Bronchial asthma, do you know it? When you have recurrent cough, phlegm, chest tightness and shortness of breath, do not just think you have bronchitis. Do not take it upon yourself to apply anti-infective drugs as soon as coughing and phlegm appear. Bronchial asthma is a chronic airway inflammatory disease. When you have repeated episodes of wheezing, dyspnea, chest tightness or coughing, and the episodes are mostly regular (such as when the environment changes, after cold and flu, after exercise, etc.) and seasonal, and the croup (commonly known as whistling sound) can be heard during the episodes, and when anti-infection treatment is ineffective, or can be relieved after rest or medication, then you must think that you may have bronchial asthma. When you find yourself in the above situation, you must go to a regular hospital to perform the most basic tests such as chest CT, lung function, NO breath test and allergens. Once you have been diagnosed with bronchial asthma, you must get regular treatment under the guidance of your doctor and review your lung function regularly.