Both antimuscarinics and beta-3 adrenoceptor agonists are generally used as first-line pharmacotherapy for overactive bladder (OAB). This study aimed to investigate the differences in clinical characteristics and manifestations between different medication groups using real-world data. In this retrospective study, we recruited all patients aged > 18 years diagnosed with OAB at our institute from March 2010 to December 2017. They were allocated into three groups, the antimuscarinics (group A), beta-3 adrenoceptor agonist (group B), and discontinued (group C) treatment groups, and they completed OAB symptom score and quality of life questionnaires before and after treatment. In addition, the Clinical Global Impression was recorded for treatment outcomes. A premedication urodynamic study was also applied. A total of 215 patients were analyzed (group A: 43, B: 35, C: 137). Group B was significantly older (mean age 77.4 years) than group A (69.2 years, p = 0.012) and group C (68.6 years, p = 0.001). However, there were no significant differences in sex or underlying diseases among the groups. Before treatment, there were no significant differences in the questionnaire results among all groups. The cystometric capacity of group A (mean ± SD, 257.3 ± 135.1 cm3) was significantly larger than that of group B (125.8 ± 46.0 cm3, p = 0.002) and group C (170.5 ± 99.2 cm3, p = 0.001). After treatment, there were no significant differences between group A and group B in any of the questionnaire scores; however, their scores were better than those of group C. The OAB patients who adhered to antimuscarinics tended to be younger and have larger cystometric bladder capacity in the urodynamic study. However, there were no significant differences in effectiveness between the patients who took antimuscarinics and those who took a beta-3 adrenoceptor agonist.