More than 35 million men around the world have been prescribed Viagra (sildenafil citrate),1 Pfizer’s blockbuster drug used to treat erectile dysfunction (ED). With sales of more than $2 billion in 2012,2 it seemed this drug, with its promises of instant virility and sexual prowess, was unstoppable.
Viagra holds 49 percent of the market for sexual dysfunction treatments, which, at an average cost of $22 a pill,3 is a major income stream for Pfizer – but there are signs of trouble.
For starters, sales of ED drugs have seen slow growth (just 1 percent annually) and even declines in sales of up to 7 percent in recent years. It’s also been widely observed that up to half of men who receive a first prescription for Viagra do not get it refilled.4
One theory for why not? Many men may realize that Viagra is not the miracle pill they thought it would be. It may trigger an erection, allowing for intercourse, but it will not fix relationships or build emotional connections…
The other prevailing theory? Men may get fed up with the side effects, which are high in numbers and often severe… and more potential complications are being uncovered by the day.
Viagra Use May Double Your Risk of Melanoma
Men who have ever used Viagra have nearly twice the risk of melanoma, the deadliest form of skin cancer, than men who have never used the drug, according to new research published in JAMA Internal Medicine.5 Those who had used the drug recently had an 84 percent greater melanoma risk.
While the study can’t prove that Viagra causes melanoma, it did rule out a potential erectile dysfunction connection – no link was found between ED and melanoma risk. Furthermore, the researchers explained a potential reason mechanism by which Viagra might increase cancer risk.
In short, activation of the BRAF gene has been shown to downregulate the enzyme phosphodiesterase PDE5A. Low PDE5A expression is known to increase the invasiveness of melanoma cells. Another molecule NRAS has also been shown to downregulate PDE58 in melanoma cells. What does this have to do with Viagra?
Viagra belongs to a class of drugs known as PDE5A inhibitors (along with Levitra and Cialis). Viagra works by inhibiting phosphodiesterase and increasing nitric oxide production, which may help maintain erections, but this may also explain how it could increase cancer risk. The authors noted:6
“This indicates that PDE5A suppression by sildenafil [Viagra] use mimics an effect of BRAF/NRAS activation and thus may potentially function as one of the ‘hits’ for melanomagenesis… Two PDE5 inhibitors have been shown to promote melanin synthesis, which may stimulate melanoma development…”
What Are You Really Risking When You Take Viagra?
The potential melanoma connection is only the latest in a long list of serious Viagra side effects, which include:7
- An erection that will not go away (priapism). If not treated right away, priapism can permanently damage your penis.
- Sudden vision loss in one or both eyes, which can be a sign of a serious eye problem called non-arteritic anterior ischemic optic neuropathy (NAION).
- Sudden hearing decrease or hearing loss, ringing in your ears (tinnitus), or dizziness.
If you take other medications, be aware that Viagra interacts with many and may cause even more side effects. This includes medications such as nitrates, alpha-blockers, HIV protease inhibitors, certain antibiotics and oral anti-fungal medicines, high blood pressure drugs, and more. Other commonly reported side effects include:
Headache Flushing Upset stomach Abnormal vision, such as changes in color vision (having a blue color tinge) and blurred vision Stuffy or runny nose Back pain Muscle pain Nausea Dizziness
