Patient information from BMJ

Bronchiolitis

Last published:Dec 06, 2021

Bronchiolitis is a common infection affecting the lungs of babies and very young children. It can make them wheezy and affect their breathing. It isn't usually serious and most children recover at home. But some children need hospital care.

You can use our information to talk with your doctor and decide which treatments are best for your child.

What is bronchiolitis?

Bronchiolitis is an illness caused by an infection in the small tubes inside a child's lungs. These tubes are called bronchioles.

When a child has bronchiolitis the walls of these tubes become swollen and the tubes fill with mucus. This makes it harder for the child to breathe. Bronchiolitis is usually caused by a virus called the respiratory syncytial virus (RSV).

Bronchiolitis mainly affects children under 2 years old. Around 1 in every 30 babies are diagnosed with the illness before their first birthday.

Like colds and flu, bronchiolitis follows a seasonal pattern, with most infections happening in the late autumn, winter, and early spring.

What are the symptoms?

The symptoms of bronchiolitis aren't severe for most children. Your child might have a heavy cold, runny nose, wheezing, and a cough. They might also have a mild fever.

But some children have more serious problems with their breathing. Your child should see a doctor or be taken to hospital straight away if they:

• have bluish lips or skin

• breathe fast or have flaring nostrils

• have bad wheezing or a crackly-sounding chest

• need to make a big effort to breathe, or stop breathing for a few seconds

• struggle to feed or drink.

What treatments work?

Treatments for bronchiolitis

Most children with bronchiolitis can be looked after at home. If your child is usually healthy your doctor might just suggest you give them plenty of fluids and let them rest.

If your child is in pain or has a fever you can give them paracetamol syrup (for example, Calpol).

Doctors sometimes prescribe a medicine called a corticosteroid (for example, prednisolone) to children with bronchiolitis. But it's not clear from research whether these medicines make a difference, and they are currently not recommended. The same is true for medicines called bronchodilators.

They are most likely to be helpful if a child is over 1 year old and has had wheezing before or has an increased chance of having asthma (for example, if one of the child's parents has asthma).

You should take your child back to the doctor if he or she can't drink enough or they start to have a harder time breathing.

If your child has difficulty breathing, they might need oxygen treatment in hospital. This involves giving them extra oxygen through a tube that's put in their nose, or through a type of hood that goes over their head.

If your child still can't get enough oxygen he or she might need to be put on a ventilating machine that breathes for them. But most children don't need a ventilating machine.

If your child can't drink enough he or she might need to be given fluids through a drip (also called an intravenous infusion or IV). Your child might also be given food through a tube passed through the mouth and into the stomach.

Children who are very ill with bronchiolitis are sometimes treated with an antiviral medicine (a type of drug that fights viruses).

This type of medicine is also given to some children who have a high chance of becoming very ill from bronchiolitis: for example, if they have another illness that affects their breathing or a weak immune system.

But there's not much good research about whether antivirals can help, and they can have side effects.

Treatments to prevent bronchiolitis

Babies who were born early (prematurely) or with heart problems, or who have a lung condition or a very weak immune system are sometimes given a medicine called palivizumab to help prevent bronchiolitis during the months of the year when it is most common.

Palivizumab is a medicine that helps the body fight off the virus that usually causes bronchiolitis. During peak bronchiolitis season these children might have the medicine once a month, for up to five months.

What will happen to my child?

Most young children with bronchiolitis get better at home, usually within a few days. But even if your child needs hospital treatment they'll usually only need to stay in hospital until doctors can make sure their breathing is OK and they can eat and drink enough.

Children who have had bronchiolitis - particularly if they had to be treated in hospital - are more likely than other children to have episodes of wheezing later on. However, many children outgrow this wheezing by the time they are about 13 years old.