For men with erectile dysfunction and low testosterone levels, the addition of testosterone to sildenafil is not superior to sildenafil alone for improving erectile function, according to a study published in Annals of Internal Medicine (2012;157:681-691).
Matthew Spitzer, MD, of the Boston University School of Medicine, and colleagues examined whether addition of testosterone to sildenafil therapy correlates with improved erectile response in 40- to 70-year-old men with erectile dysfunction and low testosterone levels. Researchers randomly assigned 140 subjects to receive 14 weeks of daily transdermal gel containing 10-gram testosterone or placebo (70 participants each).
Administration of sildenafil alone correlated with a considerable increase in erectile function domain scores, with no significant difference between the groups. In younger men, more obese men, and men with lower baseline testosterone levels or inadequate response to sildenafil alone, similar results were seen for other domains of sexual function. Both groups had similar frequency of adverse events.
“In men with erectile dysfunction who had low testosterone levels,” the authors noted, “the addition of a replacement dose of testosterone to an optimized dose of sildenafil was not associated with greater improvement in erectile function than that associated with addition of placebo gel.”