Asthma is a chronic disease that affects the airways, causing inflammation and narrowing. During an asthma attack, the muscles around the airways tighten, less air can flow through, and more mucus is produced, further narrowing the airways. Asthma attacks can range from mild to life-threatening. With effective management including medication and avoiding triggers, asthma can usually be controlled to allow normal activities. However, uncontrolled asthma can lead to missed school/work and inability to participate in some activities.