Clinical Question

Does testosterone supplementation improve the response to sildenafil (Viagra) in men with erectile dysfunction and low testosterone levels?

Bottom Line

Boosting low testosterone levels into the normal range did not further improve the effectiveness of sildenafil in men with erectile dysfunction. The researchers did not determine whether testosterone replacement alone is as effective as sildenafil for the treatment of erectile dysfunction. (Level of Evidence = 1b)

Synopsis

These researchers identified, through advertisements and through referrals from specialty clinics, 140 men with erectile dysfunction and low serum testosterone levels (i.e., total testosterone level less than 330 ng per dL [11.45 nmol per L] or free testosterone level less than 50 pg per mL [173.35 pmol per L]). The men, 40 to 70 years of age, were tested to find the optimal dose of sildenafil before being randomized, using concealed allocation, to receive testosterone 1% gel or placebo gel, in addition to continuing sildenafil. Testosterone levels were tested two weeks after the start of treatment, and the dose was titrated up or down to achieve normal levels. Sildenafil, used alone, improved erectile function in men in both groups. Intention-to-treat and on-protocol analyses found that the addition of testosterone did not significantly improve erectile function compared with the placebo. Testosterone did not affect the frequency of sexual encounters, percentage of successful sexual intercourse, sexual desire, quality-of-life scores, or marital intimacy scores.

Reference

SpitzerMBasariaSTravisonTGet alEffect of testosterone replacement on response to sildenafil citrate in men with erectile dysfunction: a parallel, randomized trial. Ann Intern Med.2012; 157( 10): 681– 691.

Study design: Randomized controlled trial (double-blinded)

Funding source: Government

Allocation: Concealed

Setting: Outpatient (any)