Objective To investigate the clinical effect and safety of Yiqing Capsule （Herbal capsule for acne） in the treatment of acne vulgaris.Methods A randomized controlled open trial was conducted

and totally 144 acne vulgaris patients were randomized into Yiqing group and control group with 72 cases in each. The former received the treatment with Yiqing Capsule and calamine lotion for external use

while the latter received the treatment with Viaminati Capsule and calamine lotion for external use for 28 days. Those who were cured and markedly relieved were followed up for 6 months. The symptoms and signs before treatment

1

2

and 4 weeks after treatment were scored

the 6-month follow-up was carried out

and the recurrence was recorded to evaluate the clinical effect. The untoward effect in the duration of treatment was observed.Results A total of 129 cases finished the treatment

68 in the Yiqing group and 61 in the control group. At the end of the first and second week of treatment

the effective rate of the Yiqing group was 42.65% and 75.00% respectively

that of the control group was 14.75% and 31.15% respectively

with a statistical difference between groups（P<0.05）. At the end of the fourth week of treatment

the effective rate of the Yiqing group was 94.12% and that of the control group 90.16% respectively

without statistical difference between （P>0.05）. At the end of the first and fourth week of treatment

the symptom and sign score of the Yiqing group was significantly lower than that of the control group （P<0.05）. The incidence of untoward effect of the control group was significantly higher than that of the Yiqing group （P<0.05）.Conclusion Yiqing Capsule is effective for acne vulgaris with a quicker effect and lower incidence of untoward effect than Viaminati Capsule.