"Substitution treatment is the predominant treatment option for opioid users in Europe. It is generally provided in specialist outpatient settings, though in some countries it is also available in inpatient settings, and is increasingly provided in prisons (20). In addition, office-based general practitioners, often in shared-care arrangements with specialist centres, increasingly play a role. Opioid substitution is available in all EU Member States and in Croatia, Turkey and Norway (21). Overall, it is estimated that there were about 710 000 substitution treatments in Europe in 2010. Compared with 2009, the number of clients in substitution treatment increased in most countries, though Spain and Slovakia report small decreases (22)."

Source

European Monitoring Centre for Drugs and Drug Addiction, "Annual report 2012: the state of the drugs problem in Europe" (Luxembourg: Publications Office of the European Union, November 2012), Catalog No. TDAC12001ENC, doi:10.2810/64775, p. 41.
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