Tamsulosin for urolithiasis: a review of the recent literature and current controversies

In the United States, urolithiasis affects approximately 1 in 11 people, and there is evidence that the prevalence is increasing. A relatively recent treatment strategy for urolithiasis involves using medical expulsive therapy (MET) to increase the likelihood of spontaneous passage of ureteral stones. The 2 leading drug classes for MET are alpha-1-andrenergic receptor blockers and calcium channel blockers. Tamsulosin, an alpha-1-adrenocepter blocking agent, is thought to induce spontaneous stone passage by relaxing ureteral smooth muscle tone. However, tamsulosin has not been proven effective for increasing ureteral stone passage and is not approved by the Food and Drug Administration for this indication. There is a relative paucity of data on the efficacy of tamsulosin for urolithiasis, and of the published results, there are conflicting conclusions from the data. Because of the acute and often severe nature of symptoms from urolithiasis, emergency medicine physicians are frequently the first to diagnose and treat this condition. This has led to tamsulosin being frequently prescribed from the emergency department (ED) for off-label use without the support of high-quality evidence. If tamsulosin is proven effective, its use in the treatment of urolithiasis could offer several important advantages. The number of procedures, length of hospital stay, and health care costs after the initial ED visit could potentially be reduced. Tamsulosin may also increase patient satisfaction by reducing the invasive treatment and decreasing the time to stone passage. This review focuses on the efficacy of tamsulosin based on stone location, after shock wave lithotripsy, compared with other MET drugs and in the acute setting of the ED.