What Is Viagra?
Viagra (Sildenafil) is the first drug ever developed to treat erectile dysfunction in men. Produced in the early 1990’s Viagra was originally developed by Pfizer to treat heart disease. While trials showed that the drug had little effect in treating heart disease, men taking Viagra reported an increase in erections after taking the drug. Pfizer quickly conducted additional trials and repurposed the drug as a treatment for impotence in men. Approved for use by the FDA in 1998 to treat erectile dysfunction, Viagra exploded in popularity and became one of the most well known drugs in the world. For Pfizer, Viagra was a home run with an estimated 35 million prescriptions to date and revenues of 1.3 billion dollars worldwide in 2013 alone.
Viagra Dangers
Despite being hailed as a miracle solution to erectile dysfunction, Viagra use is not without its cautions. As early as 1999, some Viagra users were reporting changes in vision even lost eyesight. In 2007, the FDA required Viagra to include warnings on its label for risks of vision impairment / loss, hearing loss, heart attacks, and stroke when taking the drug.
Viagra and Melanoma Risk
Viagra’s problems have not ended there as another serious side effect has surfaced. Recently a study done by the peer reviewed Journal of American Medicine Association (JAMA), reported that there may be a link between men taking Viagra and an almost 2 fold increased risk in developing Melanoma, a deadly skin cancer.
What Causes Erectile Dysfunction
Erectile dysfunction, also known as male impotence, affects around 30 million men worldwide. According to the National Institute of Health, erectile dysfunction is the persistent inability to achieve or maintain an erection that is satisfactory for sexual intercourse. It occurs when the arteries in the penis do not relax enough when the brain sends the chemical signal to allow sufficient blood flow into the penis. Without enough blood flow to the penis, a man cannot achieve or maintain an erection.
How Does Viagra Works To Treat Erectile Dysfunction?
Viagra (Sildenafil) belongs to a class of drugs called PDE-5 (phosphodiesterase type 5) inhibitors. Viagra and other PDE-5 inhibitors work to treat men with erectile dysfunction by slowing the degradation of the chemical, cGMP (cyclic guanosine monophosphate), that allows increased blood flow to the penis. By reducing the rate of cGMP degradation, Viagra helps men produce and maintain an erection. As cGMP is only active when an individual is sexually stimulated, Viagra should only be effective in producing an erection under those circumstances.
Viagra Side Effects
Viagra received several label changes from the FDA due to its serious side effects after reports of users having sudden vision or hearing loss. Other Viagra side effects generally include:
![]() Headache |
![]() Indigestion |
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![]() Dizziness |
![]() Painful / frequent urination |
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![]() Numbness or tingling |
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Blurry vision or peripheral vision loss |
Study Links Viagra Use to Melanoma Skin Cancer
In 2014, Li et al published a study in JAMA Internal Medicine which demonstrated a significantly higher risk of melanoma for men using Viagra. The study looked at over 25,000 participants in the Health Professionals Follow-Up Study (HPFS) which began in 1986. The study published by Li et al involved a survey regarding the presence of erectile dysfunction and measures taken to address it. Data was also gathered regarding factors relevant to the development of skin cancer, such as the presence of moles, natural hair color, sun exposure, family history of melanoma and others.
Participants of the HPFS report cancer diagnoses every 2 years, including diagnoses of melanoma, squamous cell carcinoma and basal cell carcinoma (all related skin cancer). Using the data they gathered regarding Viagra use and skin cancer risk, Li et al identified that for Viagra users, the risk of melanoma was more than twice that of the other study participants. This study and other recent findings suggest that Viagra use may play an important role in the development of melanoma in some individuals.
Lawsuits Against Viagra
While Viagra has been hailed as a miracle drug by many men who suffer from erectile dysfunction, there are serious side effects associated with taking the drug. Men who have suffered from these side effects and would not have taken the drug had they known about the serious risks associated with the drug have filed lawsuits against the manufacturer.

Vision Loss
Some users of Viagra developed Non-Arteritic Ischemic Optic Neuropathy (NAION), an eye problem that can result in permanent blindness. Reports found that Viagra affects the blood circulation to the optic nerve, resulting in vision impairment or loss. New labeling has been approved by the FDA, requiring Pfizer to warn users about the risks of vision loss.

Hearing Loss
Users of Viagra also brought lawsuits against the manufacturer for sudden hearing loss. Some men taking viagra experienced Sensorineural hearing loss (SSHL), after taking viagra. SSHL occurs when there is damage to the inner ear structures that results to permanent ear damage. The FDA now requires Viagra’s label to warn users of the risks of hearing loss.

Melanoma Skin Cancer
New Viagra lawsuits are now being filed after a study by JAMA Internal Medicine has linked Viagra use to an increased risk of melanoma cancer in men. Researchers suggest this link is because Viagra use may allow melanoma skin cancer to be more invasive in the body. There is currently no warning label to inform users of the increased risk of melanoma skin cancer.
Other Lawsuits Against Pfizer
Pfizer’s has a long history of defending themselves in court for unethical practices. Pfizer has continuously come under legal action for a number of issues including product safety, price fixing, bribery, misleading advertising, environmental violations, and more. Below is a list of just a few of the many cases in which Pfizer’s unethical business practices have negatively affected consumers:
- Defective Heart Valves
In 1994, Pfizer settled for $10.75 million as a result of selling defective heart valves and lying to regulators to get approval for the valves.
- Defrauding Medicaid
In 2002, Pfizer paid a $49 million settlement due to charges of defrauding Medicaid by overcharging for Lipitor.
- Improper Marketing
In 2004, Pfizer set a record for healthcare fraud settlement when they paid $2.3 billion on improper marketing of 4 different medications.
- Bribing Healthcare Professionals
Pfizer came to a $45 million settlement in 2012 on charges that they had bribed overseas healthcare professionals to promote their products.
- Testing Drugs Without Consent
Following a 1996 meningitis epidemic in Nigeria, Pfizer was sued by thirty Nigerian families for testing drugs on their children without parental consent. In 2009 the company settled a portion of these cases for $75 million.