Methadone Law Blog

Researchers at Oregon Health & Science University have concluded that methadone is a possible cause of sudden cardiac death. The study determined that sudden cardiac death could be caused by methadone even when it was taken at therapeutic levels for relief of chronic pain or drug addiction withdrawal. The study's findings were based on an evaluation of all sudden cardiac deaths in the greater Portland, Oregon metropolitan area between 2002 and 2006 where detailed autopsies were performed.

The analysis was based on a comparison of two case groups. One group consisted of 22 sudden cardiac deaths in which toxicology screens turned up 1 mg or less of methadone which is defined as therapeutic level. The cases were then compared to a second group of 106 cases where no evidence of methadone was found. In the first case group, 17 of the 22 subjects had no significant cardiac abnormalities. On the other hand, 60% of the case group where no methadone is present had identifiable evidence of cardiac disease or structural abnormalities. "The unexpectedly high proportion of otherwise unexplained sudden deaths in the therapeutic methadone group points to a significant contribution of this drug towards the occurrence of sudden cardiac death among these patients" said Sumeet Chugh, M.D. lead investigator, Director of OHSU's Cardiac Arrhythmia Center, and Associate Professor of Cardiovascular Medicine in the OHSU School of Medicine. Individual case reports have linked methadone to a rare ventricular arrhythmia, known as torsade de pointes, which can degenerate into ventricular fibrillation leading to sudden death in the absence of medical intervention.

The researchers have proposed that a large prospective evaluation of methadone therapy be undertaken since a sizable and growing number of people are utilizing methadone for both pain management and drug addiction.

Posted by Michael G. Donahue, III | Permalink | Email This Post

Posted In: Drug Interaction , News , Research

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In an article prescribing methadone safely, Dr. Lynn R. Webster discusses the fact that methadone has been implicated to a disproportionate degree in many overdose deaths recorded across the country. He noted that physicians don’t have all the answers as to why these deaths are occurring, but some tie to the fact that methadone is prescribed for pain. The United States Substance Abuse and Mental Health Services Administration (SAMHSA) has reached a similar conclusion.

One or two causes are usually to blame when pain treatment goes wrong. The medications are either being prescribed incorrectly or are being consumed inappropriately. While it is recognized that patient noncompliance is common and almost all clinicians should be familiar with it. With painkillers, patients often over-consume their pain medication to try to counteract the stress they are experiencing in their lives. They want their pain to be eliminated rather than just controlled. Many patients believe that if two tablets are good, a third must be better. While this may not be dangerous with some medication, it can have a deadly result with methadone. Further, patients mix methadone with other medications and/or with alcohol. This is a cocktail which could easily lead to death. Patients must be instructed to follow all medical directions to the letter when consuming methadone or any other opiate.

Physicians also make errors when prescribing opiates, particularly methadone. This may be attributable to widely available conversion tables. The starting dose is critical and tolerance by a patient cannot be assumed.

It seems the clinicians who prescribe methadone for pain as well as the patients that are taking methadone may be underestimating the risk of respiratory or depression that is associated with the drug. Methadone is eliminated from the body at a slower rate than other medications and has a half life which averages around 48 hours. Because it lasts so long, methadone is particularly prone to dangerous drug interactions. The pharmacologic properties of methadone require a conservative approach to even the most opiate-tolerant patients. Careful monitoring of the patients response is key.

Posted by Michael G. Donahue, III | Permalink | Email This Post

Posted In: Drug Interaction , Pain Management

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When a person takes medication there is always a risk to how they new medication will interact with other drugs. In the case of methadone, there are more than 100 substances that can interact in some fashion to affect a patient’s response. These substances include prescription medications, illicit drugs, and even “over the counter” (OTC) products which would seem to be benign. This is a significant issue, because many individuals in methadone maintenance treatment (MMT) have co-occurring physical and/or mental disorders requiring multiple medications.

Drugs are broken down, or metabolized, by chemical reactions into molecules that can more easily be eliminated. One of the primary ways in which the body metabolizes drugs involves proteins. Proteins facilitate these chemical reactions, allowing the medication to accomplish its purpose. These proteins are known as CYP450 enzymes, and there are more than 28 CYP enzymes encoded to 57 different human genes.

There are 3 different, primary ways in which substances interact with the enzyme system:

• 1) by acting as a substrate


• 2) through inhibition


• 3) through induction

A substrate is any drug metabolized by one or more CYP enzymes, an inhibitor slows the metabolism of substrate drugs, and an inducer boosts the metabolism of substrate drugs. Inhibitors may cause an excessively high drug level and related toxic effects, while and inducer may cause a lower than expected level of the substrate drug.

For a detailed list of medications, illicit drugs and other substances that may cause a drug interaction with methadone, see Addiction Treatment Forum, 3rd Edition, November 2005 Revision/Update by Stewart B. Leavitt, Ph.D. (PDF)

Posted by John A. Sakson | Permalink | Email This Post

Posted In: Drug Interaction

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