Viagra is a treatment for erectile dysfunction, and with approval from the U.S. Food and Drug Administration (FDA) in 1998 it became the first oral therapy for male impotence. Pfizer created Viagra and has earned billions of dollars in revenue thanks to its popularity over the last several years. Viagra under other names is also used to treat hypertension, or high blood pressure, in some patients.

Millions of men have found relief from erectile dysfunction thanks to the medication often referred to as “the little blue pill.” Unfortunately Viagra can cause some problems too, including some potential serious side effects as well as interactions with other medications. Most troubling, though, is the link between Viagra use and melanoma, the deadliest type of skin cancer. Several individuals have started lawsuits against Pfizer for melanoma and other health problems linked to use of Viagra.

What is Viagra?

Viagra is a brand name drug from Pfizer, which was developed to treat erectile dysfunction in men. The generic name for the drug is sildenafil. Another brand name for sildenafil is Revatio. This is marketed for the treatment of pulmonary arterial hypertension (PAH). PAH is high blood pressure in the blood vessels that carry blood into the lungs. Sildenafil helps adults with this type of high blood pressure to be able to exercise by minimizing symptoms like shortness of breath, tiredness, and dizziness.

Although sildenafil can be used to treat PAH in adults it is most known for treating erectile dysfunction. It is this purpose that has made the drug Viagra such a success. In 2013 alone, Viagra revenues totaled over $2 billion. The FDA first approved Viagra for erectile dysfunction in 1998 and it took off immediately. It has remained steadily popular with patients and doctors ever since. Studies show that ten percent of men between ages 40 and 70 have serious erectile dysfunction, while 25 percent have moderate or occasional erectile dysfunction, so it’s no wonder Viagra has been such an important money maker for Pfizer.

How it Works

Sildenafil belongs to the drug class called phosphodiesterase inhibitors. It acts on enzymes to cause vasodilation, or the dilation and relaxation of blood vessels. When blood vessels are relaxed and dilated, it stimulates blood flow. The increased blood flow helps a man with erectile dysfunction to get and maintain an erection. For the treatment of PAH, the relaxation of the blood vessels leads to lowered blood pressure.

Side Effects

There are many possible side effects that may be caused by Viagra, but a few are the most common. These include headaches, flushing of the skin, abnormal vision, back pain, nausea dizziness, nasal congestion, indigestion, muscle pain, and a skin rash. These side effects are not usually serious and should decrease or go away entirely. If they persist or are severe, they should be reported to a doctor.

There are also some possible side effects of sildenafil that can be very serious. If you experience any of these while taking Viagra or Revatio, you should see your doctor right away: chest pains, painful urination, ringing in the ears, shortness of breath, sudden decreases or loss in either hearing or vision, lightheadedness and fainting, or an erection that lasts for more than four hours or is painful.

Vision Loss

One of the most serious and potentially damaging side effects of sildenafil is vision loss or changes in vision. Anyone taking this medication with a sudden loss of vision should stop taking it right away. Vision loss may indicate non-arteritic anterior ischemic optic neuropathy (NAION). This happens when blood flow to the optic nerve—the nerve connecting the eyeball to the brain—is restricted. It results in sudden vision loss, often noticed first thing in the morning.

Exactly why Viagra can cause NAION is not known, and the connection is still controversial. There have been several studies, though, that link Viagra use to vision loss caused by NAION. Treating the vision loss caused by NAION is not foolproof. Many people will not recover vision, but recent studies have found that treatment with corticosteroids may help.

Hypotension

Because sildenafil causes blood pressure to drop, it can also have the unwanted effect of hypotension, dangerously low blood pressure. Signs of this condition include dizziness, lightheadedness, and fainting. Patients who have hypotension while resting should not take Viagra because it can cause blood pressure to go down even lower, to dangerous levels. Taking other medications that lower blood pressure at the same time can also cause dangerous hypotension.

In addition to dizziness and fainting, when hypotension lasts over a long-term it can result in damage to the brain and heart. Blood pressure that is too low means that adequate amounts of oxygen cannot be pumped out to various parts of the body. Without enough oxygen, damage is possible. Acute, or sudden, hypotension, which is possible with Viagra use, can even cause a heart attack or stroke.

Melanoma

The most recent findings regarding adverse events with Viagra use is that the medication may be linked to an increased risk of developing melanoma. This is the most dangerous of all types of skin cancer because it tends to metastasize, or spread, to other areas of the body and other organs. Melanoma is a cancer of the skin cells that produce pigment, melanocytes.

Melanoma is highly treatable, but only if it is caught early. If it is too late, the malignant cancer cells will have spread too far. During stage I melanoma, treatment can cause remission and recovery in nearly 100 percent of cases, but by stage IV, survival rates are down to about 15 or 20 percent.

In 2014, the results of a study that involved more than 25,000 participants found that there was an increased risk of melanoma in men that had been taking sildenafil for ten years. The risk had doubled in this population as compared to a control group not using sildenafil. Results have also shown that men who have taken the medication for less than ten years still have an increased risk of melanoma.

While the study cannot prove that Viagra causes melanoma, but it does show there is a clear connection. Why this connection exists is not known, but for men taking Viagra, it is important to be aware of the risk. Men taking sildenafil should know the signs of melanoma and should be screened for it regularly so they can be treated successfully in early stages if it develops.

Lawsuits

While Viagra has proven to be a helpful drug for millions of men, some have experienced the very serious side effects it can cause and have suffered as a result. Lawsuits filed by these individuals have targeted Pfizer for not adequately warning patients and doctors of the risks taken when using the drug. There are warnings on sildenafil packages about vision loss, but warnings regarding hypotension and heart problems were not included soon enough to prevent serious issues. Men who have suffered hypotension and its complications because of Viagra have started lawsuits against Pfizer.

The risk of developing melanoma is only the latest problem associated with Viagra use, but it has the potential to become the most serious. There are currently no official warnings about this risk, which means that patients using the drug may not be aware that they need to watch for early signs of melanoma. This may lead to a lot of lawsuits against Viagra in the future, and you could be a part of these if you have developed skin cancer while taking this drug.