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Asthma (say: AZ-muh) is a condition that affects a person's breathing. Inside the lungs are airways called breathing tubes or bronchial (say: BRONG-kee-ul) tubes. With asthma, some of the smallest tubes can swell and narrow, making it harder for air to get through.

Let's talk about breathing. When you breathe in, air enters your nose or mouth, then goes to the windpipe, also called the trachea (say: TRAY-kee-uh). From there, the air travels into the lungs through the breathing tubes. These airways divide like branches of a tree and get smaller and smaller until they reach the end of the line.

At the end of the smallest airways are the alveoli (say: al-VEE-oh-lye), tiny sacs deep in the lungs. That's where your lungs take oxygen out of the air and move it into your blood — an important step because every part of your body needs oxygen to keep working like it should. The whole process goes in reverse when you exhale, sending carbon dioxide out of your body.

A kid with asthma can have trouble breathing because the airways are sensitive. They work normally sometimes, but other times they might swell and narrow. So breathing gets harder because the tubes close in a little bit, like a straw that's being squeezed. The swollen airways can make extra mucus, which makes things pretty sticky, so that can get in the way, too.

A kid with asthma may wheeze (make a whistling sound), cough, and feel tightness in the chest. An asthma flare-up can get worse if a kid doesn't use asthma medicine. After an asthma flare-up, the airways almost always return to the way they were before, although it can take several days.

Who Gets Asthma?

No one really knows why one person's airways are more sensitive than another person's, but we do know that asthma runs in families. That means if a kid has asthma, he or she might have a parent, sibling, uncle, or other relative who has asthma or had it as a kid.

What Causes an Asthma Flare-Up?

Anything that causes an asthma flare-up (attack) is called an asthma trigger. Different kids have different triggers. Common triggers include:

  • allergens, such as dust, pollen, furry animals, and mold
  • irritants, such as cigarette smoke, perfume, and chalk dust
  • infections, like a cold or the flu

How Is Asthma Treated?

One way to treat asthma is for the person to avoid triggers, like furry animals or dust. But it's not always possible to avoid triggers, so most kids who have asthma also take medicine.

Not every kid's asthma is the same, so there are different kinds of medicines for treating it. The doctor will think about what causes the asthma flare-ups, how fast the flare-ups happen, and how serious they are. Then he or she will decide on the best kind of treatment.

The doctor also can write down an asthma action plan to help a kid remember which medicines to use and when. Kids with asthma might use a peak flow meter to get an idea of how well they are breathing that day and whether they need to take any medicine.

A kid who knows in advance that he or she will be around allergens or other triggers may need to take medicine ahead of time that will keep the airways open. And kids who have exercise-induced asthma can take medicine before exercising so they'll be able to finish a race or game.

One kind of asthma medicine is called quick-relief (or fast-acting) medicine. It works fast to help open a kid's airways so he or she can breathe again.

Another kind of asthma medicine is called long-term control medicine (also called controller or maintenance medicine). It's a daily medicine that's designed to keep flare-ups from happening.

Asthma medicine often is taken through an inhaler (say: in-HAY-lur), a plastic tube that holds a container of medicine. A kid holds the inhaler up to his or her mouth and breathes in. The medicine comes out in a mist that goes into the lungs. The medicine in the mist relaxes the airways, so the person can breathe easier.

Use a Spacer

Most kids with asthma use an inhaler with something called a spacer. A spacer attaches to the inhaler and holds the mist in one place, between the inhaler and the kid's mouth. It lets the kid breathe in when he or she is ready, so it's easier to inhale all the medication into the lungs.

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Kids also might take pills or liquid medicine to control asthma. In rare cases, they might get an injection (shot) at the doctor's office. Whatever medicine the kid takes, the goal is always the same: to keep asthma under control so triggers don't create problems.

A lot of kids find their asthma goes away or becomes less serious as they get older. Some doctors think this happens because the airways grow wider as a kid grows up and gets bigger. With more room in the airways, the air has an easier time getting in and out.

Some people do have asthma as adults, but it doesn't have to slow them down. Some top athletes manage their asthma while still competing at professional and Olympic levels.

Reviewed by: Rupal Christine Gupta, MDDate reviewed: March 2015
Originally reviewed by: Elana Pearl Ben-Joseph, MD, and Nicole Green, MD