Medical Specialties: Allergy/immunology, Emergency medicine, Family practice, Pulmonology

Clinical Definition

Asthma is a chronic inflammatory disease of the lungs characterized by increased airway reactivity in response to certain stimuli. During an asthma exacerbation, constriction of the smooth muscle of the bronchi, increased mucus production and mucosal edema occur, which creates the clinical presentation of respiratory distress.  

In Our Own Words

Asthma is a chronic medical condition affecting the lungs. People who have asthma have airways that are sensitive to certain things that generally don’t bother other people. Various stimuli, known as triggers, can cause an asthma attack. Common triggers include dust, smoke, exercise and cold weather. 


During an asthma attack, the airways tighten, and inflammation or swelling occurs. The tightening and swelling makes the airways narrow. There is also an increase in mucus production. This combination of factors makes getting air in and out of the lungs difficult. 

Relevant Conditions
  • COPD
  • Bronchitis
Common Types
  • Exercise induced asthma
  • Occupational asthma
Side Effects
  • Shortness of Breath
  • Wheezing
  • Coughing
Share this article
  • Cleveland Clinic. “Asthma Overview.” Accessed September 2013.
  • Asthma and Allergy Foundation of America. “Asthma Basics.” Accessed September 2013.
  • Cleveland Clinic. “Asthma Symptoms.” Accessed September 2013.
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