Methadone for Chronic Pain

Methadone use for pain relief has surged over the past two decades. In this time, its special pharmacology has been elucidated which has led to speculation about special properties as well as far greater risks than with other opioid medications. Recently, increasing reports of methadone-related unintended deaths have spurred greater concern about this unique drug. Methadone has many advantages that are now well opposed by many posing serious risks for patients in pain. Advantages include cost, ease of use, and multiple opioid and non-opioid receptor actions. However, risks include metabolic instability related to unique P450 system hepatic clearance that poses drug-drug interactions that differ from other opioids, high protein binding, variable urine clearance, and the potential for cardiac arrhythmia. Thus, this drug that saw a renaissance over the past two decades has now been revealed as more dangerous than previously thought and widely noted to require heightened knowledge and risk management for safe use.