Coughing as soon as you smoke can be mild or severe, and there are many reasons for it, which are commonly found in chronic pharyngitis, chronic bronchitis, chronic obstructive pulmonary disease, lung cancer, and so on. 1. Chronic pharyngitis: Chronic pharyngitis is a chronic diffuse inflammation of the pharyngeal mucosa and submucosal tissues, which often has a very long course and recurs over a long period of time. Smoking can stimulate the pharyngeal mucosa, aggravate the inflammatory response, causing patients to cough and cough phlegm aggravation. 2. Chronic bronchitis: chronic bronchitis is a chronic non-specific inflammation of the bronchial mucosa and surrounding tissues, smoking will stimulate the bronchial secretion increase, damage to the organ mucosal epithelium, aggravate cough and phlegm symptoms. 3. Chronic Obstructive Pulmonary Disease (COPD): COPD is diagnosed when patients with chronic bronchitis have persistent airflow limitation on pulmonary function tests. Smoking will further aggravate airway damage, accelerate the development of the disease, and aggravate the symptoms of coughing and sputum. 4. Lung cancer: there is clear evidence that smoking is closely related to lung cancer, and the possibility of lung cancer should be highly suspected if there is a long history of smoking and unexplained severe cough. If the symptoms of coughing after smoking appear, it is recommended that the patient go to the hospital in time to find out the cause of the disease, and carry out standardized treatment under the guidance of the doctor. In addition, smoking is harmful to health, so it is recommended to quit smoking as soon as possible.