Eye Care Current Topics in Eye Care

Is There a Link Between Viagra and Blindness?

July 11, 2005—The Food and Drug Administration (FDA) has ordered the makers of Viagra, Cialis and Levitra to add new warnings about rare cases of sudden vision loss. A recent study also noted these vision problems, known as non-arteritic anterior ischemic optic neuropathy (NAION), in seven men who had taken Viagra.

The agency is advising patients to stop taking these medicines or call a doctor or right away if they experience sudden or decreased vision loss in one or both eyes. In a statement, the agency said that a small number of men lost their sight some time after taking Viagra, Cialis or Levitra. "It is not possible to determine whether these oral medicines for erectile dysfunction were the cause of the loss of eyesight or whether the problem is related to other factors such as high blood pressure or diabetes or to a combination of these problems," the FDA said.

Well over 20 million men have taken these anti-impotence drugs, meaning that whatever risk there is of developing vision loss—if there is a risk at all—would seem extremely small. Still, just how serious of a condition is NAION, and what can be done in men who develop it?

What is NAION?
NAION is one of the most common causes of sudden vision loss in older Americans.

The condition leads to swelling around the optic disc, a connection point where the optic nerves reach the back of the eye. Ultimately, this swelling compresses the optic nerves and causes a rapid drop in vision. About 6,000 people develop NAION each year, according to the National Eye Institute.

How does NAION develop?
The symptoms are painless and often appear without notice. In a study led by researchers at the University of Iowa, about three quarters of NAION patients first discovered their vision was blurry and impaired after waking up in the morning. The condition starts in one eye and can cause complete blindness if both eyes are eventually affected.

Is there a risk from Viagra and other anti-impotence drugs?
No one can say for sure. Pfizer, the manufacturer of Viagra, defends the safety of its drug. "A review of 103 Viagra clinical trials involving 13,000 patients found no reports of non-arteritic anterior ischemic optic neuropathy," the company stated. "There is no evidence showing that NAION occurred more frequently in men taking Viagra than men of similar age and health who did not take Viagra."

Andrew Schachat, MD, an ophthalmologist with the Wilmer Eye Institute at Johns Hopkins University, who has no financial ties to Pfizer, is equally skeptical. "With the millions of patients who use Viagra, it is not surprising to find cases of NAION and in fact, one would expect to find some," he said.

The FDA continues to investigate whether there is a connection. Schachat said he doubts Viagra or other anti-impotence drugs cause NAION, "but a careful study would be needed."

Page 1 of 2 Next Page >>