By Pete Williams, NBC News
According to the 2015 National Drug Threat Assessment Summary, deaths from drug overdoses climbed to 46,471 in 2013, the most recent year for which figures are available.
"Roughly half of the overdose deaths are related to abuse of prescription drugs and another 8,000 involve heroin. So combined those two things account for two-thirds of the overdose deaths," said DEA Administrator Chuck Rosenberg. Click here to read the NBC News story.