Effects of tadalafil on erectile dysfunction in men with diabetes.

OBJECTIVE To evaluate the efficacy and safety of tadalafil taken as needed before sexual activity by men with diabetes and erectile dysfunction (ED). RESEARCH DESIGN AND METHODS Men with type 1 or type 2 diabetes and a minimum 3-month history of ED were randomly allocated to one of three groups: placebo (n = 71), tadalafil 10 mg (n = 73), or tadalafil 20 mg (n = 72) taken up to once daily for 12 weeks. Changes from baseline in mean scores on the erectile function domain of the International Index of Erectile Function (IIEF) and changes from baseline in the proportion of "yes" responses to question 2, "Were you able to penetrate?," and 3, "Were you able to complete intercourse?," of the Sexual Encounter Profile were coprimary outcome measures. RESULTS A total of 191 (88%) of 216 patients completed the study. Treatment with tadalafil significantly improved all primary efficacy variables, regardless of baseline HbA(1c) level. Therapy with tadalafil also significantly improved a number of secondary outcome measures, including changes in other IIEF domains, individual IIEF questions, and percentage of positive responses to a global assessment question measuring erection improvement. Treatment with tadalafil did not alter mean HbA(1c) levels. Tadalafil was well tolerated, with headache and dyspepsia being the most frequent adverse events with active treatment. CONCLUSIONS Tadalafil therapy significantly enhanced erectile function and was well tolerated by men with diabetes and ED.