(CNN)-- If you are not grappling with cancer-related pain, you probably should not be taking prescription methadone.
That is the message spiraling out of startling statistics suggesting using methadone inappropriately is linked to one-third of prescription painkiller overdose deaths.
Methadone accounted for a mere 2% of prescriptions in 2009, according to Centers for Disease Control and Prevention data that spans 10 years and 13 states, but was responsible for 30% of prescription painkiller deaths.
"Methadone is riskier than other opiates for treating non-cancer pain," said Dr. Thomas Frieden, director of the CDC, who added that there is limited scientific evidence it works for chronic non-cancer pain. "It should only be used for pain when other drugs haven't been effective."
Frieden distinguished between methadone that is used to treat addiction to heroin, for example, and the increased use of prescription methadone as a first-resort for treating chronic pain.
It appears that some methadone deaths may be traced back to the 4 million prescriptions written for the drug each year in the United States. But according to the CDC report, "Studies using medical examiner data suggested... that most persons who overdosed were using it without a prescription."
And while there has not been a dramatic increase in the number of prescriptions written for methadone over the years, the overdose rate from 1999 to 2009 increased about six-fold.
CDC data do not characterize how methadone overdose deaths occur, but it is known that prescription opiates can depress the functioning of the central nervous system. Taking too much methadone - or mixing it with other CNS-depressants like oxycodone, hydrocodone or even alcohol - could effectively stop breathing.
"(Methadone) acts differently in different people's bodies," said Frieden. "They take a small amount but it could last days in their bodies and cause serious problems."
What can be confusing for patients taking the drug is that methadone is long-acting - it tends to linger in the body. That means that after the pain-relief wears off, the drug could still be circulating in someone's system. Patients get into trouble when similar-acting drugs are also introduced during this time.
But methadone can also be deadly alone. According to this week's CDC Morbidity and Mortality Weekly Report, methadone accounted for about 40% of single-drug opioid deaths.
The risk of overdose is higher when methadone is first prescribed, if the dose is increased, or if your doctor recently switched you to methadone from another medication, according to consumer information about the drug posted on the National Institutes of Health website.
Methadone may owe its status as a preferred painkiller to the fact that it's cheaper than other prescription opiates, according to Frieden. But cheap does not equal effective.
"Using methadone for pain is pennywise and pound foolish," said Frieden.
"The societal costs of saving a dollar or two from a pill," in terms of deaths, addiction and other problems, he added, "are just too great."
Some solutions to the prescription opiate problem may lie in actions already being undertaken by some states, including prescription drug monitoring programs.
And the onus is also on doctors, according to the CDC's most recent Vital Signs report.
"Providers should use methadone as an analgesic only for conditions where benefit outweighs risk to patients and society," according to the report. "Methadone and other extended-release opioids should not be used for mild pain, acute pain, 'breakthrough' pain, or on an as-needed basis."