After years of debate over their safety, FDA has moved to withdraw painkillers Darvon and Darvocet, plus the multitude of generic copycats. Why now? The agency says it received new data showing that propoxyphene, an active ingredient in both drugs, increases the risk of serious--even fatal--abnormal heart rhythms.
"These new heart data significantly alter propoxyphene's risk-benefit profile," the FDA's John Jenkins says in a statement. "The drug's effectiveness in reducing pain is no longer enough to outweigh the drug's serious potential heart risks."
Some would argue that the risk-benefit profile has been stacked too heavily on the risk side for years. Potentially addictive, the drug is also difficult to dose, because there's a fine line between an effective dose and a toxic one, the New York Times notes. The consumer watchdog Public Citizen started agitating for Darvon's demise back in 1978. Then, in 2005, the U.K. yanked propoxyphene drugs on worries about overdosing. Public Citizen followed up with another petition for withdrawal in 2006.
Last year, European regulators advised withdrawal; soon after, an FDA advisory panel recommended that the agency pull the drugs off the market, but the agency decided to put a boxed warning on them instead. At the time, FDA asked Darvon's maker, Xanodyne, to conduct a new study--and that's the study that unveiled the heart-rhythm troubles. The agency now is asking physicians to stop prescribing the drugs and recommends patients contact their doctors about alternatives.