Plaintiffs have begun filing Viagra melanoma lawsuits following a study suggesting a link between the popular erectile dysfunction drug and the deadly form of skin cancer.

The study was published in JAMA Internal Medicine in April 2014. Researchers found that Viagra, or sildenafil citrate, lowers levels of an enzyme called PDE5A, increasing the invasiveness of melanoma cells.

Since the new study was published, some plaintiffs who developed melanoma after taking Viagra have begun to file Viagra melanoma lawsuits. At least three such lawsuits were filed in March, one of them in Alabama and two in Mississippi.

These lawsuits typically argue that Pfizer knew, or should have known, about the risk of developing melanoma and should have adequately warned patients and doctors about that risk. Viagra skin cancer lawsuits may result in compensation for the plaintiffs’ medical bills, lost time at work, and pain and suffering.

Victims’ loved ones can sometimes also be compensated for the harm to their relationship with the victim. If the plaintiffs can prove that Pfizer willfully withheld important information, they may also be able to collect punitive damages and attorney’s fees.

The study

From 2000 to 2010, researchers followed a cohort of almost 26,000 men who were enrolled in Harvard University’s Health Professionals Follow-Up Study. The researchers documented other factors potentially related to skin cancer such as genetic predispositions and history of sun exposure.

The results showed a significant association of Viagra use with an increased risk of melanoma. The findings suggested that use of Viagra could increase a man’s risk of developing melanoma by as much as 84 percent.

The study also examined other types of cancer such as squamous cell carcinoma and basal cell carcinoma but did not find any significant relationship between those cancers and Viagra use. The researchers clarified that the study was not sufficient to alter clinical recommendations but that it does call for further investigation.

The new study is consistent with earlier studies published in Cancer Cell in 2011 and in the Journal of Cell Biochemistry in 2012, both of which suggested a link between Viagra and melanoma.

Viagra background

Viagra was approved by the FDA in 1998 as a treatment for erectile dysfunction. It works by increasing blood flow to the genitals.

It has some known common side effects that are much less menacing than melanoma, such as warmth or redness of the face or chest, headache, upset stomach, and diarrhea. Users are recommended to stop using Viagra if they experience symptoms such as changes in vision or hearing, chest pain, irregular heartbeat, swelling in extremities, shortness of breath, or feeling lightheaded.

Melanoma is one of the more aggressive and dangerous forms of skin cancer. It accounts for fewer than 5 percent of cases of skin cancer in the United States, yet it accounts for the most skin cancer deaths.

Melanoma has a very high five-year cure rate in cases where it is caught early. But failing early diagnosis, its capacity for rapid spread can cause death within months.

Pfizer has issued a statement denying that it has identified melanoma as a safety concern related to Viagra use.