350 Urological Association (AUA) and the European Associa- tion of Urology (EAU) guideline recommend watchful wait- ing with medical treatment for patients with a stone ＜10 mm in diameter and well-controlled pain [4]. Currently, non-selective α-blockers such as alfuzosin (10 mg daily) and doxazosin (4 mg daily) and α-1a and α-1d se- lective α-blockers such as tamsulosin (0.4 mg daily) are used for the spontaneous expulsion of lower ureteral stones or to facilitate stone removal after SWL [5-7]. In Korea and Japan, only tamsulosin 0.2 mg is produced and the admin- istration of the total daily dose of tamsulosin is achieved by the use of two doses of 0.2 mg. This regimen is more oner- ous and expensive than the use of a single 0.2-mg daily dose and adverse effects such as retrograde ejaculation can be increased. Adverse effects such as dizziness, orthostatic hypotension, headache, and fatigue may occur by taking nonselective α-blockers. Presently, we compared the impact of 0.2 mg tamsulosin with that of 0.4 mg tamsulosin and 10 mg alfuzosin in pa- tients with lower ureteral stones of 4 to 10 mm in diameter and with controlled pain, with the aim of clarifying the treatment regimen that is superior for spontaneous stone expulsion. MATERIALS AND METHODS 1. Materials Patients presenting with only one single lower ureteral stone, 4 to 10 mm in size, at the emergency department or urologic clinic at our institution were evaluated for study participation in a prospective manner between September 2008 and June 2011. Patients were enrolled upon diagnosis with normal renal function that did not require hospital- ization and intervention for stone removal. The patients were excluded if they met any of following criteria: 1) uri- nary tract infection, 2) moderate or severe hydronephrosis, 3) hypotension, 4) single kidney, 5) bilateral ureteral stones, 6) history of previous surgery on the ipsilateral ure- ter, 7) currently taking an α-blocker, steroid, or calcium channel blocker, 8) renal insufficiency, 9) ＜18 years of age, and 10) pregnant or lactating woman. A total of 156 pa- tients were enrolled and 15 patients were excluded. The randomization list was generated by using the permuted block method and was concealed from the patient-enrolling investigators (confined with a doctor assisting in the proce- dure but not participating in the study). When a patient met the inclusion and exclusion criteria, the assigned treatment was disclosed. A total of 141 patients were classified into four treatment groups. All patients received an initial treatment of 90 mg diclofenac by intramuscular injection and 5 mg cime- tropium bromide by intravenous injection, with a second dose after 30 minutes or 1 hour if necessary. All patients received trospium chloride (50 mg, tablet) every 8 hours un- til their next visit. Patients in group 1 (n=41) and group 2 (n=30) received an oral dose of 0.2 mg tamsulosin once or twice daily, respectively. Patients in group 3 (n=36) re- Korean J Urol 2012;53:349-354 Cha et al ceived a daily oral dose of 10 mg alfuzosin. Patients in group 4 (n=34) received trospium chloride. 2. Methods Before the treatment, urinalysis, blood urea nitrogen, crea- tinine level, plain kidney ureter and bladder radiographs (KUB), intravenous pyelogram (IVP), or ultrasound views of the kidney, ureter, and bladder were obtained for all patients. If the stone was not identified exactly, un- enhanced computed tomography (CT) was obtained. Similar measurements for stones 5 to 10 mm and 2 to 13 mm in size have been reported between non-contrast spiral CT and plain KUB for distal ureteral stones [8,9]. Therefore, we evaluated stone location and size by using KUB images and noncontrast CT. Follow-up visits were performed on days 7, 14, 21, and 28. At each follow-up visit, the spontaneous passage of stones, the stone expulsion time, and side effects were eval- uated and every patient underwent a plain KUB, ultra- sonography, urinalysis, and determination of serum creatinine. Also, patients were asked to observe for stone passage during urination; if they had not noticed stone ex- pulsion with a stone-free ureter, the mean date between the date of the last positive image study and the most recent follow-up was recorded. The study medications were discontinued after sponta- neous stone expulsion, intervention, or at the end of the study period. No expulsion of the stone at the end of the study and intervention before the end of the study as the result of uncontrolled pain or other serious events were con- sidered failed therapy. 3. Statistical analyses Statistical analysis was performed by using SPSS ver. 13.0 (SPSS Inc., Chicago, IL, USA) software. One-way analysis of variance was used to compare continuous variables be- tween the four groups, and different continuous variables between the two groups were tested by using Student's t-test. Nominal parameters were analyzed by using Pearson's chi-square and Fischer's exact test. A p-value ＜0.05 was considered significant. RESULTS 1. Patient characteristics The mean stone size was 5.49±1.31 mm for group 1, 5.73±1.57 mm for group 2, 5.81±1.26 mm for group 3, and 5.59±1.44 mm for group 4. There were no statistically sig- nificant differences between the four groups with respect to age, sex, body mass index, stone size, stone localization, or symptom duration. The demographic data are summar- ized in Table 1. 2. Stone expulsion rate The calculi passed through the ureter spontaneously in 32 patients in group 1 (78.0%), 23 patients in group 2 (76.7%), 27 patients in group 3 (75.0%), and 16 patients in group 4