If the cough is due to chronic obstructive pulmonary disease (COPD) or chronic bronchitis, the first step is to stop smoking and avoid infection. When the cough is severe, you can use cough suppressants, such as compound licorice tablets and powerful lozenges. If the patient cannot cough up phlegm, expectorant medications such as Mucosolvan can be used. 2. Perform active anti-infection, promote sputum drainage, and interventional or surgical treatment if necessary.