Asthma is a common and chronic inflammatory condition of the airways whose cause is not completely understood. As a result of inflammation the airways are hyperrespensive and they narrow easily in response to a wide range of stimuli .This may result in coughing, wheezing, Chest, tightness and Shortness of breath and these symptoms are often worse at night. Narrowing of the airways is usually reversible , but in some patients with chronic asthma the inflammation may lead to irreversible, but in some patients with chronic asthma the inflammation may lead to irreversible airflow obstruction characteristic Pathological features include the presence in the airways of inflammatory cells, plasma exudation, oedema, Smooth muscle hypertrophy, mucus plugging and Shedding of the epithelium.