What is Asthma?

Asthma is a chronic (long-term) lung dis­ease that inflames and narrows the air­ways. This makes the airways swollen and very sensitive. They tend to react strongly to certain substances that are breathed in.

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What is Asthma
(National Heart, Lung
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When the airways react, the muscles around them tighten. This causes the airways to nar­row, and less air flows to your lungs. The swell­ing also can worsen, making the airways even narrower. Cells in the airways may make more mucus than normal. (Mucus is a sticky, thick liquid that can further narrow your airways.)

Symptoms may include:

  • wheezing (a whistling sound when you breathe)
  • chest tightness
  • shortness of breath
  • coughing

Symptoms can happen each time the airways are irritated.

Sometimes symptoms are mild and go away on their own or after minimal treatment with an asthma medicine. Other times, symptoms con­tinue to get worse. When symptoms get more intense and/or additional symptoms occur, this is an asthma attack.

It’s important to treat symptoms when you first notice them.  This will help prevent the symp­toms from worsening and causing a severe asth­ma attack.

Severe asthma attacks may require emergency care, and they can cause death.


The exact cause of asthma isn’t known. Researchers think a combination of factors (family genes and certain environmental exposures) interact to cause asthma. Different factors may be more likely to cause asthma in some people than in others.   Most, but not all, people who have asthma have allergies.


Asthma is a long-term disease that can’t be cured. It is treated with two types of medicines: long-term control and quick-relief medicines. Long-term control medicines help reduce air­way inflammation and prevent asthma symp­toms. Quick-relief, or “rescue,” medicines relieve asthma symptoms when they flare up.

The goal of asthma treatment is to control the disease and prevent asthma attacks. Good asth­ma control will:

  • Prevent chronic and troublesome symptoms, such as coughing and shortness of breath
  • Reduce your need for quick-relief medicines
  • Help you maintain good lung function
  • Let you maintain your normal activity levels and sleep through the night
  • Prevent asthma attacks that could result in your going to the emergency room or being admitted to the hospital for treatment