A new study adds to the pile of growing evidence to support the link between Viagra and skin cancer.

Along with his colleagues, Dr. Reober Fiel of the University of Tubingen conducted different experiments on animal and human cell cultures. More specifically, the scientists observed how the cell cultures reacted to Sildenafil, the main ingredient of Viagra.

Researchers found that Sildenafil had effected the messenger molecule cyclic quanosine monophosphate (cGMP), which encourage the growth of skin cancer tumors.

The observed growths were determined to be malignant melanoma tumors, and they had used the cGMP to open the pathway for their development. Dr. Feil explains that cells normally contain the enzyme, phosphodiesterase type 5 (PDE5) that breaks down the cGMP. Sildenafil inhibits this function, which allows for the development of melanoma.

Earlier studies have found similar results, linking Sildenafil to skin cancer with melanoma being particularly high risk. However, due to other variables outside the studies, such as the participants’ lifestyle choices like sunbathing or sun exposure, the researchers could not definitively prove the link.

Two other studies had linked the condition to Sildenafil but was not able to determine if the skin cancer was due to the biological mechanism of the drug.

Dr. Feil concluded that he could not definitely state that Viagra or other Sildenafil products could cause melanoma, but recommended that doctors monitor the doses prescribed to patients.

However, the researchers believe that the risk is increased if the drug is taken frequently and in high doses.

Overview of the Viagra Melanoma Association

Skin cancer is the most common type of cancer Americans face, with melanoma being the most fatal. Medical experts explain that melanoma normally develops from melanocytes, which produces the pigment cells that gives the patient’s skin color.

However melanocytes are also responsible for the formation of moles, in which melanoma often develops from. Luckily this is a very treatable cancer, with 99 percent of the cases cured if caught early. However, if left untreated then the melanoma can spread to the liver, lungs, brain, and bones.

Once the disease spreads, treatment options are limited and the survival rate lowers considerably.

Viagra was released in 1998, and has since earned Pfizer Inc. billions from men suffering from erectile dysfunction. However, was discovered that melanoma may be included in Viagra side effects, with a 2014 study suggesting that Viagra may double the risk of melanoma.

A number of former Viagra patients have chosen to file legal action against Pfizer and generic manufacturers, for failing to warn them against Viagra skin cancer. Potential claimants should contact a specialized lawyer, to determine whether or not they have a lawsuit.