Ohio saw a record number of drug overdose deaths in 2010, as painkiller abuse and ingestion of multiple drugs at a time continued to take their toll and underscored the obstacles confronting the state as it makes unprecedented efforts to combat the problem.

The state also saw a record number of heroin deaths, which now account for one in every five overdose deaths, a trend that may be driven by painkiller addicts switching to heroin, a cheaper alternative.

The Ohio Department of Health recorded 1,544 accidental overdose deaths in 2010, the most recent year with complete data, a 5 percent increase over the next highest figure from 2008 and a 372 percent increase over the decade. Drug overdoses remained the leading cause of accidental deaths in the state, including car crashes, for the fourth straight year.

The figures reflect the rapid increase in the number of prescription painkillers that have been dispensed in the state, said Christy Beeghly, program administrator for the Health Department’s Injury Prevention Program.

“We’ve just exposed a much greater proportion of the population to these very addictive and potentially very dangerous substances,” she said Thursday. “We’re seeing the results in not just these deaths, but also in substance abuse treatment, nonfatal overdoses and other consequences.”

Ohio Attorney General Mike DeWine said state efforts in 2011 to fight prescription drug abuse included shutting down pain management clinics referred to as “pill mills” by their critics, convicting doctors and taking away medical licenses.

“Whether that, and the publicity, and the other efforts has stemmed this tide and whether numbers are starting to go down we just simply don’t know,” he said. “What we do know is in 2010 they continued to rise and that has been a steady trend since at least 1999. We are headed in the wrong direction.”

The data shows that pain medication figured in 45 percent of the overdoses in 2010, up from 39 percent in 2009. The use of multiple drugs at a time is also part of the problem, though Beeghly said it’s possible coroners are reporting the use of multiple drugs more accurately than in the past.

“Multiple drug use and mixing medications is very dangerous,” she said.

Ohio also is seeing increases in overdose deaths attributed to anti-anxiety drugs such as Valium, Ativan or Xanax, according to the Health Department.

The state recorded 338 heroin-involved deaths in 2010, or 22 percent of all drug overdoses, as addicts who can’t afford pain pills take advantage of the cheap heroin that has flooded Ohio in recent years.

Heroin use likely driven by addicts switching is now being seen in rural parts of Ohio where it’s never been recorded before, said Joe Gay, an Athens psychologist who directs substance abuse programs for a six-county region.

“The treatment system simply cannot keep up with the needs,” he said. “All across the state people are being turned away because treatment services are not available to deal with the problem.”

The state’s efforts to address the painkiller epidemic started last year with a law signed by Gov. John Kasich to crack down on pain management clinics, blamed by health officials for contributing to hundreds of overdose deaths in Ohio each year.

Last month, preliminary numbers from the Ohio State Board of Pharmacy’s automated reporting showed the number of prescribed painkiller doses and drug-related deaths decreased last year in Scioto County, the southern Ohio locale regarded as the epicenter of the state’s prescription drug addiction problem.

In December, DeWine announced that the last pain medication clinic in Scioto County had been shut down.

“We’re into this for the long battle and this is not going be easy and we’re not going to turn it around overnight,” he said Thursday.

The state saw 1,423 accidental drug overdose deaths in 2009, 1,475 in 2008 and 1,351 in 2007.