The Scary Side Effect of Viagra

The same pill that gives you a lift in the sack could also raise something much more serious: your risk of a deadly form of skin cancer. Taking an erectile-dysfunction (ED) drug may increase your likelihood of developing melanoma, finds a new study published in the journal JAMA Internal Medicine.

Researchers followed over 25,000 men over the course of 10 years, and found that those who reported using sildenafil—more commonly known by its brand name, Viagra—in the 3 months before the study’s start were 84 percent more likely to get melanoma during the follow-up.

Plus, the guys who reported using the drug some time before the start were 92 percent more likely to be diagnosed with the cancer compared to men who said they never used it.

More research is needed to determine what may be responsible for the increased risk, says study author Wen-Qing Li, Ph.D. But his team has one theory: The drug, which suppresses the PDE5A enzyme to help you get an erection, also mimics the activation of a mutation commonly seen in melanoma. This may spark the development of the skin cancer.

Before you toss your little blue pill, it’s important to understand that the findings don’t necessarily show a cause-and-effect relationship between Viagra use and melanoma. Plus, the actual cases of melanoma in Viagra users were very small—only 14 in 1,378 men.

Right now, Li says the results aren’t enough to alter current clinical recommendations for Viagra or other common ED drugs like Levitra and Cialis. (These weren’t included in the study since they hadn’t yet received FDA approval at its start.) Instead, more research needs to be done first on how dosage and frequency of use are related to melanoma risk.