(AP) -- For the first time, abuse of painkillers and other medication is sending as many people to the emergency room as the use of illegal drugs.
In 2008, ERS saw an estimated 1 million visits from people abusing prescription or over-the-counter medicines - mostly painkillers and sedatives. That was about the same number of visits from those overdosing on heroin, cocaine and other illegal drugs, according to a government report released Thursday.
Only five years earlier, illegal drug visits outnumbered those from legal medications by a 2-to-1 margin.
In other words, the number of ER visits from medication abuse doubled, said Peter Delany of the Substance Abuse and Mental Health Services Administration.
"It's a pretty startling jump. It's a problem," Delany said. He led a team that worked with the Centers for Disease Control and Prevention on the report.
Painkillers and sedatives clearly drove the trend. ER visits for the painkillers oxycodone and hydrocodone more than doubled from 2004 to 2008. And cases from one kind of tranquilizer nearly doubled.
The estimates are based on emergency room data from more than 200 U.S. hospitals. Many of the cases may be overdoses, but some may come from mixing drugs or combining them with alcohol, Delany said.
Health officials are not sure why painkiller abuse rose so dramatically. But the number of prescriptions has been increasing, so some of those who ended up in ERs may have gotten their medicine legally.
The authors did not estimate how many of the ER patients died. A CDC report last year found that the rate of drug-related deaths roughly doubled from the late 1990s to 2006, and most of the increase was attributed to prescription opiates such as the painkillers methadone, Oxycontin and Vicodin.
"The abuse of prescription drugs is our nation's fastest-growing drug problem," Gil Kerlikowske, director of the Office of National Drug Control Policy, said in a statement.
The report is being published this week in a CDC publication, Morbidity and Mortality Weekly Report.
Explore further: How Wagner's operas held secrets of his disabling migraines and headaches
More information: The report: http://www.cdc.gov/mmwr