What is Asthma?

Asthma affects nearly 25 million people of all ages and races. An estimated seven million children have asthma. Asthma is a chronic disease caused by inflammation of the airways in the lungs. During an asthma attack the muscles around the airway constrict, the lining of the airway passages swell (airway narrows), and the lungs produce excess mucus. This makes breathing difficult which can lead to symptoms like coughing, wheezing, and shortness of breath.


The symptoms of asthma or an asthma attack can range from minor to severe and vary from person to person. The most common symptoms are coughing, wheezing, shortness of breath, and chest tightness. Other possible symptoms:

  • Frequent cough, especially early morning or at night
  • Coughing or wheezing worsened by a respiratory virus
  • Chest tightness or pain
  • Shortness of breath, coughing, or wheezing after exercise
  • Very rapid breathing
  • Trouble sleeping
  • Fatigue
  • Difficulty talking
  • Feelings of anxiety or panic (due to shortness of breath)
  • Tightened neck or chest muscles, called retractions

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Triggers are irritants specific to an individual and may be different for each person. They can cause swelling of the airway passages and the narrowing of airways making breathing difficult. Triggers do not cause asthma. However, they can induce an asthma attack or episode. Examples of triggers include, but are not limited to:

  • Smoke (Tobacco and Wood)
  • Dust Mites
  • Pet Dander
  • Pest (Cockroaches and Rodents)
  • Mold
  • Air Pollutants (Indoor and Outdoor)
  • Pollen
  • Exercise
  • Extreme Changes in Weather and Cold Air
  • Respiratory Infections (Common Cold or Flu)
  • Strong Odors (chemical fumes, gases, perfumes)
  • Dust
  • Stress or Strong Emotions
  • Food Allergies and Certain Medications
  • Gastroesophageal Reflux Disease (GERD)

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Diagnosis and Tests

Regular checkups with your health care provider that include checking for allergies and testing lung function can help your provider make the right diagnosis. During the checkup your provider will ask questions about symptoms, such as coughing a lot (especially at night or after physical activity), wheezing, or chest tightness.

Tests to Measure Lung Function: Your health care provider may choose to use multiple tests to measure your lung function. The most common tests are spirometry and peak flow:Peak Flow

  • Spirometry, also called a lung function test, is one method to test for a diagnosis of asthma. The spirometer can measure the amount and speed of air you can exhale (breathe out) after taking in a very deep breath.
  • Peak Flow (pictured right), uses a meter to measure how hard you can breathe out. Your health care provider will give you instructions on how to track your measurements and what to do if you have a low peak flow reading.

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Types of Asthma

There are different types of asthma. Your health care provider may diagnose you with unspecified asthma or give details about the type of asthma you have:

1. Exercise-induced asthma (or exercise-induced bronchospasm): this type of asthma can be triggered during exercise or physical activity. The symptoms of exercise-induced asthma generally begin within five to twenty minutes after the start of exercise, or five to ten minutes after exercise has stopped. Having exercise-induced asthma does not mean you should not exercise. With proper treatment and taking precautions you can enjoy physical activities.

2. Nighttime asthma (or nocturnal asthma): asthma symptoms occur at night and can disrupt both the depth and length of sleep.

3. Occupational asthma: certain jobs can increase exposures to asthma triggers. These individuals may experience asthma attacks regularly during their work day.

4. Cough-variant asthma: individuals with cough-variant asthma may only have a chronic cough or severe coughing as their main symptom. Respiratory infections and exercise are common triggers.

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See also: Preventive Measures

Page last updated: April 9, 2017