[Fatal methadone poisoning: observations at the CHU of Liege]

All methadone-associated deaths from October 2002 to April 2005 are analysed. A regular increase in these fatal intoxications has been recorded, in Belgium as in other countries, due, in particular, to an intensified prescription of this product, of which illicit use as street dope becomes problematic. Over the 30 months period covered by the study, 26 deaths related to methadone were listed, of which 3 occurred in accidental circumstances. In the other 23 cases, methadone can be found, yet always associated with psychotropic substances, mainly benzodiazepines (18 cases), narcotics (15 cases) and finally alcohol (5 cases). Based upon the nature of the products combined with methadone, records have been divided in two groups: In the first group (17 observations), xenobiotics at (infra)therapeutic levels are detected. In the other group (6 observations), xenobiotics at high and toxic levels are detected. Blood methadone concentrations are not so different between the 2 groups of individuals since the median values and the extreme values are worth respectively 308, and 110-11300 microg/L, for the first group and 776 and 93-2080 microg/L for the second group. There is thus an important overlap between the therapeutic blood methadone concentrations (150-400 microg/L) and blood concentrations observed in fatalities.Thus, it is necessary that all information and post-mortem results must be examined in a critical way to identify and justify cause of the death.