【Abstract】Objective To study the efficacy and safety of San’ao tablet in treating cough after infection. MethodsA total of 300 patients with infectious respiratory irritation cough in our hospital from January 2016 to December 2018 were enrolled as subjects. According to the conditions, 150 patients with viral infectious respiratory tract irritation were divided into the observation group A and the control group A with 75 patients in each group. The control group A was treated with conventional treatment, and the observation group A were treated with San’ao tablets and the basis of conventional treatment. Another 150 patients with bacterial infections respiratory irritation cough were divided into the observation group B and the control group B with 75 cases in each group. The control group B were treated with conventional treatment, and the group B were treated with San’ao tablets the basis of conventional treatment. The respiratory symptoms scores, symptoms as well as signs duration, comparison of cough symptoms, total treatment efficacy and safety before and after treatment were compared in those four groups. The bacterial clearance rate after treatment in the observation group B and the control group B were compared. Results The total effective rate of treatment in the observation group A was 9333%, which was significantly higher than that in the control group A (7333%)（P＜005）. The total effective rate of treatment in the observation group B was 9600%, which was significantly higher than that in the control group B (7067%) (P＜005). The score of respiratory symptoms in patients with observation group A and group B were significantly lower than those in control group A and group B after treatment (P＜005). The adverse reaction rates of the control group A and the control group B were higher than those of the observation group A and the observation group B (P＞005). The total bacterial clearance rate of the observation group B was 8667%, which was significantly higher than that of the control group B (7600%) (P＜005).Conclusions San’ao tablets combined with conventional treatment can effectively improve the respiratory symptoms in patients with infectious respiratory irritating cough with good efficacy and safety, and can effectively improve the bacterial clearance rate.