Methadone painkiller overdoses kill about 5,000 patients a year, CDC warns

By Deborah Kotz, Globe Staff

About 5,000 patients taking the prescription painkiller methadone die every year from the drug -- the vast majority from accidental overdoses -- and they account for about 1 in 3 deaths in the United States from prescription opiates, according to a new government report.

Many of these deaths could be prevented if doctors curtailed their prescribing of this drug, said the federal Centers for Disease Control and Prevention in the report released Tuesday.

The agency said the number of deaths from methadone overdose had risen six-fold over the past decade but decreased slightly since 2007. That could indicate that more doctors are following US Food and Drug Administration recommendations to prescribe the drug for pain relief only after other opiates fail to work.

Methadone is also used to treat heroin addiction, but the CDC report focused only on the 4 million methadone prescriptions written annually for pain relief.

“Methadone is riskier than other prescription painkillers,” CDC director Dr. Thomas Frieden said during a press briefing, “and there’s really been an overuse of methadone for pain.”

Part of the reason for its popularity may be that methadone pills cost far less than other opiate painkillers such as oxycodone and hydrocodone. Some health plan drug formularies list methadone as the preferred painkiller of choice. “They’re being penny wise and pound foolish,” said Frieden. “Although [methadone] may cost a couple dollars less per pill, the result is many more emergency room visits.”

Methadone carries more risks than other painkillers because it tends to build up in the body and can cause slow or shallow breathing and dangerous changes in heart beat that, according to the FDA, may not be felt by the patient.

In Massachusetts, methadone prescriptions account for 9 to 11 percent of prescription painkillers dispensed in the state, according to the CDC report. Nationally, 9 percent of painkiller prescriptions are for methadone, the report said.

Frieden emphasized that methadone and other “extended-release” opioids -- all of which build up in the body over time -- should be mainly reserved for those with chronic pain caused by cancer and shouldn’t be prescribed for those in mild pain or acute pain due to an injury. He said they should be considered a treatment of last resort for those with chronic back or joint pain that is not cancer related.

Patients shouldn’t mix methadone with other prescription painkillers or with alcohol, the CDC recommended in the report, and physicians should use state prescription drug monitoring programs to identify patients who are abusing the drug or mixing it with other prescriptions.