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What Is Asthma?

Asthma (Az-muh) is a chronic disease that affects your airways. The airways are the tubes that carry air in and out of your lungs. If you have asthma, the inside walls of your airways are inflamed (swollen). The inflammation (IN-fla-MAY-shun) makes the airways very sensitive, and they tend to react strongly to things that you are allergic to or find irritating. When the airways react, they get narrower, and less air flows through to your lung tissue. This causes symptoms like wheezing (a whistling sound when you breathe), coughing, chest tightness, and trouble breathing, especially at night and in the early morning.

Asthma cannot be cured, but most people with asthma can control it so that they have few and infrequent symptoms and can live active lives.

When your asthma symptoms become worse than usual, it is called an asthma episode or attack. During an asthma attack, muscles around the airways tighten up, making the airways narrower so less air flows through. Inflammation increases, and the airways become more swollen and even narrower. Cells in the airways may also make more mucus than usual. This extra mucus also narrows the airways. These changes make it harder to breathe.

 Illustration showing anormal airway and an airway in a person with asthma.

Asthma attacks are not all the same—some are worse than others. In a severe asthma attack, the airways can close so much that not enough oxygen gets to vital organs. This condition is a medical emergency. People can die from severe asthma attacks.

So, if you have asthma, you should see your doctor regularly. You will need to learn what things cause your asthma symptoms and how to avoid them. Your doctor will also prescribe medicines to keep your asthma under control.

Taking care of your asthma is an important part of your life. Controlling it means working closely with your doctor to learn what to do, staying away from things that bother your airways, taking medicines as directed by your doctor, and monitoring your asthma so that you can respond quickly to signs of an attack. By controlling your asthma every day, you can prevent serious symptoms and take part in all activities.

If your asthma is not well controlled, you are likely to have symptoms that can make you miss school or work and keep you from doing things you enjoy. Asthma is one of the leading causes of children missing school.

May 2008


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