Popular erectile dysfunction drug Cialis could cause serious side effects, such as an increase in melanoma, the deadliest form of skin cancer.

Cialis is a PDE5 inhibitor, just like Viagra, which has also been linked to an increased risk of melanoma skin cancer. One of the body’s cancer-fighting proteins is PDE5.

Interestingly, there does not appear to be a correlation between an increase in basal cell or squamous cell carcinomas as Cialis side effects, only the most feared – melanoma.

Study of Viagra and Melanoma

In April 2014, the JAMA Internal Medicine medical journal wrote of a study from Harvard Medical School that saw an 84% increase in melanoma among men who took Viagra over those who did not.

Because it was an observational study of 25,000 men, it did not show a definitive cause and effect relationship between Viagra use and melanoma, but it did show a correlation.

Even after adjusting for other risk factors, the men who had recently used Viagra were twice as likely to develop melanoma.

Because Cialis was not available at the time the men were studied, it was not part of this study. However, because Cialis also inhibits cancer-fighting PDE5 and is longer acting, its probability of also fostering melanoma growth is most apt.

Cialis and Melanoma Possibly Linked

In 2011, the medical journal Cancer Cell alerted Viagra and Cialis users that PDE5 inhibitors could encourage melanoma cell invasion. The Journal of Cell Biochemistry in 2012 published a study that determined PDE5 inhibitors such as Viagra and Cialis could promote melanoma development.

Viagra maker Pfizer is already facing several lawsuits regarding their erectile dysfunction drug and allegedly increased incidences of deadly melanoma.

At the very least, PDE5 makers should have warned physicians and men about the possible increased risk of melanoma by those who ingested their product.

Cialis is a product from Eli Lilly and Co. and French pharmaceutical company Sanofi. The companies made a push a couple of years ago to try to get Cialis to be sold over the counter without a prescription. The FDA did not approve.

What Is Melanoma?

Melanoma is a cancer that starts in the melanocytes, which are the cells that skin its tan or brown color. Melanin protects the deeper layers of our skin from some of the harmful effects of the sun. Most of the time, skin exposed to the sun encourage the melanocytes to make more of the pigment, resulting in a tan.

Melanoma can develop anywhere on the skin, but men are more likely to see it on their chest or back, whereas women are more apt to have spots on their legs. The neck and face are also common melanoma sites for both sexes.

Signs of melanoma are usually brown or black spots, but some melanomas can make the skin appear pink, tan or white. Any change in a mole or pigmentation of the skin should be checked by a doctor because if caught early, melanoma can be much less likely to spread. Melanoma is deadly when it metastasizes to other organs.

What Can You Do?

While there are studies still underway regarding the PDE5 inhibitors such as Cialis and Viagra and their link to melanoma, the correlation is already very strong, as is the chemical explanation.

If you or a loved one has taken Cialis and subsequently developed melanoma allegedly from Cialis side effects, you could be eligible for financial relief through a class action lawsuit.