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Asthma in Children


The Manual's Editorial Staff

Reviewed/Revised Sep 2023
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What is asthma?

Asthma is a lung disorder that causes the airways to become narrow, making it hard to breathe. Asthma often starts in childhood, especially before age 5.

With an asthma attack, 2 things happen:

  • The muscles around the airways tighten up

  • The airways swell and fill with thick fluid (mucus)

Because of these things, your child's airways become narrow, making it hard to breathe.

What causes asthma in children?

What are the symptoms of asthma in children?

Common symptoms:

Sometimes, cough is the only symptom.

Go to a hospital emergency department right away or call for emergency medical help (911 in the United States) if your child has any of these warning signs:

  • Trouble breathing, which may include loud wheezing, fast breathing, or gasping

  • Skin that is sweaty and pale

  • Blue lips or fingers from low oxygen in the blood (cyanosis)

How can doctors tell if my child has asthma?

Doctors usually suspect asthma based on your child’s symptoms, especially if asthma or allergies run in your family. Sometimes doctors do tests:

How do doctors treat asthma in children?

To treat mild asthma attacks, doctors will have your child:

  • Use an inhaler to take a fast-acting (rescue) medicine to open the airways

The rescue medicine is a called a bronchodilator. Your child can use a bronchodilator inhaler 1 to 3 times, 20 minutes apart if needed.

To treat severe asthma attacks, go to a hospital emergency department right away or call for emergency medical help (911 in the United States). Doctors will:

  • Give a rescue medicine by inhaler or sometimes in a shot

  • Often give a corticosteroid drug to reduce swelling in your child’s airway

  • Give your child extra oxygen, if needed

  • Sometimes, admit your child to the hospital

  • Rarely, put a breathing tube in your child's windpipe

How can I help my child prevent asthma attacks?

Check your child’s airflow with a peak flow meter. A peak flow meter is a handheld device that measures how fast your child can blow air out. It'll help you know when your child needs medicine.

Some children need to take long-lasting (maintenance) medicines every day. There are many different maintenance medicines. Some are inhalers and some are pills. Your child may need more than one kind of medicine.

Help your child avoid things that trigger asthma attacks:

  • Keep cigarette smoke, strong smells, and fumes out of your house

  • Help your child avoid cold air

  • If needed, have your child use an inhaler before exercising

  • Have your child use a pillow made of man-made materials and a mattress cover to protect against dust mites

  • Wash sheets and blankets in hot water

  • Keep your house clean to avoid dust mites and cockroaches

  • Use a dehumidifier to dry out the air in any damp places like a basement

How does a child take asthma medicine?

Overusing asthma medicines is dangerous. Tell the doctor if your child has to use the medicine more often than prescribed.

A lot of asthma medicine is taken using an inhaler or a nebulizer.


Inhalers (also called metered-dose inhalers) are small, hand-held devices. They are the most common way to take asthma medicines. They turn medicine into a fine spray your child can breathe. An inhaler that has a spacer or holding chamber is easier to use.


Nebulizers are electric or battery-powered machines that turn liquid medicine into a fine spray your child can easily breathe in through a mask.

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