The immune system and immune response are at the heart of the symptoms that develop in asthma. In asthma, the muscles lining the airways are very sensitive and overreact to substances or events, known as triggers, that other people tolerate without problem.
Your asthma symptoms are caused by 3 main physiological processes, and treatment is targeted to address all of them:
- Tightening of the muscles lining the airways: This contraction or tightening of the bronchial smooth muscles is called bronchospasm or bronchoconstriction. As these muscles tighten around the outside of your bronchial tubes, causing narrowing, it becomes more difficult to move air through the lung. When this occurs, you may notice shortness of breath, chest tightness or wheezing.
- Mucus production: In addition to the bronchoconstriction, airways of the lung produce an increased amount of mucus. This can lead to mucus plugging and further narrowing of the airways, making symptoms worse.
- Inflammation: The inside of the airways become swollen and inflamed. This swelling even further decreases airflow and makes it more difficult to breathe. The inflammation generally occurs later in an asthma attack.
These 3 processes are what is going on in your lung during an asthma attack. If these 3 abnormalities are not treated over long periods of time, airway remodeling may lead to chronic lung damage.
Sources:
Asthma. In Chest Medicine: Essentials Of Pulmonary And Critical Care Medicine. Editors: Ronald B. George, Richard W. Light, Richard A. Matthay, Michael A. Matthay. May 2005, 5th edition.
Centers for Disease Control and Prevention. Consumer Information. Accessed: April 20, 2009. Asthma: General Information
National Heart, Lung, and Blood Institute. Accessed: April 20, 2009. Expert Panel Report 3 (EPR3): Guidelines for the Diagnosis and Management of Asthma
