Viagra Report Spurs Reaction

Possible Link To Blindness Prompts Call For Serious Warnings

(CBS)  Those would be men over 50 with diabetes, high blood pressure, heart disease. Coincidentally, that is the same population of men most likely to be taking Viagra, notes Kaledin. So until the FDA can prove or disprove a causal link, that population should really check with their doctor about this.

Viagra and its competitors are blockbuster drugs that revolutionized treatment of erectile dysfunction, and they already come with serious warnings: They're not to be used by men who take nitrate-containing drugs, because the interaction could cause deadly drops in blood pressure, or by men with heart conditions whose doctors have warned that sex itself could be too much exertion

Viagra and its competitors work by slightly dilating arteries so that blood flow in the penis increases. Whether it affects blood flow to the eye isn't known, but Pomeranz argued that some effect on the optic nerve is plausible.

So he urged that ophthalmologists ask patients whether they use impotence drugs, and report any additional cases. Also, Viagra users who suffer blindness in one eye should be cautioned that continued use might raise the risk of vision loss in the other eye, Pomeranz wrote.

Big money is at stake. Pfizer Inc. said in its most recent quarterly filing with the Securities and Exchange Commission that sales of Viagra rose 5 percent — to $438 million — in the first quarter of the year.

Pfizer shares declined Friday on the New York Stock Exchange after news of the blindness cases.