The findings are based on two nationally-representative surveys that asked teenagers about their recent or lifetime use of prescription painkillers, which include drugs such as oxycontin and codeine.

Both medical and recreational use of such opioid drugs has increased across the United States over the past couple of decades, as have deaths due to painkiller overdoses.

The Centers for Disease Control and Prevention estimate that 14,800 Americans died of an opioid overdose in 2008 -- three times the number of overdose deaths 20 years earlier.

"The non-medical use of controlled medications in (teens) has surpassed almost all illicit drugs except for marijuana," said pediatrician Dr. Robert Fortuna, from the University of Rochester Medical Center in New York.

"It's just an alarming trend."

Fortuna, who wasn't involved in the new research, told Reuters Health more doctors are prescribing kids powerful painkillers for conditions like back or knee pain -- and some of those drugs may end up getting used recreationally.

But that doesn't mean any prescribing of oxycontin or related drugs is a bad idea in young people who really need them, researchers agreed.

"The majority of these kids are still using these medications as intended," said Sean Esteban McCabe, from the University of Michigan in Ann Arbor, who led one of the new studies.

McCabe and his colleagues analyzed teenagers' drug-related responses on a general survey of behaviors and attitudes that was given to about 7,400 high school seniors in 2007 through 2009.

Of those teens -- from 135 different public and private schools -- about 13 percent said they had ever used prescription painkillers for non-medical reasons, such as to get high or to relieve pain without a doctor's oversight.

Teens who said they'd used the painkillers for non-medical purposes were more likely to smoke pot or cigarettes or to binge drink, compared with those who'd only taken the pills under a doctor's supervision or not at all.

Most of the kids who used the drugs recreationally had previously been prescribed them for a medical condition. Teens may be using their own leftover medication for pain or recreational purposes, or may get painkillers from family members or friends who were prescribed the drugs, researchers said.

"There does seem to be a casual attitude held by some regarding sharing medications that have abuse potential," McCabe told Reuters Health.

"Some kids are using opioid medications to self-treat pain, and really they would benefit from a professional assessment for their pain management."

Other survey data on 12- to 21-year olds revealed that most teens who took up the habit started using painkillers at age 16 or 17 -- not at the end of high school or afterwards, as some research had suggested.

At age 16, one in 30 or 40 teens took their first non-medical painkillers, James Anthony of Michigan State University in East Lansing and his colleagues reported in the Archives of Pediatrics & Adolescent Medicine on Monday, alongside McCabe's findings.

Among both younger kids and older teens who had never used painkillers recreationally, much fewer started experimenting with them each year in comparison, based on the survey of about 120,000 youth.

The findings suggest that programs aimed at keeping kids away from painkillers should start early in high school, and not just aim at older teens or high school grads, Anthony said.

"Perhaps we've been thinking about this as an older adolescent phenomenon, or a problem that's more common among college students or high school seniors," he told Reuters Health.

But with that assumption, he added, "we're missing an opportunity for prevention of the problem of extra-medical drug use in these earlier teen years."

The 13 percent of high school seniors nationally who had used painkillers for non-medical purposes is lower than has been shown among some specific communities, such as Detroit, according to McCabe and his colleagues. So schools and communities may need to do their own analysis on whether prescription drug use is a problem for their youth before deciding how to move forward, the researchers concluded.

In the meantime, they said doctors can warn their younger patients about the abuse potential of painkillers, and parents can make sure the drugs are properly stored and disposed of to avoid misuse.

SOURCE: bit.ly/pD1ZHL Archives of Pediatrics & Adolescent Medicine, online May 7, 2012.

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