A randomized controlled study to evaluate the efficacy of tamsulosin monotherapy and it combination with mirabegron on patients with overactive bladder induced by benign prostatic hyperplasia

INTERVENTION: Harnal (0.2mg daily) for 8weeks Batanis (50mg daily) and Harnal (0.2mg daily) for 8weeks. CONDITION: Men with overactive bladder induced by benign prostatic hyperplasia PRIMARY OUTCOME: Change in total score of OABSS at 8 weeks SECONDARY OUTCOME: Changes in total score of IPSS, QOL index and Qmax at 8 weeks INCLUSION CRITERIA: 1. Age > or = 50 years‐old 2. Patients with benign prostatic hyperplasiua who are treated by tamsulosin at least for 8 weeks 3. OABSS (Q3, urgency score) > or = 2, OABSS (total score) > or = 3