What is Asthma?
		Asthma affects the small breathing tubes in the lung called bronchioles. These small breathing tubes are very sensitive. Allergens and irritants can cause these tubes to become swollen and narrow. When asthma is triggered, the lining of the breathing tubes becomes red and inflamed and makes extra mucus. The muscle surrounding the breathing tubes tightens up. It is difficult to move air out through these narrow passages. As air whistles through these tight spaces, a high pitched musical sound is made. This sound is called wheezing. The hard work of moving air through these narrow passages can make the chest feel tight. Asthma can cause coughing, wheezing, chest tightness, and/or difficulty breathing. These symptoms may be present only sometimes or they may be present most of the time.
		Introduction Understanding Asthma Treatment of Asthma Living with Asthma Site design and illustrations by Green Island Graphics