According to a new study published in JAMA Internal Medicine, researchers have identified a link between sildenafil (more commonly known as Viagra) and melanoma, or skin cancer. Not only is there an association between the two, but the authors of the study say the drug may increase a man’s risk for melanoma by up to 84 percent.

Sildenafil is used to treat erectile dysfunction, or impotence — an inability to maintain an erection — and boosts blood flow. The authors of the study reviewed 26,000 men who were enrolled in the Health Professionals Follow-Up Study at Harvard School of Public Health, which has been tracking men since 2000 about their sexual health, Viagra use, and sun exposure. They had also been tracking the men’s incidences of melanoma.

The researchers found that the men who were using Viagra had almost twice the risk of developing melanoma, but not for other types of skin cancers. However, they were unable to identify whether it was the drug itself or even erectile dysfunction that caused melanoma; there was only a correlation. Though Viagra has been linked to other minor side effects, like dizziness, headaches, and even heart problems, this is the first time it has been associated with a boost in skin cancer risk. “Although this study is insufficient to alter clinical recommendations,” the authors wrote in their conclusion, “we support a need for continued investigation of this association.”

Ironically, a previous study published a few years ago actually found opposite results: that Viagra could potentially prevent melanoma. Dr. Viktor Umansky of the University Medical Center Mannheim, Germany, found that Viagra appeared to neutralize tumors’ inflammatory immune responses in mice. However, linking mice results to humans is quite a leap, and further research would be needed before making such conclusions — on both ends. Regardless, “people who are on the medication and who have a high risk for developing melanoma may consider touching base with their primary care providers,” Dr. Abrar Qureshi, professor and chair of the dermatology department at Brown University, and a co-author of the newest study, said.