Men’s bedroom woes are often treated with the blue pill that improves the sex lives of millions across the world.  Although erectile dysfunction treatment has successfully helped both men and their partners turn up the heat in between the sheets, the impotence drug could be deadly for men. According to a recent study published in the journal JAMA Internal Medicine, Viagra users are twice as likely to develop deadly skin cancer — melanoma.

Dr. Abrar Qureshi, professor and chair of the dermatology department in the Warren Alpert Medical School at Brown University, and his colleagues suggest men should not stop taking Viagra to treat erectile dysfunction but believe those at risk for skin cancer should speak with their doctor. “[P]eople who are on the medication and who have a high risk for developing melanoma may consider touching base with their primary care providers,” Abrar told NBC News. The researchers believe the impotence drug may affect the same genetic mechanism that allows skin cancer to become more invasive.

To investigate the association between the use of sildenafil — known as Viagra — and the risk of incident melanoma among men in the U.S., the team of researchers at several sites in the U.S. and China, analyzed data from a 2000 Health Professionals’ Follow-up Study on nearly 26,000 men. The 2000 Health Professionals’ Follow-up study collects data about male health care workers, including doctors. The average age of the participants in the study was 65, and six percent had taken Viagra.

Every two years, the study gathered data such as the incidence of skin cancers, including melanoma, squamous cell carcinoma (SCC), and basal cell carcinoma (BCC), from self-reported questionnaires. The diagnosis of melanoma and SCC was medically confirmed during the 10-year follow-up. The participants who reported cancers at the start of the study were excluded.

The findings revealed the group that had a history of Viagra use had roughly double the risk of developing melanoma than those who hadn’t ever taken the drug, while those who were currently taking the impotence drug faced a 84 percent higher risk. Even after the researchers adjusted for a family history of skin cancer, ultraviolet light exposure in the states where the men lived, other kinds of cancer and major illnesses, and other factors, the findings still held true. The researchers did not find an increase in the more common and less dangerous skin cancers — SCC and BCC — among Viagra users, the Daily Mail reported.

The researchers believe it’s still too early to alter prescriptions of the blue pill because the findings warrant further investigation into its link to melanoma. Dr. June Robinson of Northwestern University’s Feinberg School of Medicine, who wrote an accompanying editorial on the study, suggests doctors who treat older men taking Viagra should check their patients for signs of skin cancer. She raised a “cautionary note” on the impact of Viagra on melanoma, saying the rate of increase in new melanoma cases in men actually slowed after Viagra entered the market in 1998. “But its role in the biological behavior of melanoma in older men warrants further study,” Robinson said.

The recent study questions the findings of a 2011 study, conducted by Dr. Viktor Umansky and his colleagues at the University Medical Centre Mannheim. Viagra was shown to cancel the suppression of a specific melanoma tumor’s inflammatory immune response in a group of mice. However, the findings of this study do raise some issues since the trial was conducted on mice and may not be as accurate when applied to humans.

While the scientific data on Viagra and skin cancer risk still warrants further investigation, researchers suggest users and doctors remain alert. Well-known Viagra side effects include heartburn, nausea, and headaches. The impotence drug is not suitable for men with angina, or very high blood pressure. More than 9,000 people die of melanoma in the U.S. each year, according to the Centers for Disease Control and Prevention, and more than 6,000 of these patients are men.

 

Sources:

Han J, Li WQ, Qureshi AA, Robinson KC. Sildenafil Use and Increased Risk of Incident Melanoma in US Men: A Prospective Cohort Study. JAMA Intern Med. 2014.

Baniyash M, Bazhin AV, Borrello I, et al. Chronic inflammation promotes myeloid-derived suppressor cell activation blocking antitumor immunity in transgenic mouse melanoma model. PNAS. 2011.