Testosterone therapy for low sexual interest and erectile dysfunction in men: a controlled study.

A double blind cross-over comparison of testosterone and placebo injection was carried out in two groups of men with normal circulating testosterone levels, 10 complaining principally of loss of sexual interest and 10 complaining principally of erectile failure. A significant increase in sexual interest was produced by testosterone in the first group. There was no effect on erectile function in either group. These results support previous findings from hypogonadal men that testosterone influences sexual interest but not erectile function, and indicate that increasing plasma testosterone can effect sexual interest even in men with pre-treatment testosterone levels within the normal range.