Pfizer faces a Viagra melanoma warning lawsuit claiming that prolonged use of Viagra can cause melanoma.

Plaintiff John H. accuses Pfizer Inc. of not disclosing melanoma as a possible side effect of long-term Viagra use. The plaintiff wants the manufacturer to update products with a Viagra melanoma warning.

John says he began taking Viagra in February 2007 and consistently took the drug through July 2016. In March 2011, John claims, he was diagnosed with melanoma, a cancer of the skin.

According to the National Cancer Institute, melanoma is the most serious variety of skin cancer and more likely than other cancers to spread to other parts of the body. This makes the cancer more dangerous in terms of overall tissue damage and more complicated to treat than other cancers which are less likely to spread. John’s Viagra lawsuit argues his prolonged use of Viagra caused him to develop melanoma.

Viagra (sildenafil citrate) was first approved by the FDA in 1998 as a treatment for men with erectile dysfunction. Erectile dysfunction is a condition in which a man can’t achieve or maintain an erection sufficient for satisfactory sexual activity. Viagra was developed by Pfizer to inhibit certain enzymes thought to be responsible for erectile dysfunction. Pfizer also sells sildenafil citrate under the brand name “Revatio” to treat pulmonary arterial hypertension, a type of high blood pressure that affects the pulmonary artery.

The Viagra lawsuit alleges that many different studies have shown the link between Viagra and melanoma, but Pfizer has not included the risk in their drug warnings. John argues that, with the amount of scientific evidence available linking Viagra and melanoma, Pfizer should be required to include a Viagra melanoma warning with their product.

“Despite these significant findings, Pfizer has made no efforts in its ubiquitous Viagra advertisements to warn users about the increased risk of developing and/or the exacerbation of melanoma that has been scientifically linked to its drug,” the lawsuit states.

Viagra holds around 45 percent of the U.S. market for erectile dysfunction medications. Pfizer estimates that over 35 million men worldwide have been prescribed Viagra. John argues that Pfizer does not include a melanoma risk in their warnings because they do not want to jeopardize their worldwide profit.

“[Pfizer] was willfully blind to, ignored, downplayed, avoided, and/or otherwise understated the serious nature of the risks associated with the use of Viagra in order to increase sales,” the lawsuit alleges.

John argues that Pfizer should include a Viagra melanoma warning with their product and that to not do so is a violation of proper business practices. “Pfizer purposefully downplayed, understated and outright ignored the melanoma-related health hazards and risks associated with using Viagra,” the lawsuit accuses.

John accuses Pfizer of negligence, unfair and deceptive trade practices, strict liability, failure to test, breach of warranty, misrepresentation, concealment, fraud and deceit, willful, wanton, and malicious conduct, and unjust enrichment. He seeks a trial by jury, damages, medical expenses, attorney’s fees, and court costs.

The Viagra Melanoma Warning Lawsuit is Case No. 3:18-cv-01342 and is part of the Viagra Melanoma MDL, In re: Viagra (Sildenafil Citrate) Products Liability Litigation, Case No. 16-md-02691-RS, in the U.S. District Court for the Northern District of California.