The makers of Darvon, Darvocet and other painkillers that contain propoxyphene are being required to strengthen the drugs’ labels, including their boxed warning, to emphasize the potential for overdose. However, the Food & Drug Administration (FDA) has rejected a petition from a consumer advocacy group to remove Darvon and similar drugs from the market.
Propoxyphene has been on the market since 1957. It is a widely prescribed member of a group of drugs known as opioids and is used as a treatment for mild to moderate pain. The most frequent side effects of propoxyphene include lightheadedness, dizziness, sedation, nausea, and vomiting.
Like certain other classes of pain medications, propoxyphene products can be addictive and have been linked to deaths in patients, especially when used with alcohol and other drugs. The drug labels’ currently warn of those risks. In February, an FDA advisory panel had voted 14-to-12 to withdrawal drugs like Darvon from the market, citing its overdose risks. However, the FDA is not bound to follow the recommendations of its advisory panels.
In addition to the stronger label warnings, the FDA is requiring the manufacturers of these drugs to provide a medication guide to patients stressing the importance of using the drugs as directed.
Propoxyphene manufacturers are required to submit the requested safety labeling changes to the FDA within 30 days, or to provide a reason why they do not believe such changes are necessary. If they do not submit new language, or if the FDA disagrees with the language the companies propose, the Food, Drug, and Cosmetic Act provides strict timelines for discussions regarding the changes. At the end of these discussions, the FDA may issue an order directing the labeling changes as deemed appropriate to address the new safety information.
In addition, the FDA is requiring a new safety study assessing unanswered questions about the effects of propoxyphene on the heart at higher than recommended doses. Findings from this study, as well as other data, could lead to additional regulatory action. To further evaluate the safety of propoxyphene, the FDA plans to work with several groups including the Centers for Medicare & Medicaid Services and the Veterans Health Administration to study how often the elderly are prescribed propoxyphene instead of other pain relievers and the difference in the safety profiles of propoxyphene compared to other drugs.
However, the FDA also said today that it had rejected a petition from the advocacy group Public Citizen requesting a phased withdrawal of propoxyphene. The agency said in its response that despite serious concerns about propoxyphene, the benefits of using the medication for pain relief at recommended doses outweighs the safety risks at this time.
The Public Citizen petition was filed in 2006. In 2008, the group filed a federal lawsuit seeking to force the FDA to act on the petition.