Viagra is one of the most-prescribed drugs in pharmaceutical history. Since its introduction in 1998, Pfizer has earned billions and billions of dollars from its “little blue pill,” the first prescription medication to treat erectile dysfunction. In fact, Pfizer has responded to demand by selling Viagra directly to men, with a prescription through an online website. A recent study found that men currently using Viagra to treat erectile dysfunction were 84 percent more likely to develop melanoma when compared to men not using the drug. In light of this information, attorneys are investigating whether Pfizer In. knew, or should have known, about a link between Viagra and melanoma to help determine whether patients can take legal action. In April 2014, the Journal of the American Medical Association published a study that found men using Viagra are at a significantly increased risk of developing melanoma. In the study, researchers reviewed data from more than 25,000 participants in the Health Professionals’ follow-up Study. The researchers found that when compared to men not using the drug, men with a history of Viagra use were twice as likely to develop melanoma, while men currently taking the drug were at an 84 percent increased risk.