AbstractObjectiveTo investigate the trial of spontaneous urination without catheter (TWOC) outcomes for men with acute urinary retention, determine successful TWOC predictors, and evaluate the impact of add‐on medication therapy on TWOC.MethodsThis retrospective study included men with acute urinary retention and post‐void residual (PVR) >250 mL who underwent TWOC between July 2009 and July 2019. Patients were divided into a medicated group who received alpha1 blocker on urinary retention diagnosis and a naïve group who did not. The trial was defined as unsuccessful if the PVR was >150 mL or if the patient experienced difficulty emptying their bladder with abdominal discomfort or pain, and a transurethral catheter was reinserted.ResultsAmong 576 men with urinary retention, 269 (46.7%) constituted the medicated group and 307 (53.3%) the naïve. The naïve group comprised more elderly patients (P = 0.010) with higher Eastern Cooperative Oncology Group performance status (PS) (P = 0.001) and smaller prostate volume (P = 0.028) than the other. In the medicated group, 153 men received additional oral medication before TWOC to increase the success rate. There were significant age differences (P = 0.041) in the medicated group and significant median PS differences (P = 0.010) in the naïve group between the successful and unsuccessful outcomes of TWOC. The multivariate logistic regression model demonstrated that age <80 years in medicated patients (P = 0.042, odds ratio [OR] 1.701) and PS <2 in naïve patients (P = 0.001, OR 2.710) were significant independent predictors of successful TWOC outcomes.ConclusionsThis is the first study classifying patients with urinary retention according to medication status. Both medicated and naïve groups had different patient backgrounds and TWOC outcome predictors, suggesting a discrepant etiology behind urinary retention. Hence, acute urinary retention management in men should vary based on medication status for male lower urinary tract symptoms when urinary retention is diagnosed.