 Since then, treatment had continued in the cities that participated in the pilot study, until heroin maintenance was permanently included into the national health system in May 2009.A heroin maintenance programme has existed in the United Kingdom (UK) since the 1920s, as drug addiction was seen as an individual health problem.Addiction to opiates was rare in the 1920s and was mostly limited to either middle-class people who had easy access due to their profession, or people who had become addicted as a side effect of medical treatment.