup cough as sounding like a ‘seal’s bark.’

Other symptoms of croup can include stridor, which is when your child’s breathing becomes noisy and high-pitched, particularly when breathing in. This happens due to the narrowing of their upper airways, which disrupts the flow of air. They may also have a hoarse voice or lose their voice completely.

The symptoms of croup are typically worse at night, and may wake your child up. It is also common for symptoms to worsen throughout the day.

Severe croup is diagnosed when a child has a barking cough and the following symptoms:

  • Stridor (noisy breathing)

  • Sucking in of the muscles between or around their ribs and laboured breathing

  • Agitation or lethargy

Croup in adults is rarer, and usually adults only develop a mild cough, runny nose and low-grade fever. Adults have larger airways, so they are less likely to develop the characteristic barking cough or stridor (noisy breathing) which are seen in children.

What causes croup?

Croup is usually caused by the parainfluenza virus, but it can be caused by other common viruses such as influenza, respiratory syncytial virus (RSV) and adenovirus.

How is croup diagnosed?

Croup can be diagnosed by a GP who might listen to your child’s cough and assess their breathing.

How is croup treated?

Croup can usually be treated at home, and you should encourage your child to rest and drink plenty of fluids. You can also give your child paracetamol to bring down their fever and reduce any pain. Symptoms normally resolve in about 48 hours but can last up to a week. 

Your child may be given a single dose of dexamethasone by your doctor, which is a steroid that can help to reduce inflammation in their airways and it may reduce the length of the illness too.

When should I speak to a doctor?

If you’re worried your child may have croup, you should call NHS 111 or contact a GP. Croup is usually mild, but in some cases it may be severe. 

You should take your child to A&E or call 999 if they are:

  • Struggling to breathe

  • Have an increased breathing rate or you can’t hear them breathing at all

  • Agitated or distressed

  • Lethargic or abnormally drowsy

  • Unable to drink

  • Have mottled, pale or blue-tinged skin

  • Sucking in the skin around their ribs and chest, making their ribs and bones in their chest more visible when they breathe

 Babies or children with croup who are having trouble with their breathing may need to be admitted to hospital for support. This might involve having oxygen through a mask, or being given steroid medications to make it easier for them to breathe.

What can Livi do?

A Livi healthcare professional can assess your child’s symptoms and make a recommendation for what steps to take next. They will be able to check how they are breathing, listen for a cough and will talk to you about how they are eating, drinking and behaving. They might recommend that your child is seen for a physical examination and your Livi healthcare professional will be able to direct you to the best place for your child. 

Last updated:
Reviewed by:
Dr Bryony Henderson, Lead GP at Livi