Three-year update of sildenafil citrate (Viagra) efficacy and safety.

In the three years since its launch, sildenafil citrate (Viagra), an oral agent for the treatment of erectile dysfunction (ED), has been prescribed to more than 10 million patients worldwide and has been further evaluated in clinical studies in diverse patient populations. Significant improvements in erectile function have been demonstrated in double-blind, placebo-controlled trials in patients with ED and underlying diabetes, cardiovascular disease, minor depression, spinal cord injury and multiple sclerosis. Promising results have also been reported for patients with treated prostate cancer, end-stage renal failure, Parkinson's disease, and spina bifida and in multiple organ transplant recipients. Accounts of sildenafil use in clinical practice and postmarketing data reflect clinical trial findings of effectiveness in a broad spectrum of ED aetiologies and overall good tolerability. As in the clinical trials, most adverse events associated with sildenafil use have been transient, mild or moderate effects that rarely lead to treatment discontinuation.