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Basic Information About Asthma

Here is a primer on asthma, including how it’s diagnosed.

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Asthma is a potentially life-threatening disease marked by wheezing, shortness of breath, chest tightness and coughing. If you think you or your child has asthma, it’s important to get it diagnosed and learn how to control it.

What is asthma?

Asthma is a chronic lung disease that often begins in childhood. People with asthma have inflamed airways, which can be very sensitive to certain triggers like pollen and cigarette smoke. When something irritates the airways, the muscles around them tighten, narrowing the space. The swelling can become worse, too. If mucus develops, the airways can narrow even further.

You can help control your asthma by taking these steps:

  • Work with your doctor to develop an asthma action plan.
  • Take your medicines exactly as prescribed.
  • Learn the warning signs of an asthma attack and what to do if they occur.
  • Avoid things that trigger your asthma attacks.

What are the symptoms of asthma?

Symptoms of asthma may include:

  • Wheezing (a whistling sound when you breathe)
  • Shortness of breath
  • Coughing, especially at night or in the early morning
  • Tightness in the chest

Who is at risk?

If one of your parents has asthma, you are more likely to have it. Most people with asthma also have allergies. Boys with asthma outnumber girls, but the gender difference disappears in adulthood. Researchers believe that genetic and environmental factors can interact and cause asthma. Some childhood respiratory infections and exposure to certain airborne allergens or viral infections in early childhood may contribute to asthma. But the exact cause of asthma remains a mystery.

What are the most common triggers of asthma symptoms?

A trigger is something that causes your asthma symptoms to flare up. Triggers can be from indoor or outdoor sources and may be an irritant or allergen. The most common triggers are:

  • Airborne irritants such pollution
  • Tobacco smoke
  • Respiratory infections, such as colds
  • Physical exercise
  • Psychological stress
  • Certain medications

The most common allergens are:

  • Pollen
  • Mold spores
  • Animal dander or hair
  • Dust mites
  • Cockroach remnants
  • Sulfites (a common food preservative)

Diagnosing asthma

If you have not been diagnosed with asthma but have concerns, see your doctor. Your doctor will ask questions about your medical and family histories. To gain a better understanding, he or she will ask you which symptoms you have, when they appear and how much they affect your life. And she will ask whether others in your family also have asthma and allergies.

You will get a physical exam. The doctor will listen to your breathing. He or she will check to see if you have common signs of asthma or allergies. These include wheezing, a runny nose and eczema or other allergic skin conditions.

Expect some medical tests, too. One is a breathing test called spirometry. It gauges how well your lungs are working by measuring how much air you can breathe in and out, and how fast you can exhale. The doctor may give you a second test during the same appointment to see if your breathing improves with asthma medicine.

The doctor may also test you for allergies, since there is a close tie between asthma and allergies.

Don’t delay seeking a diagnosis if you think you or your child has asthma. Asthma is a serious disease. But it is one that you can learn to manage.

National Heart, Lung, and Blood Institute. National asthma education and prevention program expert panel report 3. Guidelines for the diagnosis and management of asthma. Accessed: January 6, 2016.
National Heart, Lung, and Blood Institute. What is asthma? Accessed: January 6, 2016.
Fanta C, Fletcher S. An overview of asthma management. UpToDate. Accessed: January 6, 2016.
American College of Allergy, Asthma and Immunology. Who has asthma and why. Accessed: January 6, 2016.

Last Updated: January 11, 2016