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Health Fact Sheets


Asthma is a serious, sometimes life-threatening respiratory disease that affects the quality of life for millions of Americans. Although there is no cure for asthma yet, asthma can be controlled through medical treatment and management of environmental triggers.


Asthma is sometimes triggered by an allergic reaction to substances commonly breathed in through the air, such as animal dander, pollen, mold, tobacco smoke, or dust mite and cockroach waste products. Other triggers that can cause asthma attacks are strong odors, changes in the weather, viral or sinus infections, exercise, medications, and food.  These, and other substances, are known as allergens.

Airways are the paths that carry air to the lungs. As the air moves through the lungs, the airways become smaller, like branches of a tree. During an attack, the sides of the airways in your lungs become inflamed and swollen. Muscles around the airways tighten, and less air passes in and out of the lungs. Excess mucus forms in the airways, clogging them even more. The attack, also called an episode, can include coughing, chest tightness, wheezing, and trouble breathing.

You can control your asthma and avoid an attack by taking your medicine as prescribed and avoiding the triggers that can cause an attack. It’s just as important that you remove the triggers in your environment that you know make your asthma worse.

Medicine for asthma is different for each person. It can be inhaled or taken as a pill and comes in two types—quick-relief and long-term control. Quick-relief medicines control the symptoms of an asthma attack. Long-term control medicines help you have fewer and milder attacks, but they don’t help you if you’re having an attack.

Without treatment, such as inhaled corticosteroids to reduce the inflammation, asthma attacks can be deadly.

Asthma Statistics

  • Asthma leads to 2 million emergency room visits and 5,000 deaths per year in the U.S.  
  • Asthma accounts for approximately 14.5 million missed work days for adults annually.  
  • 20.3 million Americans report having asthma.

Asthma Related Websites