AIM: To examine the effect of prophylactic tamsulosin in male candidates of cataract surgery on general anesthesia in preventing urinary retention.

METHODS: In this double blind clinical trial, 67 male candidates of cataract surgery under general anesthesia randomly received oral tamsulosin(0.4mg daily for one week prior to cataract surgery, n=32), or placebo(n=35). Rates of post-operative urinary retention and floppy iris syndrome were compared between the two groups.

RESULTS: The two groups were matched for the patients' age(tamsulosin group: 68.16±8.72 years, placebo group: 71.37±8.60 years, P=0.38). Post-operative urinary retention occurred less frequently in tamsulosin receivers(3.1% vs 48.6%, P<0.001, Odds ratio=29.28, 95% CI 3.59-238.79). There was only one case(2.9%)with floppy iris syndrome in the control group(P=0.52, Odds ratio=1.03 95% CI 0.97-1.09).

CONCLUSION: Short-term prophylactic administration of oral tamsulosin before cataract surgery on general anesthesia is effective in preventing post-operative urinary retention without increasing the risk of floppy iris syndrome.