Erectile dysfunction is common in dialysis patients. We report our experience with sildenafil citrate in patients undergoing dialysis therapy. Male subjects attending the Outpatient Dialysis Unit at the University of Pennsylvania (Philadelphia, PA) who were prescribed sildenafil by their primary physician or nephrologist were asked to complete the International Index of Erectile Function before their first dose of sildenafil and after at least 4 weeks of therapy. Subjects' mean age was 50.3 +/- 14.63 (SD) years. Ninety-three percent of the subjects were black. Based on a global efficacy question, 66.7% of the subjects believed that treatment had improved their erections. Subjects reported no increase in the sexual desire domain despite experiencing a significant increase in erectile function, orgasmic function, and satisfaction with intercourse. Sildenafil was well tolerated in a selected group of patients who reported improved sexual function with no major adverse effects.