Long-term safety and effectiveness of sildenafil citrate in men with erectile dysfunction.

Because sildenafil citrate is a treatment, not a cure, for erectile dysfunction (ED), many men may choose to use it for an extended period. Men with ED who had previously completed 1 of 4 double-blind trials with short-term open-label extension (combined duration, 0.9-1.2 years) were eligible for this 4-year, open-label, extension study, which assessed the safety and effectiveness of flexible doses (25, 50, and 100 mg sildenafil) used as needed. Adverse events that were serious or led to dosing changes or discontinuation (temporary or permanent) were recorded. Many of the 979 participants (mean age, 58 [range, 27-82] years; mean ED duration, 4.5 years) had concomitant hypertension (28%), diabetes (22%), or hyperlipidemia (14%). Overall, 37 (3.8%) had treatment-related adverse events (none serious) requiring dosage change or discontinuation and 62 (6.3%) discontinued because of insufficient response. At each yearly assessment, more than 94% of participants responded affirmatively to the questions: "Are you satisfied with the effect of treatment on your erections?" and "If yes, has treatment improved your ability to engage in sexual activity?" These results argue against the loss of tolerability or the development of tachyphylaxis over a prolonged period of as needed, flexible-dose sildenafil treatment of men with ED.

The pharmacokinetics and hemodynamics of sildenafil citrate in male hemodialysis patients.

BACKGROUND: Erectile dysfunction (ED) is highly prevalent in men with renal disease. The clearance of sildenafil citrate, a highly effective oral treatment for ED, is decreased in men with severe renal insufficiency, but the pharmacokinetic and hemodynamic profiles during maintenance hemodialysis in men with end-stage renal disease have not been studied. METHODS: Fifteen men undergoing chronic outpatient maintenance hemodialysis received a single 50-mg oral dose of sildenafil on 2 occasions, once 2 hours before, and once 2 hours after hemodialysis, with randomized assignment to sequence. Blood and dialysate samples were collected, and hemodynamic measurements were made. RESULTS: Hemodialysis did not significantly clear either sildenafil or its primary metabolite, UK-103,320. Administration after hemodialysis was associated with a 17% higher peak plasma concentration and earlier time to peak, which were not clinically meaningful, whereas the overall extent of absorption and the elimination half-life were not affected. The average extent of drug bound to plasma protein was approximately 96% in hemodialysis patients. Intradialytic hypotension was not observed more frequently when sildenafil was administered before hemodialysis. Systolic blood pressure tended to decrease less during hemodialysis when subjects were treated with sildenafil before dialysis. CONCLUSION: The present study demonstrates that sildenafil is not cleared by hemodialysis, and the pharmacokinetic profile resembles more closely that observed in normal volunteers than that observed in patients with severe renal insufficiency. In addition, we found that sildenafil does not promote intradialytic hypotension.

Efficacy and safety of sildenafil citrate in men with erectile dysfunction and stable coronary artery disease.

This was a double-blind, placebo-controlled, flexible-dose study of the efficacy and safety of sildenafil in men with erectile dysfunction (ED) and clinically stable coronary artery disease (CAD). Patients were randomized to receive sildenafil or placebo for 12 weeks. Primary outcomes were questions 3 and 4 of the International Index of Erectile Function (IIEF). Secondary outcomes included the other IIEF questions and functional domains, the Life Satisfaction Checklist, the Erectile Dysfunction Inventory of Treatment Satisfaction, 2 global efficacy assessment questions, and intercourse success rate. By week 12, sildenafil-treated patients (n = 70) showed significant improvements on questions 3 and 4 compared with placebo-treated patients (n = 72; p <0.01). Larger percentages of sildenafil-treated patients reported improved erections (64%) and improved intercourse (65%) compared with placebo-treated patients (21% and 19%, respectively). Sildenafil-treated patients were highly satisfied with treatment and their sexual life compared with placebo-treated patients. Forty-seven percent of sildenafil- and 32% of placebo-treated patients experienced adverse events, including transient headache, hypertension, flushing, and dyspepsia. There were no serious drug-related cardiovascular effects. Thus, sildenafil is an effective and well-tolerated treatment for ED in men with CAD. Sildenafil was not associated with additional safety risks in this patient population.