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What is an asthma symptom, episode, or attack?

Asthma is a disease in your body's airways, which are the paths that carry air to your lungs.  Asthma symptoms may include coughing, chest tightness, wheezing, and trouble breathing.  When people have only some coughing, wheezing, or trouble breathing, they call it having asthma symptoms, an asthma episode, or an asthma exacerbation.  When asthma symptoms keep getting worse or are suddenly very severe, it is an asthma attack.

During an asthma episode or attack, the sides of the airways in your lungs swell, and the airways shrink.  Less air gets in and out of your lungs, and mucus clogs up the airways even more.  Severe asthma attacks can be life-threatening.

To learn more about what happens during an asthma attack, read frequent questions from CDC or visit the American Lung Association's website.