Viagra Linked to Prostate Cancer Recurrence Risk: Study

The findings of a new study suggest that men who have already beat prostate cancer may face an increased risk of recurrence if they use Viagra or other similar erectile dysfunction drugs.

Research published last month in The Journal of Urology challenges a previously held belief that a class of drugs known as phosphodiesterase type 5 (PDE5A) inhibitors, which includes Viagra, Cialis and other similar drugs, may actually help suppress tumor growth. German researchers found an increased risk of prostate cancer returning in men who used the prescription medications for erectile dysfunction and impotence.

The study looked at data on 4,752 men with prostate cancer who were treated with prostatectomy between January 2000 and December 2010. They then compared the risk of biochemical recurrence of prostate cancer between those who were prescribed Viagra or other PDE5A inhibitors and those who were not.

Researchers conducted a median follow up of 60.3 months on the patients involved in the study, looking for prostate cancer recurrence within five years. They found that the use of drugs that work like Viagra increased the risk of prostate cancer recurrence by 38%.

“Contrary to experimental data, the use of phosphodiesterase type 5 inhibitors after radical prostatectomy may adversely impact biochemical recurrence,” the researchers concluded. “Further studies are needed to validate our results.”

Viagra Cancer Concerns

The study comes amid increasing concerns that side effects of Viagra may cause certain men to face an increased risk of developing melanoma; a deadly form of skin cancer. The concerns stem from Viagra’s suppression of natural cancer-fighting agents in the body which some say allows melanoma to more easily take root and spread.

In April 2014, researchers from Harvard Medical School published the findings of a new study in the medical journal JAMA Internal Medicine, which found that men who took Viagra were 84% more likely to be diagnosed with melanoma than men who do not use the drug.

Researchers hypothesize that Viagra lowers levels of a cancer-fighting protein called PDE5A. This, in turn, results in melanoma skin cancer cells becoming more invasive.

According to the American Cancer Society, melanoma is diagnosed in about 69,000 Americans each year and causes about 8,650 deaths annually. The skin cancer usually manifests as unusual moles or patches of skin.

While it is often curable if caught early, once melanoma has spread beyond the skin and local lymph nodes, treatment is difficult and it may ultimately result in death. This has raised serious questions about why Pfizer failed to warn about the potential link between Viagra and skin cancer, which may have allowed men to avoid the development of life-threatening melanoma by more carefully monitoring for skin changes.

The latest study may raise questions whether Viagra’s affect on PDE5A opens men up to increased risk of multiple types of cancer.

A number of men are now reviewing potential Viagra cancer lawsuits against Pfizer, alleging that the drug maker knew or should have known about the potential risks, yet withheld information and warnings from consumers and the medical community.