Methadone Use for Pain Management Blamed for Increase in Deaths

Increased prescribing of methadone for pain management and a lack of prescriber knowledge about its pharmacological risks are the main contributing factors to the spike of deaths associated with methadone overdose in recent years, a government report has found.

A fivefold increase in methadone-associated overdose deaths from 1999 to 2005, as reported by the Centers for Disease Control and Prevention, has caused growing concern among public-health experts. The Government Accountability Office (GAO) conducted an investigation on the causes of this trend and government efforts to curb it and released the findings in a report on March 26.

One of the key factors in the spike in methadone-associated deaths is the rising number of methadone prescriptions intended for pain management since the late 1990s, after the abuse and deaths associated with OxyContin were widely publicized, the report concluded. The increased prescribing may have led to easier availability for diversion and misuse, since methadone prescribed for pain is dispensed like other Schedule II narcotics and not restricted to methadone clinics registered by the Drug Enforcement Administration (DEA). In those clinics the medication is directly administered. “Methadone prescriptions for pain management grew ... nearly eightfold” from 1998 to 2006, the report found. Meanwhile, the amount of methadone dispensed by opioid-addiction treatment programs increased far more slowly.

The increased use of methadone for pain management carries additional safety risks compared with its use by addiction specialists, because many health care professionals are unfamiliar with the pharmacological properties of methadone that set it apart from other opioid medications, the report noted. Methadone has a slow onset of action as well as slow elimination and remains in the body long after the pain-relief effect wears off.

Some organizations and experts told the GAO that many practitioners lack adequate training in managing pain with methadone. If not fully warned of the risks, patients may take more than the appropriate dosage or take methadone with other narcotics, causing accumulation of the medication and leading to respiratory suppression and overdose.

In addition, the DEA and other agencies indicated to GAO that increased diversion and abuse of methadone appear to have contributed to the increased deaths. This may be part of a national trend of increased prescription-drug abuse in general, especially among younger populations, in recent years.

The GAO noted a number of public-health efforts that were conducted by the federal government and five states to reduce and prevent methadone abuse, overdose, and deaths, and these were reviewed for the report: Florida, Kentucky, Maine, New Mexico, and West Virginia.

For example, the Substance Abuse and Mental Health Services Administration has given a $1.5 million grant to the American Society of Addiction Medicine to establish a Physician Clinical Support System to educate prescribers about the safe use of methadone for pain management and addiction treatment. Other educational initiatives through public and private organizations have been or are being developed for health care professionals and consumers. Some experts warned, however, that too much emphasis on methadone alone could“ unintentionally shift similar problems to a different drug,” according to the report.

Following a request by the Food and Drug Administration in November 2006, the labeling of methadone was revised and now carries strengthened safety warnings and dosage guidelines, including suggesting a maximum daily dose of 30 mg for treating pain, the GAO report stated. On March 3 the agency and manufacturers of certain opioid products, including methadone, held a joint meeting to develop a “risk evaluation and mitigation strategy” to monitor these medications continuously and ensure that they are used safely.

“Methadone-Associated Overdose Deaths: Factors Contributing to Increased Deaths and Efforts to Prevent Them” is posted at<www.gao.gov/cgi-bin/getrpt?GAO-09-341>.▪