ABSTRACT

Bronchial asthma Bronchial asthma is a condition characterized by difficulty in breathing. It occurs when extrinsic factors (allergens) or intrinsic factors (nonimmunological conditions) cause various mediators, including histamine and the leukotrienes, to be released from mast cells and circulating basophils. This results in relatively rapid contraction of the smooth muscle that surrounds the airways, accompanied by a slower secretion of thick, tenacious mucus and edema of the respiratory mucosa. Characterized by wheezing, coughing, shortness of breath, and tightness in the chest, bronchial asthma is reversible. It is a complex disease in which airway obstruction is responsible for the clinical manifestations; however, bronchial hyperresponsiveness and underlying inflammation are also characteristic features. Treatment involves the use of bronchial dilators (the most common is theophylline) as well as various adrenergic amines and anticholinergic agents that reverse the acute attack (bronchoconstriction) or prevent bronchospasm from occurring. In addition, anti-inflammatory agents such as aerosol corticosteroids and cromolyn sodium modify the airway inflammation and reduce bronchial hyperresponsiveness.1