About croup

Croup is an infection of the upper parts of your child’s breathing (respiratory) system, and is characterised by a barking cough. It makes your child’s airways inflamed and swollen and causes thick mucus to be produced, making it difficult for air to move into and out of his or her lungs.

In the UK, about six in every 100 children will get croup each year. It mainly affects children between the ages of a few months and six years old, but children are most likely to get it when they are under three. This is because at this age, children's windpipes and airways are smaller and so they are more likely to become narrower if they are infected. For this reason, the symptoms are usually more severe in younger children.

Children may get croup more than once. It occurs more often during the autumn and spring in the UK.

Symptoms of croup

The most obvious symptom of croup is your child having a barking cough, which may start suddenly during the night. The cough has been compared to the noise made by a seal. Your child may have a runny nose, sore throat and mild fever (38–39°C) for a few days before the cough starts.

Other symptoms of croup include:

  • noisy breathing – a rasping sound when breathing in or wheezing when breathing out
  • hoarse throat
  • other problems with breathing
  • his or her chest moving up and down more than normal during breathing
  • a high fever (40°C or more)

You may find that your child's symptoms are worse at night. Symptoms usually last between one and three days, although your child may be ill for up to one week.

These symptoms may be caused by problems other than croup. You should visit your GP for advice.

Complications of croup

Croup doesn't usually last for longer than a few days. However, occasionally children who have severe croup can develop an ear infection or pneumonia (inflammation of the lungs).

If the infection is severe, the airways can become so narrow that your child can't breathe. If this happens, your child will need to go to hospital for treatment. About five in 100 children with croup need to go to hospital (see our frequently asked questions for more information).

It's important that you contact your GP immediately if your child's condition gets worse. You should call an ambulance for emergency help if your child has a rapid heart beat, can't breathe, seems unusually sleepy, has blueness around his or her mouth or if the skin around his or her neck or ribcage is drawn in.

Causes of croup

A virus called parainfluenza causes croup in eight out of 10 children who get croup. Other viruses, including the respiratory syncytial virus and the measles virus, can cause croup. Occasionally it may be caused by bacteria.

Diagnosis of croup

Your GP will ask you about your child's symptoms and examine him or her. Your GP may also ask about your child's medical history. Usually this will be enough to diagnose croup. If your GP is at all concerned about your child’s symptoms, he or she will refer your child to the hospital paediatric unit for assessment.

If your child is having breathing problems that are becoming worse over a short space of time, or if he or she is struggling to breathe, seek immediate medical attention.

Treatment of croup

Most children who develop croup will get better within a couple of days and won't need to have any medical treatment. In some children, the infection may last up to a week.


It's important to make sure that your child drinks enough fluids, so that he or she doesn't get dehydrated. Your child's symptoms will probably be better if he or she stays as upright as possible.

Using steam to help your child recover was often recommended in the past and even used in hospitals. However, evidence for how effective this is for children with croup symptoms is lacking. Your child may find being in a steamy room upsetting, which will make his or her symptoms worse. Also, trying to provide a steam-filled environment at home could put your child at risk of scalding.


Your GP may prescribe a type of medicine called a corticosteroid. Your child is likely to receive one dose, taken by mouth, of a medicine called dexamethasone or prednisolone. These medicines are very effective at relieving the symptoms of croup and your child probably won't need any further medical treatment.

Cough medicines and decongestants don't help and you should not give these to your child.

Hospital treatment

If your child has more severe croup, he or she will need to go to hospital. This happens to about five in 100 children who have croup. See our frequently asked questions for more information.

Will my child need to go to hospital for treatment for croup?


It depends on how serious his or her condition is. Your child may also be admitted to hospital if you live a long way away or transport to the hospital is difficult.


If your child's airways are very blocked, it's possible that he or she may be admitted to hospital so the doctors can keep an eye on him or her for a while. This happens for about five in 100 children who have croup.

In hospital, doctors can help your child get more oxygen by using ‘blow-by’ oxygen, where a hose of oxygen is held near his or her nose and mouth.

Your child may need a type of corticosteroid medicine called budesonide, which has to be inhaled as a gas through a mask with a nebuliser. Some young children find this upsetting. If this doesn't help, your child may also be given an inhalation of adrenaline with a nebuliser. This is a hormone (chemical produced by your body) that can be made artificially. It causes the airways to widen and the effect lasts for about two to three hours.

If medicines don't help, your child may need to have a tube put into his or her windpipe to breathe. This happens in fewer than two in 100 children who go to hospital with croup.

Can I give my child cough medicine if he or she has croup?


There is no evidence that cough medicines are helpful with croup, and some can make breathing more difficult for your child.


It's best not to give your child cough medicine because these haven't been shown to have any benefit. In addition, it's possible that they may make it harder for your child to breathe because they contain ingredients that may make him or her feel sleepy.

There is also no evidence to prove that decongestants are helpful in treating croup. However, you may find that giving your child painkillers, such as liquid paracetamol, helps to relieve his or her symptoms. Always ask your doctor for advice and read the patient information leaflet that comes with your medicine.

Are there other conditions that can be confused with croup?


Yes, there are a number of other conditions that have similar symptoms to croup. Some of these are more serious and need urgent medical attention. If your child is having difficulty breathing, call an ambulance for emergency help.


There are some conditions that may be confused with croup because they cause the same symptoms. There are certain things that can make it easier for you to determine whether your child has croup or if it's a more serious condition.

If your child has swallowed something that becomes stuck in his or her airway, some of the symptoms may be the same as those of croup, such as coughing and difficulty breathing. However, unlike croup, if your child has something wedged in his or her airway, the symptoms will start very suddenly when your child was well seconds before.

It's possible that your child may have epiglottitis. This is caused by bacteria, usually Haemophilus influenzae, and causes your child's epiglottis to swell. The epiglottis is a flap of tissue at the back of the throat that closes when you swallow so food doesn't go into your lungs. If it's swollen, it can cause difficulty with breathing.

Epiglottitis is very rare since the introduction of the Haemophilus influenzae B (Hib) vaccination, but it's a serious condition that needs urgent medical treatment. There are some symptoms that may help you to distinguish between croup and epiglottitis. These include high fever, drooling and difficulty swallowing.

Bacterial tracheitis is another condition that may be confused with croup and has symptoms similar to epiglottitis. This is rare, but your child will need treatment with antibiotics because otherwise the infection may lead to pneumonia (inflammation of the lungs) or blood poisoning. Bacterial tracheitis usually occurs in older children.