• Posted February 7, 2023

Kisspeptin: Is Injected Hormone the Remedy for Flagging Libido?

If you are one of the millions of people distressed by low libido, help may be on the way in the form of a new hormone shot.

Two new British studies suggest that injections of the hormone kisspeptin could boost sexual desire in men and women. When folks with low sexual desire received kisspeptin shots, areas of their brains charged with feeling sexual desire lit up on scans when they watched erotic videos.

"It's very nice to see something that works in women and men,"said co-senior study author Dr. Alexander Comninos, a consultant in endocrinology and diabetes and an honorary clinical senior lecturer at Imperial College Healthcare NHS Trust in London.

Kisspeptin may stimulate the release of other reproductive hormones, leading to enhanced desire. "Kisspeptin relieves the brake on true sexual arousal," Comninos said.

More studies in larger groups of people are needed to confirm the findings, and kisspeptin is still considered an investigational treatment.

"We are in the early stages, but in five to 10 years, we may be able to use kisspeptin to treat distressing low sexual desire in men and women,"Comninos said. However, not everyone with low libido finds it distressing or concerning.

In one study of 32 women aged 19 to 48 with low sexual desire, kisspeptin injections boosted brain activity in key brain parts responsible for arousal while watching erotic videos. These areas did not light up after placebo or dummy injections.

Women who were more distressed by their low libido showed even greater improvements in brain activity after kisspeptin shots, the study showed. What's more, these women felt sexier after kisspeptin injections.

In the second study, 32 men with distressing low sexual desire showed enhanced brain activity in key parts of the brain responsible for arousal after taking kisspeptin compared with placebo. They also showed increased penis rigidity while viewing an erotic video after kisspeptin shots.

As with women, the more distressed men were about their libidos, the greater their response to kisspeptin. Men were also happier about sex after they received kisspeptin, the study showed.

"Giving kisspeptin boosts response in these areas,"said co-senior study author Dr. Waljit Dhillo, a professor in endocrinology and metabolism and a consultant endocrinologist at Imperial College London.

Both studies, which were funded by the U.K.'s National Institute for Health Research/Imperial Clinical Research Facility and Biomedical Research Centre at Imperial College London, were published Feb. 3 in the journal JAMA Network Open.

The same researchers previously showed kisspeptin injections boosted libido in men who didn't have low sexual desire. Now, the plan is to work with pharmaceutical companies to develop and test a kisspeptin shot that can be given as needed at home, he said.

These shots could be used in people bothered by low sexual desire after other causes, such as medications, low testosterone levels or depression, are ruled out, Dhillo said.

There's not much out there to treat distressing low sexual desire. Women can take flibanserin (Addyi) or bremelanotide (Vyleesi) for low sexual desire, but both of these medications have side effects that make them undesirable for use before intercourse. Vyleesi may cause nausea and vomiting, and Addyi may lead to dangerously low blood pressure and dizziness, Dhillo said.

"Kisspeptin appears to be side-effect free,"he said.

In men, there is nothing that truly addresses low sexual desire. "This is acting in the brain,"Dhillo said of kisspeptin. "It is not a mechanical treatment like Viagra or other drugs that treat erectile dysfunction in men."

There have been very few treatments to boost libido or desire, said Dr. Carolyn DeLucia, an obstetrician-gynecologist in Hillsborough Township, N.J., and White Plains, N.Y.

"People have no idea why"¦they suddenly lose interest in sex not only with a partner, but on their own," DeLucia said. "They no longer have fantasies or find others attractive, and it often gets dismissed by providers because they feel helpless with no good treatment to offer."

Kisspeptin could change all of this if further studies pan out.

"Kisspeptin seems to be the first hormone to safely and comfortably enhance desire in both men and women,"said DeLucia, who has no ties to the new research.

Low sexual desire is the great divide, she said. "Relationships work when both parties feel loved, desired and appreciated,"DeLucia said. "When a partner no longer feels desire, doubt and frustration and a feeling of rejection set in. These feelings are corrosive, and resentment begins."

Kisspeptin may be a solution to so many failing relationships, she said.

More information

Lear more about low sexual desire at Planned Parenthood.

SOURCES: Alexander Comninos, MD, PhD, BSc (Hons), consultant, endocrinology, diabetes, honorary clinical senior lecturer, Imperial College London; Waljit Dhillo, MD, PhD, professor, endocrinology, metabolism, and consultant endocrinologist, Imperial College London; Carolyn DeLucia, MD, obstetrician-gynecologist, Hillsborough Township, N.J., White Plains, N.Y.; JAMA Network Open, Feb. 3, 2023