Tamsulosin for Distal Ureteral Stones
Tamsulosin hydrochloride vs Placebo for Management of Distal Ureteral Stones
Archives of Internal Medicine, Vol. 170, December 13, 2010
The pendulum regarding treating small kidney stones with alpha-blocking agents continues to swing back and forth. The literature prior to this study is imperfect, being influenced by industry-sponsorship and suffering from methodological flaws. There have been several meta-analyses and SRs which draw (consequently biased) conclusions from that data too.
This article attempts (and succeeds to a certain point) to put the controversy to bed.
This was a multicenter (6 French hospitals), placebo-controlled, randomized, double-blinded study of 129 patients who were admitted (not typical in the US-experience) for distal ureteric stones between 2- and 7mm. The primary endpoint was time to stone expulsion. Several secondary endpoints included, amongst others, safety, side effects, need for surgery and drew contrast between stones 2-3mm and those 4-7mm.
The strengths, and therefore reliability of their results, lie in the methodological rigor exercised during this study. It finds no difference between placebo and daily 0.4mg tamsulosin dosing in time to stone expulsion (primary endpoint), with both groups passing the stone in approximately 3-days. There were no differences in secondary endpoints either.
The obvious drawback to the study is the small sample size, only 129 patients. The study was powered only to detect a big difference in outcome (ie. an 8-day difference)
This study finds that giving Tamsulosin makes no difference in time taken to pass a small distal stone.
There is a chance that bigger studies or a meta-analysis of a number of high quality studies (like this one) would be able to detect a smaller difference, and may yet see a usefulness to Tamsulosin in distal kidney stone passage.