Objective: To evaluate the efficacy and safety of Shugan Yiyang Capsule (SGYY) in treating psychogenic and mild arteriogenic erectile dysfunction (ED) of Gan stagnation and Shen deficiency Syndrome type with or without blood stasis.Methods: A multi-centered

randomized

double-blinded

placebo-controlled trial in 304 patients was conducted by dividing them into 3 groups

who received respectively SGYY (n = 102)

placebo (n = 101) and Suoyang Bushen capsule (SYBS

n = 101)

1. Og taken three times a day for 4 weeks. Besides

205 patients were arranged in an open-label study and treated with SGYY l.0 g taken three times a day for 4 weeks. The total effective rate

total remarkably effective rate

erection recovery rate tested by penis hardness test ring

time taken for improving erection among groups

as well as therapeutic effect between psychogenic ED group and mild arteriogenic ED group were compared. Adverse reactions related to SGYY were recorded. And a 3-month follow-up study was conducted on 105 cured patients.Results: The trial was completed in 500 patients. The total effective rate and total remarkably effective rate in the SGYY treated double-blinded group were 88.0% and 64.0% respectively

and those in the open-label group 90.5% and 65.0%

respectively

all significantly higher than those in the placebo (21.0%

6.0%) and SYBS groups (60.0%

29.0%)

P<0.01. At the same time

the erection recovery rate and improving time in SGYY group were significantly better than those in other groups (P<0.01). No adverse reactions related to SGYY were found. The successful rate of potency to have intercourse within 3 months was over 80% (100 patients out of the 105 cured patients).Conclusion: SGYY was an effective and safe treatment for patients with psychogenic and mild arteriogenic ED of Gan stagnation and Shen deficiency Syndrome type with or without blood stasis

especially for psychogenic ED patients.