Mirabegron as a Medical Expulsive Therapy for 5-10 mm Distal Ureteral Stones: A Prospective, Randomized, Comparative Study

Objective: The aim of this study was to assess the efficacy and safety of mirabegron as a medical expulsive therapy in patients with distal ureteral stones of 5-10 mm size. Material and methods: A prospective, comparative study included 96 patients with radiopaque distal ureteral stones of 5-10 mm who were randomly allocated and treated by medical expulsive therapy in 2 groups from January 2019 to December 2020. Patients in group A received only ketorolac 30 mg/day for 5 days, then on demand. Patients in group B received mirabegron 50 mg/day for 4 weeks plus ketorolac 30 mg/day like in group A. The stone expulsion rate was the primary outcome. Results: There were no significant differences regarding age, gender, body mass index, laterality, degree of hydronephrosis, and stone size. After 4 weeks, stone expulsion rate was 52.1% for group A versus 89.6% for group B (P < .001). The median (range) of time to stone expulsion was 14 (13-23) and 7 (3-16) days for groups A and B, respectively (P = .004). The medians (range; interquartile range) of episodes of renal pain (1 (0-2; 1) vs. (0-2; 2); P < .001) and extra analgesic ampoules (1 (0-7; 4) vs. 0 (0-2; 0) vials; P < .001) were significantly higher in group A than those in group B, respectively. In multivariate analysis, only medical expulsive therapy (P < .001) and stone size (P < .001) were independent predictors of stone expulsion rate. Conclusion: Mirabegron is an effective and safe medical expulsive therapy agent in patients with 5-10 mm distal ureteral stones.