Women who regularly used over-the-counter pain relievers containing the drug phenacetin had higher rates of certain illnesses and death than women who used aspirin or no pain reliever, a new study has found.
While phenacetin, still used in Europe, was taken off the U.S. market in 1980 because of fears that it might cause kidney problems, experts here expressed concern.
They fear that acetaminophen, the analgesic found in drugs such as Tylenol, could have a similar effect. This is because the body converts phenacetin into acetaminophen.
But Dr. Anthony Temple, director of regulatory and medical affairs for McNeil Consumer Products of Fort Washington, Pa., the producer of Tylenol, disputed such reasoning.
"The study really doesn't have anything to suggest that there is a problem with acetaminophen even with long-term use," he said.
The researchers said they could not rule out the possibility that the unexpected illness and deaths among users of phenacetin arose from their underlying conditions.
But they noted that no excess illness or death was observed among aspirin users. The study involved people who took phenacetin regularly, regular aspirin users and people who did not use painkillers.
The results are reported in today's issue of the New England Journal of Medicine.
In an editorial accompanying the study, Dr. Paul D. Stolley of the University of Pennsylvania said that the concern is not for those who take "occasional doses for aches and pains." Instead, he said, the risks are for people who use analgesics regularly. He said the study added "to the growing body of evidence pointing to the health hazards of chronic and heavy users of analgesics."
Dr. Dale P. Sandler, an epidemiologist at the National Institute of Environmental Health Sciences in Research Triangle Park, N.C., agreed that the study had "important implications," even though it was not clear that the phenacetin findings applied to acetaminophen. "There are enough similarities there to cause concern," she said.
In the 20-year study, Dr. Ulrich C. Dubach of Kantonsspital in Basel, Switzerland, and his colleagues studied 1,244 women from the ages of 30 to 49. Half were regular users of phenacetin, and the others were not.
They found that the women who used phenacetin had a death rate more than twice as high as women who did not use this drug and that the users were 60 percent more likely to have developed high blood pressure. Aspirin use was not correlated with these effects.
High blood pressure contributed to about half of the excess deaths for heart disease and stroke, the researchers found, and it may also have contributed to the deaths from kidney and urinary-tract disease.