The consumer group Public Citizen is calling on the U.S. Food and Drug Administration to withdraw a popular prescription painkiller from the market.
The group says the widely prescribed pain reliever propoxyphene (Darvon, Darvocet and generic versions), should be phased out because it has been associated with more than 2,000 accidental deaths between 1981 and 1999, (nearly 6 percent of all drug-related fatalities), is physically addictive and is no more effective than safer alternatives.
In 2004, 23 million prescriptions for propoxyphene were filled, making it the 12th most commonly prescribed generic drug in the United States.
Four companies - Mylan, Mallinkrodt, Teva and QLT - account for more than 91 percent of U.S. prescriptions.
Only last year British health authorities announced a phased withdrawal of the drug because of its negligible effectiveness and the high risk of overdose and death.
They say it has been impossible to identify any patient group in whom the risk-benefit ratio may be positive.
The U.S. advocacy group is calling on the FDA to follow suit.
A large proportion of the deaths occurred because the drug is converted into a metabolite that is highly toxic to the heart and lasts longer in the body than the original compound, resulting in cardiac depression.
Adverse cardiac events associated with propoxyphene include an interruption of heart transmission of electrical impulses, slowed heartbeats and a decreased ability of the heart to contract properly.