Methadone-related deaths in Palm Beach County.

The authors reviewed cases investigated by the Palm Beach Medical Examiner's Office in which postmortem toxicologic studies indicated the presence of methadone over the period from 1998 to 2002, to examine the role of the drug in these deaths. There were 139 methadone-positive cases, including 75 in which the death was attributed to combined drug toxicity and 23 to methadone toxicity alone. Methadone was most frequently used in conjunction with other prescription or illicit drugs, most commonly benzodiazepines and/or cocaine. There was considerable overlap in the postmortem blood methadone concentrations among the groups. Concentrations ranged from 0.114 mg/L-1.939 mg/L (mean .0559 mg/L) in cases where death was attributed to methadone toxicity; 0.050 mg/L-1.903 mg/L (mean 0.411 mg/L) in cases of combined drug toxicity; 0.069 mg/L-0.644 mg/L (mean 0.224 mg/L) in deaths attributed to other drugs; 0.062 mg/L-1.090 mg/L (mean 0.344 mg/L) among deaths attributed to natural causes and 0.072 mg/L-2.7 mg/L (mean 0.605 mg/L) among deaths due to trauma. The concentrations of methadone detected indicate that it may not be possible to establish a lethal methadone range because some deaths occurred at methadone concentrations below previously reported lethal ranges, and because of the presence of other drugs. Determining the cause of death in methadone-positive cases necessitates correlation with autopsy results and investigative findings.