ObjectivesTo evaluate the efficacy and safety of tamsulosin and Hachimijiogan or Ryutanshakanto in patients with lower urinary tract symptoms due to benign prostatic hyperplasia.MethodsA prospective, randomized, double‐blind method was used to determine the efficacy and safety of the combination or placebo at baseline and 4, 8, and 12 weeks of study. The International Prostate Symptom Score, quality of life index, complete voiding diary, and National Institutes of Health‐Chronic Prostatitis Symptom Index were studied. Uroflowmetery and postvoid residual urine volume were measured and compared. Laboratory tests including prostate‐specific antigen were performed.ResultsIn all groups, International Prostate Symptom Score and quality of life showed improvement, but no significant differences were shown among the groups. Prostate volume increased after treatment, and uroflowmetric parameters showed improvements after treatment without significance among the three groups. The total score of the National Institutes of Health‐Chronic Prostatitis Symptom Index showed a significant improvement in all groups, without significant differences among the groups. Only the pain sub‐score of the National Institutes of Health‐Chronic Prostatitis Symptom Index showed a significant decrease in the tamsulosin with Ryutanshakanto group compared to the control group. A total of 11 adverse reactions occurred, but they were mild and not related to the study drugs.ConclusionRyutanshakanto can provide pain relief in patients with chronic prostatitis and chronic pelvic pain syndrome. If more research is conducted, Hachimijiogan and Ryutanshakanto may be applied as add‐on treatments in patients with storage symptoms with alpha‐blocker monotherapy.