Cough syrup is mostly used in clinical upper respiratory tract infections caused by coughing and coughing up phlegm, the main effect is to relieve cough and resolve phlegm, suitable for bronchodilatation, bronchial asthma and cough, phlegm and upper respiratory tract infections caused by the application. Cough is a defensive reflex when the respiratory system is stimulated, mild cough can clear the phlegm and foreign matter in the trachea, and can be relieved naturally without the need to take cough syrup. However, if the cough is frequent, intense, accompanied by coughing phlegm, cough pus sputum, cough yellow mucus sputum, then you should apply a certain amount of cough syrup, to play the role of anti-inflammatory, cough, cough, cough, phlegm, asthma effect. Commonly used cough syrup clinically based on Chinese medicine cough, there are half a summer cough syrup, loquat cough syrup, cough syrup, Sichuan shellfish cough syrup, etc., have a moisturizing lung phlegm, clearing heat and detoxification effect. In addition, there are western medicine cough syrup, ephedrine and ephedrine as the main asthma, cough effect, advocating the application of Chinese medicine cough syrup for anti-inflammatory, cough, phlegm.