In a separate analysis, the FDA office that handles painkillers said Darvon is a weak pain reliever. Most studies show that in Darvocet, the widely used combination drug, the Darvon component appears to contribute "little or no" additional pain relief beyond that provided by the acetaminophen component, reviewers said.

Wolfe presented the advisory panel with new data from the government's Drug Abuse Warning Network, which tracks emergency room visits and deaths. It showed that Darvon-related deaths rose to 503 in 2007, from 446 in 2006. In both years, about 20 percent were suicides. The network covers only about one-third of the U.S. population.