The prescription painkiller OxyContin may not be the sole culprit behind the hundreds of drug overdoses for which it's been blamed.
Researchers have found that most of the drug-abuse deaths associated with oxycodone -- a morphine-like painkiller that is the active ingredient in OxyContin, Percocet and other medications -- are the result of mixing several drugs.
The overdoses have prompted increased regulatory scrutiny of prescriptions nationwide, making some doctors reluctant to prescribe the drug, even for patients in severe pain.
"We found that the oxycodone deaths were primarily related to mixing many different kinds of drugs with these opiates," says Edward J. Cone, lead author of the study and a forensic toxicologist. "These drugs often have a synergistic effect on each other, and in combination can be a deadly brew."
Researchers solicited the records of 1,243 oxycodone-related cases from medical examiners in 23 states from August 1999 through January 2002. OxyContin caused only 12 of these deaths, and another 18 were linked to oxycodone. In the vast majority of cases (96.7%), victims had at least three other drugs in their system, such as benzodiazepines (Valium-like drugs), alcohol, cocaine, marijuana, antidepressants or other narcotics.
This finding is in stark contrast to the figures compiled last year by the U.S. Drug Enforcement Administration, which lists OxyContin as the cause of 146 deaths, and the "likely" cause of an additional 318 fatalities.
Purdue Pharma, the Stamford, Conn., maker of OxyContin, funded the study, which was in the March issue of the Journal of Analytical Toxicology.