What Asthma Looks Like

If you have asthma, the airways into your lungs can become chronically narrow and inflamed. Although you may feel fine, your lung capacity—the amount of air you can hold in your lungs—can be diminished. If you encounter a trigger—such as allergies, infections, exercise, and environmental factors such as pollution and secondhand smoke—airways can tighten even further. During these asthma attacks, the narrow bronchial tubes make it difficult to breathe.

This can lead to symptoms such as coughing, wheezing, and shortness of breath. This image from our A–Z Health Library illustrates the difference between normal bronchial tubes and those narrowed due to asthma.