Croup symptoms

Your child will usually have symptoms of a cold before he gets croup symptoms. So he might have a runny nose, sore throat, fever and irritability. If he has croup, he’ll develop a harsh, barking cough, sometimes a hoarse voice, and then noisy breathing, which is called stridor.

The noisy breathing and cough are usually worse at night. They can also get worse if your child gets upset. In most children, the symptoms improve over a few days then disappear.

In a few children, the croup is more severe and causes trouble breathing. In this case, your child needs urgent medical attention, and sometimes observation and treatment in hospital.

Common signs of your child having trouble breathing include the following:

  • The skin (or muscles) around your child’s ribs and under her breastbone gets sucked in as she breathes.
  • Your child’s nostrils flare.
  • Your child is restless and has trouble feeding and drinking.
  • Your child won’t lie down.

Stridor is a high-pitched, squeaky sound when your child breathes in. It’s usually a sign that there’s a blockage or narrowing in the windpipe.

Stridor is also occasionally caused by a condition called epiglottitis. It might also be caused by an inhaled foreign object.

When to see your GP about croup symptoms

You should take your child to see your GP if you notice one or more of the following symptoms:

  • Your child is having trouble breathing.
  • You can easily hear your child’s noisy breathing, even when he’s resting quietly.
  • Your child’s breastbone sucks in when she breathes in.
  • Your child has trouble swallowing.

It’s always a good idea for your child to see the GP if you have any worries about his breathing.

If your child’s lips go blue, or if your child looks very sick and becomes pale and drowsy, seek medical attention immediately by dialing 000 and asking for an ambulance. Severe croup requires emergency medical attention and close observation in hospital.

Tests for croup

Your GP will diagnose croup after taking your child’s history and examining your child.

Treatment for croup

Most children with croup don’t need treatment. You can manage the symptoms in exactly the same way as for a cold.

It’s important to try and keep your child calm, because your child can have more trouble breathing if she’s upset, frightened or stressed.

Croup is most commonly caused by a virus, so antibiotics won’t work. Antibiotics treat bacterial infections only.

Steam therapy, including the use of vaporisors, doesn’t help to treat croup and is no longer recommended.

Your child might need a short course of oral prednisolone or dexamethasone (steroids) if he has more severe symptoms. This treatment can reduce your child’s symptoms quickly by helping to reduce the swelling in his windpipe. It has no long-term consequences.

A few children with croup need to go to hospital for observation, to make sure that their windpipes don’t get blocked. While in hospital, your child might initially receive adrenaline in the form of mist (nebulised adrenaline). This reduces the swelling in the windpipe very quickly while the steroids work.

Causes of croup

Croup can happen when a viral infection leads to inflammation of the windpipe (trachea) and the vocal cords (voice box).

The viruses that cause croup are usually the same viruses that cause the common cold.  The viruses that cause croup can be spread through sneezing, coughing and hand contact.


To minimise the spread of the virus that caused your child’s croup, keep your child away from child care, preschool or school while she’s sick. Your child is usually contagious for three days after the illness has started, or until her fever has gone.

Because croup can sometimes be caused by the influenza virus, the flu vaccine might reduce the chance of your child developing croup.

There are some simple things you can do to reduce your child’s chances of getting croup or passing on the virus that caused it. For example, wash your own and your child’s hands after sneezing, coughing and blowing noses, and before eating. You can also teach your child to cough into his elbow to avoid getting germs on his hands.