Well, it was too good to last, wasn't it? Pfizer's star drug and worldwide bestseller, Viagra, is under the microscope after several reports of blindness subsequent to its use are coming in.
The company is currently in talks with the Food and Drug Administration regarding issues related to updating the label on the drug. In a statement Pfizer said, "Pfizer is in discussions with the Food and Drug Administration to update the Viagra label to reflect these rare ocular occurrences. Viagra has a strong safety profile and remains an effective medication that benefits millions of people." Viagra supposedly causes non-arteritic anterior ischemic optic neuropathy after prolonged use. In people over 50 years of age the drug causes irreparable vision loss.
The FDA is investigating almost 50 reports of blindness, "We take this seriously," FDA spokeswoman, Susan Cruzan said. She added that as of now there was no direct evidence to blame Viagra. Pfizer spokesman Daniel Watts confirmed that the company was in discussion with the FDA. Pfizer's website lists Viagra as an exceptionally safe drug, "The most common side effects of Viagra are headache, facial flushing, and upset stomach. Less common are bluish or blurred vision, or being sensitive to light. These may occur for a short time," a statement on the site says.
Viagra was approved in 1998 by the FDA as a treatment for erectile dysfunction and has since been used by almost 20 million people worldwide. Viagra should not be used in men whose doctors have already warned them to cut back on sex. It is also considered unsafe in people who are on nitrates since it causes a sudden drop in blood pressure. The current problem, non-arteritic anterior ischemic optic neuropathy (NAION) is also known to occur in men with heart disease or diabetes.
Dr Howard Pomeranz, co-author of a report on the condition published in the Journal of Neuro-ophthalmology in April maintains that the drug has a long history of ocular problems. He added that a simple screening test would overcome the problem. So far the problem was not heard of since men never thought it necessary to inform their ophthalmologist that they were on Viagra, he said in an interview to a news channel. Pfizer counters, "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," Pfizer is already in the FDA's book since the agency asked it to remove its pain reliever Bextra from the market. Pfizer's arthritis drug Celebrex is also not faring that well in the market. Viagra has been a goldmine for the company with sales of the drug netting the company $438m (£240m) in the first quarter of the year.
But Viagra has been in the news recently after a report asked states to stop payments for the drug in convicted sex offenders. In the backdrop of this news Pfizer stock fell by 2 percent in morning trading.
