Disease summary

Asthma is a chronic disease that affects the airways and the lungs. In people with asthma, the passageways into the lungs become inflamed over time, making it hard to breathe. The inflammation worsens when you come in contact with “triggers” like allergens or exercise. Poorly controlled asthma can result in increased emergency room (ER) visits, hospitalizations, and missed time from work or school. The diagnosis of asthma is based on a combination of history of symptoms, physical examination, and lung function tests. Asthma is classified by disease severity; these classifications are used to help guide proper treatment and disease management.

An estimated 25 million people in the United States suffer from asthma, approximately 8% of the population. Additionally, there are about 1.7 million ER visits related to asthma each year. While there is currently no cure, symptoms can be well controlled to reduce the impact on your daily life and to prevent further airway damage.

Asthma classifications

Common symptoms of asthma

The most common symptom of asthma is wheezing. Other symptoms can include difficulty breathing, chest tightness or pain, coughing, and trouble sleeping. Symptoms often occur during asthma attacks. An asthma attack can be triggered by dust, pet dander, or pollen. Factors in the environment like air pollution, smoke, and changes in the weather can also cause an attack, as can an increase in physical activity.