The combination of herbal medicine Weng-li-tong with Tolterodine may be better than Tolterodine alone in the treatment of overactive bladder in women: a randomized placebo-controlled prospective trial

BACKGROUND: To assess the efficacy and safety of the herbal medicine, Weng-li-tong (WLT) as monotherapy or combined with tolterodine in women with overactive bladder (OAB). METHODS: A prospective, randomized, single-blind multi-center trial was performed which included 182 OAB patients treated with either placebo (n = 26), WLT (n = 52), tolterodine (n = 52) or WLT plus tolterodine (n = 52). The overactive bladder symptom score (OABSS) and micturition behavior were measured to evaluate treatment efficacy. RESULTS: In total, 146 patients [placebo (n = 23), WLT (n = 39), tolterodine (n = 41) and WLT plus tolterodine (n = 43)] completed 8 weeks of treatment. Compared to those treated with placebo, patients in three intervention groups showed significant improvements in the OABSS, voiding frequency, average voided volume and urgency incontinence. WLT had a slower onset than tolterodine or combination therapy in reducing urgency incontinence. Compared with tolterodine, WLT had a weaker effect in improving OABSS (P = 0.022) and daily voiding frequency (P = 0.034). The combination therapy had better efficacy than WLT or tolterodine alone in improving the OABSS, voiding frequency and voided volume. No significant differences in the changes in quality of life scores were observed among the three intervention groups. Residual urine increased significantly in tolterodine group (P = 0.004), but not in combination group. WLT resulted in fewer adverse effects than tolterodine such as dry mouth (P = 0.002), weak stream (P = 0.002) and less residual urine (P < 0.001). CONCLUSIONS: WLT could improve OAB symptoms in women, while it had slower onset and weaker efficacy but fewer adverse effects than tolterodine. The combination of WLT and tolterodine was more efficacious than tolterodine alone in improving OAB symptoms. TRIAL REGISTRATION: Chinese Clinical Trial Registry [ ChiCTR-IPR-14005626 ]. Date of registration: 7 December 2014.