Cough variant asthma is also known as allergic asthma, cryptogenic asthma, and cough asthma. It is a specific type of asthma with chronic cough as the only manifestation, and its prevalence in children is about 0.77% to 5.0%. The persistent inflammation of the respiratory tract and the swelling of the bronchial epithelium in children with asthma make the excitation threshold of the subendothelial stimulus receptors in the airways lower than normal, so that the sensitivity to various external stimuli is increased and asthma occurs at the slightest stimulus; moreover, asthma is difficult to cure. Cough variant asthma is characterized by: 1. persistent or recurrent coughing attacks for more than one month, often occurring at night or in the early morning, aggravated by exercise, with little sputum; 2. laboratory or other tests showing no obvious signs of infection or ineffective after long-term antibiotic treatment; 3. use of bronchodilators to reduce attacks; 4. personal history of allergies or family history of allergies; 5. Asthma attacks are triggered by exercise, cold air, allergens or viral infections; 6. Asthma is seasonal, mostly seen in spring and autumn and recurrent; 7. Chest X-ray shows normal or increased lung texture but no other organic changes. If the child has the above characteristics and other related organic diseases are excluded, cough variant asthma should be suspected and the child should be taken to an asthma clinic for detailed examination. The treatment of cough variant asthma is mainly based on anti-allergic drugs: fenagin, ketotifen; cough suppressants such as aminophylline and methotrexate; preventive drugs such as bronchitis vaccine tablets can also be used. For individual with the above drugs is not effective can be treated with glucocorticoids, such as: oral prednisone, or inhalation of Pulmicort aerosol, Bacodone aerosol, generally asthma will improve, cough disappears.