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Updated January 25, 2014

Definition: Asthma is a medical condition that causes narrowing of the small airways in the lungs. Typically, asthma patients develop wheezing and have increased mucous production in their lungs. Asthma patients can have episodes of increased shortness of breath, often triggered by allergic reactions. Asthma sufferers often have the disease for many years, and the episodes of shortness of breath can be life-threatening.

Pronunciation: AS - mah

Examples: The episodes of shortness of breath associated with asthma are called bronchospasms.

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