Asthma is a lung condition that causes the airways to become swollen and inflamed periodically and to produce excess mucous. This swelling, inflammation, and extra mucous can make it more difficult to breathe, or can cause wheezing or coughing. In asthma, the airways usually don’t remain swollen and inflamed all the time. Instead, the airways only swell and become inflamed at certain times. When this happens, it is called an asthma attack. Asthma attacks can be relatively mild, or they can be much more severe or even life threatening.
Asthma often begins during childhood, but it can affect people of any age. It may be relatively mild, causing only minor nuisance, or very serious, interfering with day-to-day activities.