Objectives: To evaluate and compare the efficacy of tamsulosin (0.4 mg, once/day) and combinations of it with trospium (20 mg, twice/day) in the treatment of single small lower ureteral stones. Patients and methods: A total of 126 patients presenting to urology outpatient clinics from July 2012 to May 2015, with a single 5-10 mm sized lower ureteral stone were randomly classified into two treatment groups. Patients in group A (n = 62) received an oral dose of 0.4 mg tamsulosin once daily and 20 mg trospium chloride twice daily. Patients in group B (n = 64) received 0.4 mg tamsulosin once daily and placebo twice daily. The spontaneous passage of stones, the stone expulsion time, and adverse effects were evaluated. Results: There were no significant differences in baseline characteristic of the patients in both groups. Stone expulsion was observed in 47 patients (75.8%), and 58 (90.62%) in groups A and B respectively. The average time to expulsion was 11.65 +/- 5.32 days in group A and 17.35 +/- 6.21 days in group B. The spontaneous stone passage rate through the ureter was significantly higher and the stone expulsion time was faster in groups A than in group B (p < 0.05). The adverse effects observed in both groups were comparable and were mild.