Comparison of Two Different Drugs for Overactive Bladder, Solifenacin and Mirabegron: A Prospective Randomized Crossover Study

To assess the efficacy and safety of 2 drugs for overactive bladder (OAB), solifenacin and mirabegron. Fortyseven female OAB patients were randomized into 2 groups. Twenty-three patients were initially prescribed solifenacin for 4 weeks, followed by mirabegron for 4 weeks (group S). The other 24 patients were initially prescribed mirabegron for 4 weeks, followed by solifenacin for 4 weeks (group M). Evaluations included clinical determination of the OAB symptom score (OABSS), International Prostate Symptom Score (IPSS), and Visual Analog Scale. The IPSS significantly improved after the administration of solifenacin in both groups. The OABSS significantly improved in both groups after 4 weeks. In group M, the OABSS after eight weeks was significantly improved compared to that after 4 weeks. However, in group S, it was not significantly improved. Twelve patients experienced adverse events during the solifenacin treatment, while 2 patients experienced adverse events during the mirabegron treatment. Both solifenacin and mirabegron led to improved OAB symptoms. Switching from mirabegron to solifenacin significantly improved the OABSS. However, mirabegron led to fewer adverse events than solifenacin. We recommend that mirabegron be prescribed first for OAB patients. If patients are not satisfied with mirabegron, solifenacin should be used.