Viagra: a class action future?

The FDA is looking into blindness as possible side effect of Viagra, the AP reported today.

WASHINGTON -— Federal health officials are examining rare reports of blindness among some men using the impotence drugs Viagra and Cialis, a disclosure that comes at a time when the drug industry can ill afford negative publicity about another class of blockbuster medicines.

The Food and Drug Administration still is investigating, but has no evidence yet that the drug is to blame, said spokeswoman Susan Cruzan.

This type of blindness is called NAION, or non-arteritic anterior ischemic optic neuropathy. It can occur in men who are diabetic or have heart disease, the same conditions that can cause impotence and thus lead to Viagra use.

The FDA has 42 reports of the blindness, 38 among users of Viagra and four among users of Cialis. There were no cases reported among users of Levitra, the third impotence drug.

“Analyst Jason Napodano of Zacks Investment Research Inc. said he doesn’t think Viagra sales will stumble because of the new reports because the number of cases is so small.”

Doctors and patients have become increasingly wary of the downsides of prescription drugs after Merck & Co. yanked its pain reliever Vioxx from the market last year because of its potentially lethal side effects.

Merck potentially faces thousands of lawsuits over Vioxx and analysts have estimated its liability may reach $18 billion.

Pfizer was asked to remove its pain reliever Bextra from the market because of its side effects and sales of its other arthritis drug Celebrex are falling. Vioxx, Celebrex and Bextra all fall into a category of drugs known as Cox-2 inhibitors.

Industry critics have been demanding that drug companies conduct more post-marketing studies in order to do a better job of discovering side effects once drugs hit the market.

For more than two decades, Americans have mostly pressed for quicker approval of what they hope can be lifesaving drugs for such diseases as AIDS and cancer. But many now are wondering if medicines — a $200 billion industry annually — are coming out too fast and doing too much harm.

Viagra also is at the center of controversy over Medicaid’s payment for prescriptions of the drug to convicted sex offenders in New York and other states.

Viagra is made by Pfizer and was approved by the FDA in 1998.