The two most widely prescribed arthritis pain medications, Vioxx and Celebrex, have recently been linked to an increased risk of heart attacks. News about the unexpected link to cardiovascular problems has taken many people by surprise. Researchers note that the risk of heart attack caused by Vioxx or Celebrex is small, probably only an increase of 0.3 to 0.5 percent. However, a leading cardiologist points out that millions of people take these drugs and even this small increase can result in large numbers of heart attacks.

Both Vioxx and Celebrex are part of a class of relatively new pain relievers known as cox-2 inhibitors. These new drugs relieve pain with less stomach upset and ulcers than do aspirin and other traditional pain relievers.

Scientists at Merck Research Laboratories followed 8,000 rheumatoid arthritis patients randomly assigned either Vioxx or naproxen, a traditional pain reliever. The study found that patients taking Vioxx had nearly 25% more heart attacks than those taking naproxen. The study's author said there were two explanations for this result, either naproxen has a protective effect or Vioxx, manufactured by Merck, increases the risk of heart attacks. The Food and Drug Administration recently demanded that Merck explain to physicians that either naproxen protects against heart attacks of Vioxx increases cardiovascular risk.

Meanwhile, the manufacturer of the cox-2 inhibitor Celebrex, Pharmacia Corporation, is trying to distance itself from the Vioxx study. A Pharmacia representative claims that Celebrex is not linked with any increase in heart attacks or strokes. Pharmacia is now facing a barrage of questions from physicians about the cardiovascular effects of its drug.