Darvon, Darvocet (Propoxyphene) Withdrawn Due To Risk of Cardiac Toxicity

Risks Associated With Darvon and Darvocet Outweigh Benefits
Patients suffering from pain often turn to medication for relief. But those patients shouldn’t have to sacrifice their health for that pain relief. Xanodyne Pharmaceuticals Inc., which makes Darvon and Darvocet, the brand version of the prescription pain medication propoxyphene, voluntarily agreed recently to withdraw the medication from the U.S. market at the request of the FDA. The FDA’s request for withdrawal of propoxyphene comes after new clinical data revealed that that the drug puts patients at risk of potentially serious or even fatal heart rhythm abnormalities. Ultimately, the FDA determined that based on the drug’s risks, the drug should no longer be available to consumers. “The drug’s effectiveness in reducing pain is no longer enough to outweigh the drug’s serious potential heart risks,” said John Jenkins, M.D., director of the Office of New Drugs in the FDA’s Center for Drug Evaluation and Research.

Events Leading Up to the Withdrawal
Propoxyphene is an opioid used to treat mild to moderate pain. It was first approved by the FDA in 1957. The drug is sold by prescription either under the name Darvon (the drug alone) or as Darvocet (when in combination with acetaminophen). The FDA had received two previous requests to remove propoxyphene from the market, but up until now, had determined that the pain relief benefits outweighed the safety risks of the drug. Now however, that opinion has changed.

In June 2009, the European Medicines Agency began a phased withdrawal of propoxyphene. A month later, the FDA decided to permit continued marketing, but required that a new boxed warning be added to the drug label, cautioning patients about the risk of a fatal overdose. At that time, the FDA also required Xanodyne to conduct a new study looking at the effects of propoxyphene on the heart. It was from that study that the FDA made its determination that, even when taken at recommended doses, propoxyphene causes significant changes to the electrical activity of the heart. Subsequently, the withdrawal request was made.

The result revealed severe health issues associated with the drugs. The health issues however, do not appear to be irreversible. “With the new study results, for the first time we now have data showing that the standard therapeutic dose of propoxyphene can be harmful to the heart,” said Gerald Dal Pan, M.D., M.H.S., director of the Office of Surveillance and Epidemiology, CDER. “However, long-time users of the drug need to know that these changes to the heart’s electrical activity are not cumulative. Once patients stop taking propoxyphene, the risk will go away.”

The FDA’s Recommendation
The FDA has recommended that healthcare professionals stop prescribing and dispensing propoxyphene products to patients. It has also asked that patients currently taking such medication be contacted and informed of the risk of the drug and alternative pain management strategies. These patients are to discontinue use of the drug. Patients were also advised to discard unused propoxyphene in the household trash by following the recommendations outlined in the Federal Drug Disposal Guidelines.

Conclusion
Discomfort from pain can negatively impact all aspects of your daily life. Finding the right pain medication can make that pain bearable and significantly improve your quality of life. But it is imperative that the pain medication you select doesn’t create additional health issues. It is too late for consumers who have Darvon or Darvocet to rethink their purchase of those pain medications. It is not too late however, to stop using those pain relievers.