Like women, men can lose sexual desire and feel distressed about it, meeting DSM-5 criteria for Hypoactive Sexual Desire Disorder. It’s a frequent problem, and no drug treatments address it—yet. The largest cross-sectional epidemiology study that has been conducted, the National Health and Social Life Survey of over 1200 US men age 18-59, determined that the incidence of a “problem” of lack of sexual desire was about 15%. In men under age 30, the incidence of a desire problem was double that of erection problems. Even in men over age 50, the incidence of desire problems was as high as that of ED. [Laumann 1999]

HSDD in men causes specific changes in the brain’s control mechanisms that seem to adjust sexual motivation. [Stoleru 2003] In male patients with HSDD, PET scanning (positron emission tomography) and mapping of regional blood flow in the brain have been used to measure responses to visual sexual stimuli (VSS). In control subjects one specific brain area, the medial orbitofrontal cortex, deactivated in response to VSS. In HSDD patients activity was abnormally maintained in this region. The same brain region seems to inhibit motivated behavior. By contrast, the reverse pattern–activation in control subjects, deactivation or unchanged activity in HSDD patients–was found in four other brain areas, the secondary somatosensory cortex and inferior parietal lobules, regions that mediate emotional and motor imagery processes, and in areas of the anterior cingulate gyrus and the frontal lobes that help control muscle movement.

However, HSDD is not well defined in its symptoms, in what other disorders can simulate it, or in how it can be measured. Only one study is publicly available in which men with low sexual desire were asked about their complaints, or to discriminate their problem (if not due to other causes) from other disorders that make men lose sexual desire, e.g., depression (DeRogatis 2012).

Those data show that male HSDD is a real problem of clinical magnitude. On a battery of validated rating scales, men with HSDD had highly significant impairments vs. those with no sexual dysfunction.* On the Sexual Concerns Inventory-Male, a measure of sexual distress, men with HSDD endorsed feeling dissatisfied, concerned, worried, frustrated, stressed, self-doubts, upset, unhappy, and a lack of confidence. Their scores averaged almost four times as high as for men with no Sexual Dysfunction. Sexual activity of men with HSDD was cut in half. And other scales showed that the sexual dysfunction in the men with HSDD was highly specific. They had impaired desire [Male Desire Scale impairment double that in the controls] but did not have Erectile Dysfunction [International Index of Erectile Function (IIEF)-5 median score was the same as controls]. Nor did they have depression [Beck Depression scale means were the same for both groups]. They did not even have low testosterone: men with low or low-normal testosterone levels (<300 ng/dL) were excluded. *p<0.0001 for each variable; sample sizes were about 100.