The word asthma originates from an ancient Greek word meaning panting. Essentially, asthma is an inflammatory lung condition that makes it difficult to breathe properly. When any person inhales, the air travels through the following structures:
Asthma is a chronic condition in which these airways undergo changes when stimulated by allergens or other environmental triggers. Such changes appear to be two specific responses:
These actions in the airway cause coughing, wheezing, and shortness of breath (dyspnea), the classic symptoms of asthma.
In the hyperreactive response, smooth muscles in the airways constrict and narrow excessively in response to inhaled allergens or other irritants. Airways in everyone's lungs respond by constricting when exposed to allergens or irritants but there are major differences in the hyperreactive response that occurs in people with asthma:
The hyperreactive stage is followed by the inflammatory response, which generally contributes to asthma in the following way:
Inflammation appears to be present in the lungs of all patients with asthma, even those with mild cases, and plays a key role in all forms of the disease.
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