Meta-Analysis Finds Viagra Does Not Cause Melanoma

In 2016, the FDA placed Viagra and other erectile dysfunction drugs on its safety watch list following a report that linked Viagra use with an increased risk of melanoma. However, new findings show that this is not the case.

In a study published in the Journal of the National Cancer Institute, investigators conducted a meta-analysis of published data on the association between erectile dysfunction drugs, called phosphodiesterase inhibitors (PDE5i), and melanoma risk.

More specifically, they sought to determine whether there was an association that met Hill AB’s casual criteria, including analogy, biological gradient, consistency, coherence, experiment, plausibility, specificity, strength, and temporality.

For the study, investigators analyzed data from 5 large-scale studies of PDE5i users and melanoma published between 2014 and 2016. The studies included 866,049 men, of whom 41,874 were diagnosed with melanoma.

The results of the study showed an overall 11% increase in the risk of melanoma among users of PDE5 inhibitors. However, the association was only statistically significant among men with low PDE5i exposure and with low-stage melanoma.

The investigators attribute the risk to detection bias, in which the group of patients likely to take erectile dysfunction medications are more health conscious and more likely to see a physician. Therefore, they are more likely to get diagnosed with melanoma than other men of similar age.

“Physicians should still screen for melanoma risk, but they do not need to add the use of Viagra and similar drugs to the list of screening criteria specifically,” said investigator Stacy Loeb, MD, MSc. “In general, men should continue to be careful about the risk of any kind of skin cancer from excessive sun exposure and use sun protection.”

The authors concluded that there was no evidence that erectile dysfunction medications caused melanoma.

“Overall, Viagra and other PDE5 inhibitors are safe medications as long as men are not taking nitrates, which carry a risk of reducing blood pressure,” Loeb said. “Physicians and patients should not be concerned about taking these medications on account of worry about melanoma.”