| Version | Summary | Created by | Modification | Content Size | Created at | Operation |
|---|---|---|---|---|---|---|
| 1 | Catherine Yang | + 688 word(s) | 688 | 2020-12-15 07:15:20 |
Asthma is a breathing disorder characterized by inflammation of the airways and recurrent episodes of breathing difficulty. These episodes, sometimes referred to as asthma attacks, are triggered by irritation of the inflamed airways. In allergic asthma, the attacks occur when substances known as allergens are inhaled, causing an allergic reaction. Allergens are harmless substances that the body's immune system mistakenly reacts to as though they are harmful. Common allergens include pollen, dust, animal dander, and mold. The immune response leads to the symptoms of asthma. Allergic asthma is the most common form of the disorder.