Asthma and Allergy > Asthma

Asthma

Asthma is a chronic disease that affects your airways, which carry air in and out of your lungs. An estimated 20 million people in the United States have asthma.

Asthma is caused by inflammation in the lung’s airways. Inflammation causes the airway to swell, produce mucus and tighten the muscles that surround the airways. All this makes the airways narrow, making it harder to breath. Inflammation may permanently change the structure of the airways over time, similar to a scar.

Asthma cannot be cured, but it can be controlled, so that symptoms are infrequent. It is important to learn what triggers your asthma symptoms and how to avoid them.