a condition of the lungs in which there is widespread narrowing of airways, varying over short periods of time either spontaneously or as a result of treatment, due in varying degrees to contraction (spasm) of smooth muscle, edema of the mucosa, and mucus in the lumen of the bronchi and bronchioles; these changes are caused by the local release of spasmogens and vasoactive substances (e.g., histamine, or certain leukotrienes or prostaglandins) in the course of an allergic process, a chronic respiratory disease characterized by paroxysmal attacks of dysphnea with wheezing due to constriction of the smaller airways due to smooth muscle spasm