What is Croup?

Croup is a viral illness in young children, which causes narrowing of the upper airways. Several viruses can cause croup.

How does croup develop?

When you breathe, air passes through the voice box (larynx) and windpipe (trachea) into the lungs. In croup, a viral infection causes inflammation and swelling of the lining of the voice box and windpipe, which become narrowed. When the airway becomes narrowed, breathing in becomes more difficult and stridor (a harsh noise when breathing in) is heard.

Who gets croup?

Toddlers are most likely to get croup because their windpipes are softer than those of older children. When the airways become inflamed, they narrow and this results in stridor. If your child gets croup and is less than six months of age, or of school age, you should discuss it with your family doctor.

What are the signs and symptoms of croup?

The major features are a cough which is harsh and often described as ‘barking’, and stridor. The child's voice is usually hoarse too.

Stridor may only last for a few days whereas the cough may last for up to a week or so. Breathing becomes more difficult and the stridor worsens if the child becomes upset.

The symptoms of croup most often appear or worsen at night. Before the cough and breathing trouble develop, the child may have other signs of the viral illness such as a sore throat, a high temperature, red eyes, a runny nose, or a poor appetite.

What is the treatment?

Croup is caused by viruses, so antibiotics do not help and mild cases of croup can be managed at home and no medication is needed.

In moderate to severe croup, steroid medication is an effective treatment given by doctors. This reduces the swelling in your child's airway and helps them to breathe more easily. It does not change the cough but does reduce the stridor which is the most serious aspect of the illness. Steroids work for about 48 hours.

In the most severe cases, nebulised medication (a fine mist) such as adrenaline may also be given by a doctor.

How can I care for my child at home?

If you are caring for your child with mild croup at home and they become upset, keep calm and comfort your child on your lap – distress can worsen the breathing difficulty and stridor. Allow your child to breath cold air from outside by opening a window or door; but make sure they are wrapped warmly and don't get cold. Cool sips of fluid may be soothing if your child’s throat is sore and you can give paracetamol if your child is miserable with a fever or has a sore throat (you must follow the dosage instructions on the bottle as it is dangerous to give more than the recommended dose).

Steam is not recommended - it used to be commonly advised as a treatment since it was thought that steam may loosen the mucus and make it easier to breathe; however, there is little evidence that this does any good. Also, do not make a child with breathing difficulty lie down or drink fluids if they don't want to, as it could make their breathing worse.

If the croup gets worse and you are worried that it might be serious, take your child to the doctor, the nearest accident and emergency clinic or the nearest hospital emergency department for help.

How long does croup last?

Generally, croup is at its worst in the first few days of the illness. Stridor may only last for a few days while the cough may last for up to a week or so.

When should I seek help?

If your child has any of the following, go to a doctor or the nearest hospital straight away:

  • There is stridor when your child is calm.
  • You are worried your child is having increasing difficulty with their breathing.
  • Your child remains persistently upset.
  • Your child has a pale colour, a very high temperature, cool or clammy hands and feet, or is dribbling from the mouth.

You should also seek help if you become concerned for any other reason.

What happens if my child gets recurrent croup?

It is very uncommon for children to have more than one episode of croup per year for their first two or three years. If your child does have recurrent symptoms of stridor, or a barking cough (that is, several episodes each year, or episodes that continue into school age) then they should be reviewed by your family doctor. The need for a second opinion from a paediatrician (specialist in children’s health) or ENT (ear, nose and throat) specialist may be required.