"The number of deaths with presence of methadone in the blood has tripled in Sweden during the period 2006-2008. In the same period, there has been a rapid expansion of methadone treatment. In 2005, the regulations on medically assisted substitution treatment were changed in Sweden. The previous restrictions on the number of people who were allowed to participate in treatment at the same time were removed. The number of new treatment units increased tenfold when a number of new programmes started throughout the country (Fugelstad et al., 2010). In autumn 2010 there were 64 units that provided pharmaceutically assisted maintenance treatment in Sweden (Swedish National Institute of Public Health, 2010).
"A forensic medical examination of the methadone related deaths shows that the majority involved mixed intoxication where the methadone played an important role. As the Swedish prescription register shows that 80 per cent of the deceased persons had not obtained their methadone from any legal sources, methadone programmes or pain relief treatment, leakage from methadone treatment appears to be a possible but minor source (Fugelstad et al., 2010)."

Source

Swedish National Institute of Public Health. "2012 National Report (2011 data) To the EMCDDA by the Reitox National Focal Point: Sweden: New Development, Trends and in-depth information on selected issues." Östersund: Swedish National Institute of Public Health, 2012, p. 56.
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