Croup is an infectious condition that causes inflammation and swelling of the voice box (larynx), the windpipe (trachea) and the airways (bronchi), resulting in breathing difficulties and a barking cough.
Croup is usually an illness of very young children, generally those younger than 3 years of age.
What are the symptoms of croup?
Croup generally starts like a common cold. Your child may have a slight fever, sore throat and runny nose.
After a few days (often beginning at night) a harsh, barking cough (or ‘brassy’ cough), a hoarse voice and noisy breathing develop.
Your child may find it hard to breathe, especially breathing in. Noisy breathing that is worse when breathing in is called stridor. (Wheeze is worse when breathing out.) Crying and being upset generally make the barking cough and noisy breathing worse. In severe cases stridor can be heard when children are at rest.
Episodes of croup mostly happen at night when the air is cooler, and usually settle within a couple of hours. The attacks are usually worse in the first few days of the illness.
What causes croup?
Croup is usually caused by a viral infection that causes inflammation of the airways (including the larynx, trachea and bronchi). The majority of cases of croup are caused by a parainfluenza virus.
The inflamed airways become swollen and partially blocked with mucus, causing a partial collapse of the airway when your child breathes in (rather like a bent straw).
Young children, whose windpipes are small and soft, are the most susceptible. Croup is not as common in older children because, as a child grows up, the size and strength of the windpipe increases.
How long does croup last?
Croup usually lasts for 2 to 5 days, with symptoms generally worse at night. Sometimes the cough can persist for several weeks.
Tests and diagnosis
Your doctor will ask about your child’s symptoms and perform a physical examination.
There are usually no tests needed to make the diagnosis — the main clues to the diagnosis are the symptoms, especially the distinctive cough.
Treatment for croup
If your child has croup, it’s important you take him or her to your doctor for assessment.
Your doctor may prescribe medicines even if the croup is mild, because this can prevent the symptoms from getting worse.
Medicines that can help reduce the inflammation and swelling in mild to moderate croup include:
- oral corticosteroid medicine (taken by mouth); or
- inhaled corticosteroid medicine (given by breathing in using a nebuliser).
These medicines are usually very effective, but may take up to 4 hours to have their full effect. In more urgent situations, children with croup need to be admitted to hospital.
In severe cases of croup, where the situation may be life-threatening, you should dial 000 for an ambulance so that your child can receive emergency treatment.
Emergency treatments for severe croup include:
- adrenaline (given by breathing in using a nebuliser); plus
- corticosteroid medicine (taken either orally — by mouth, injected or inhaled via a nebuliser).
As croup is caused by a virus rather than bacteria, doctors don’t prescribe antibiotics for croup.
Is croup contagious?
Croup is contagious and is usually caused by infection with a virus (most often parainfluenza virus).
Viruses can be passed from person to person via:
- breathing in airborne droplets from an infected person’s coughing and sneezing; and
- touching contaminated surfaces such as door handles or objects with your hands and then touching your mouth, nose or eyes.
Regular hand washing and cleaning of surfaces can help prevent the spread of viruses such as parainfluenza virus, but spread from person to person, especially in the same household can be difficult to avoid.
Can adults get croup?
Croup is very rare in adults.
Croup most commonly affects children aged one to 3 years, but it is possible for babies as young as 3 months and children as old as to 12 to 15 years to get croup.
How you can help your child
You can help your child to cope in the following ways.
- Sit your child up either in your arms or on soft pillows, and give them reassurance. Croup can be frightening for your child, and children who are upset may find breathing more difficult. Sitting your child upright and with their head held high and chin forward (rather than their chin sinking onto the chest) can help open up their airway.
- Give him or her something to drink to help with the sore throat.
- Paracetamol can be given if your child’s sore throat is painful, or if there is a fever.
Hot moist air has been said to help children with croup by loosening the secretions. However, there is no evidence that breathing humidified air is beneficial. Also, the risk to your child of burns from steam or hot water is a real one, so this treatment is not currently recommended by doctors.
When to get medical help urgently
Croup is often only a mild illness, but it can become serious quickly.
Get medical help immediately if you notice any of the following:
- your child has difficulty breathing;
- your child has noisy breathing when at rest;
- the effort of breathing is tiring your child;
- your child has a high temperature and starts dribbling;
- your child cannot swallow;
- your child becomes pale or blue (which usually happens after a coughing spell);
- your child becomes floppy;
- you notice your child’s breastbone being sucked right back;
- your child becomes restless, distressed, irritable and/or delirious; or
- you are worried or concerned for any reason.
Make sure that you have the phone number of an after-hours doctor service at hand. In severe cases, where breathing difficulties may be life-threatening, dial 000 for emergency treatment.
