Medical Expulsive Therapy of Single Distal Ureteral Stones. A Randomised, Double-blind and Placebo-controlled Study

Current therapeutic options for ureteral stones include active intervention as well as conservative "watch and wait" approaches. Endoscopic treatment of ureteral stones has a high success rate and reliably results in immediate stone removal However, surgical as well as anaesthetic risks are not negligible and serious complications are possible. For many patients, a conservative treatment is an appealing option. Watchful waiting, however, not always results in stone clearance and may be associated with recurrent renal colics.

The therapeutic potential of alpha-blockers for ureteral stone disease has been investigated prompted by the detection of alpha-receptors in ureteral smooth muscle cells. Blocking of such receptors, which are predominantly located in the distal part of the ureter results in relaxation of the ureteral wall and modulation of peristaltic activity. This mechanism has been proposed to facilitate stone passage for ureteral calculi.

Numerous clinical trials have revealed a significant improvement of the stone expulsion rate using the alpha-blocker tamsulosin. Most of these studies were randomised but none were performed in a double-blind and placebo-controlled fashion. Therefore, the objective of this trial was to evaluate the efficacy of medical expulsive therapy with tamsulosin in a randomised, double-blind, placebo-controlled setting.