Methadone Drug Interactions
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.
