Asthma is a lung disease that can make it hard to breathe. Children are more likely to have asthma than adults, but they can sometimes “outgrow” it. Asthma can also start for the first time in adults, and it can be a lasting problem.
When you breathe, air travels through your nose and mouth into your lungs. It travels though airways that branch into smaller and smaller branches. In people with asthma, the airways tighten and narrow during an attack, making it hard for air to get in and out of the lungs. Also, the lining of the airways gets irritated and makes mucus, which further blocks the flow of air.