Drug overdose deaths rose for the 11th straight year, federal data show, and most of them were accidents involving addictive painkillers despite growing attention to risks from these medicines.

In 2010, the CDC reported, there were 38,329 drug overdose deaths nationwide. Medicines, mostly prescription drugs, were involved in nearly 60 percent of overdose deaths that year, overshadowing deaths from illicit narcotics. Prescription drugs were up 6 percent from 2009. Opioids, like oxycodone and Vicodin, were involved in most deaths related to prescription drug overdose, with their death toll at 16,651 in 2010, up 7 percent from 2009. Prescription drug overdose deaths quadrupled from 1999 to 2010.

"The big picture is that this is a big problem that has gotten much worse quickly," said Dr. Thomas Frieden, head of the Centers for Disease Control and Prevention (CDC), which gathered and analyzed the data.

The report appears in the Journal of the American Medical Association.

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