Darvon and Darvocet Overdose “Black Box” Warning Required by FDA

UPDATE 11/19/2010: Darvon and Darvocet were recalled by the FDA in November 2010.

The FDA announced Tuesday that they are requiring a new “black box” warning about the risk of overdose with Darvocet and Darvon, despite recommendations from consumer advocacy groups and their own panel of independent experts that the drugs should be removed from the market.

Darvon and Darvocet are two of the most popular members of a family of painkillers that contain propoxyphene. The new regulations will require manufacturers of all propoxyphene-based drugs to place the most stringent warning label possible under federal regulations on packaging. In addition, the FDA is requiring a new safety study regarding the effects of the drugs on the heart at high doses, and will require manufacturers put more information regarding overdoses and proper use of the drugs in medication guides.

Propoxyphene is an opioid which has been used in painkillers since 1957. Recently, propoxyphene drugs have been linked to a number of fatal overdoses, both accidental and intentional, especially in Europe. There are also concerns that the drug causes heart problems at high doses. The FDA said a difference in use patterns between European users and U.S. users played a factor in the decision to allow the drugs to remain on the market with stronger warnings.

The consumer advocacy group Public Citizen originally filed a petition with the FDA in February 2006 calling for a recall of Darvon and Darvocet, which have been associated with over 2,000 accidental deaths. They subsequently filed a lawsuit against the FDA in June 2008 as a result of the agency’s failure to take any action on their petition.

An FDA advisory panel was convened in late January 2009 to review the safety of the drugs. The panel of outside advisors recommended that the FDA withdraw approval for Darvon and Darvocet, indicating that the minimal pain relief benefits provided by the drugs do not outweigh the substantial risk of overdose, suicide and other known side effects.

While the FDA usually follows the recommendations of their advisory panels, they are not required to adhere to them. In the announcement of the new labeling requirements, the FDA noted that its health-risk standards differed from those used by the advisory panel, and said that in the agency’s view, the benefits of the painkillers still outweighed the health risks.

The FDA announcement states that the agency is looking into conducting several studies that will examine a number of health databases to determine the actual risk factors of Darvon and Darvocet, as well as other propoxyphene-based drugs. The studies could include looking at medical examiner data, Veterans Administration databases or working with the Centers for Medicare and Medicaid Services.

The FDA says it may take further action in the future if study results warrant it.