Dead drug addicts from Copenhagen City and County in 1981 and 1989 respectively were analysed for methadone. Ninety-four cases from 1981 and 70 cases from 1989 were analysed; from 1981, 16% were found positive for methadone, while in 1989, 37% were positive. Methadone alone was found to be the cause of death in 50% more cases in 1989 than in 1981. Only half of the methadone positive dead drug addicts had been in methadone treatment. Morphine and benzodiazepines were the most frequently occurring other substances in both 1981 and 1989. Alcohol was found present in only about 30% of the methadone-positive cases. Medians for methadone whole blood conc. were 0.9 mumol/kg with no alcohol present and 0.5 mumol/kg with alcohol present in addicts dying from methadone. In living persons using methadone, the median was 0.4 mumol methadone/kg whole blood with no alcohol present and 0.3 mumol/kg with alcohol present.