Objective Detrusor overactivity (DO) is one known cause of overactive bladder (OAB) symptoms in benign prostatic hyperplasia (BPH).In this study,OAB symptoms suggestive of DO in BPH were treated with α1-blocker monotherapy or α1-blocker and antimuscarinics add-on therapy,and the efficacy and safety were assessed.Methods BPH patients who suffered from OAB symptoms for at least 3 month were enrolled in a prospective self-control study from August 2010 to April 2012.The inclusion criteria are total international prostate symptom score (IPSS) ≥8,OAB Symptom Score (OABSS) ≥3,OABSS urgency score ≥2,Postvoid residual volume (PVR) ＜ 100 ml,and maximum urinary flow rate (Qmax) ≥ 5 ml/s.All the patients who met the inclusion criteria were treated with α1-blocker ( tamsulosin 0.2 mg/day or doxazosin 4 mg/day) for 2 weeks.After 2 weeks,patients with no symptomatic improvement ( OABSS≥3) underwent pressure-flow test,and those whose Pdet≥ 40 cm H2O and DO presented more than one time were added antimuscarinics (solifenacin 5 mg/day or tolterodine 4 mg/day) for an additional 2 weeks.OABSS,IPSS,QOL,Qmax and PVR were re-evaluated every 2 weeks.Results Ninety-four cases of BPH/OAB patients met the inclusion criteria and completed 4 weeks treatment.The baseline of total OABSS was 7.0 ± 1.3,IPSS was 17.0 ± 1.7,QOL was 5.0 ±0.7,Qmax was (8.8 ±2.5) ml/s and PVR was (86.0 ± 16.5) ml.After 2 weeks treatment with α1-blocker alone,OABSS was 5.2 ± 0.8,IPSS was 14.2 ± 1.9,QOLwas4.O±0.8,Qmaxwas (11.4±2.4) ml/s and PVR was (67.9±12.9) ml.After another2 weeks treatment with α1-blocker plus antimuscarinics,OABSS was 3.1 ± 0.8,IPSS was 11.1 ± 1.9,QOL was 3.1 ± 0.7,Qmax was ( 10.8 ± 2.4) ml/s and PVR was (71.8 ± 11.9 ) ml.Compared with baseline values,OABSS,IPSS,QOL,Qmax and PVR significantly improved (P ＜ 0.01 ) in α1-blocker monotherapy group and α1-blocker plus antimuscarinic group.The improvement of OABSS,IPSS,QOL scores of α1-blocker plus antimuscarinic group were greater than α1-blocker monotherapy group (p ＜ 0.05 ),while Qmax and PVR showed no differences between the two groups.No acute urinary retention (AUR) was deteted.Conclusion Both of α1-blocker monotherapy and α1-blocker with antimuscarinics add-on therapy can improve OAB symptoms.