Medical Management of Ureteral Stones Tamsulosin (Flomax ) has been shown to help increase the passage of ureteral calculi. According to a metaanalysis compared to patients receiving conservative therapy only, patients receiving conservative therapy plus α -blockers were 44% more likely to spontaneously expel the stones (RR 1.44, 95% CI 1.31 to 1.59, p0.001), and stone expulsion incidence increased significantly (RD 0.28, 95% CI 0.22 to 0.34, p0.001). Mechanism of action: Alpha blockage results in ureteral smooth muscle relaxtion and subsequent inhibition of ureteral spasms and dilatation of the ureteral lumen. Erturhan S. Erbagci A. Yagci F. Celik M. Solakhan M. Sarica K. Comparative evaluation of efficacy of use of tamsulosin and/or tolterodine for medical treatment of distal ureteral stones. [Comparative Study. Journal Article. Randomized Controlled Trial] Urology. 69(4):633-6, 2007 Apr. Parsons JK. Hergan LA. Sakamoto K. Lakin C. Efficacy of alpha-blockers for the treatment of ureteral stones. [Journal Article. Meta-Analysis] Journal of Urology. 177(3):983-7; discussion 987, 2007 Mar.