The melanoma question about these drugs is genuinely unsettled
Men on these drugs are diagnosed with melanoma somewhat more often. One pooling of 866,049 reads that as sunlight showing through; a later one calls it reason to avoid them.
What the study found
Two meta-analyses read the same melanoma data opposite ways
Men on these drugs are diagnosed with melanoma somewhat more often than men who are not. One pooling of 866,049 reads that as sunlight showing through: the link shows only at low exposure, and the drugs track basal cell cancer too. A later one calls it reason for at-risk men to avoid them.
The caveat · More doctor visits, more diagnoses
Every study on both sides is observational, so men who take these drugs differ from men who do not in ways no adjustment removes, sun exposure among them. They also see doctors more often, which alone yields more diagnoses of a cancer found by looking. The newer pooling's studies barely agree.
What we don't know
Men on erectile-dysfunction drugs are diagnosed with melanoma more often. What that means is unsettled: one analysis reads it as shared sun exposure, and a later one urges at-risk men to avoid the drugs without answering that argument.