Asthma

Chronic respiratory disease characterized by airway hyper-reactive, ie an increase in the constrictor response bronco-bronchial tree. Airways finest casual and reversible decrease in size by its smooth muscle contracting or spreading of the mucosa inflamed and produce mucus, usually in response to one or more factors such as exposure to an inappropriate environment (cold, wet or allergen), exercise or effort in hyper-reactive patients, or emotional stress. This narrowing causes obstruction and therefore difficult to move the air that is largely reversible, unlike chronic bronchitis where there is little reversibility(ASMA)