Heroin was introduced as a street drug in the Netherlands in the autumn of 1972. During the first few years, its use was largely limited to the ethnic Dutch population and the route of administration was mainly through intravenous injection. A rapid upsurge in the number of heroin users occurred around 1975 when Surinam, a former Dutch colony in the north of South-America, became independent. At that time, almost half of the Surinamese population emigrated to the Netherlands, settling mainly in Amsterdam, Rotterdam, The Hague and some other urban areas. Young Surinamese men came to play a major role in the street trade of heroin in the big cities, and many of them became heroin users themselves.
In this process, many Surinamese heroin users adhered to their own way of administering the drug, by means of inhalation instead of injection (Korf, 1995), using a technique called "chasing the dragon", or - revealing its Eastern origins - "chinesing", the common name used in the Netherlands. When chasing, the heroin is placed on a piece of aluminum foil, and heated with a cigarette-lighter from below. The heroin fumes are then inhaled by the person through a straw. Originating in Hong Kong in the 1950's, chasing the dragon subsequently spread to other countries in South East Asia in the 1960's and 1970's as well as to the Netherlands in the early 1970's, where it became widespread in the course of the 1980's not only among Surinamese heroin users, but also in the ethnic Dutch heroin using population (Grund and Blanken, 1993; Strang et al., 1997). Currently, chasing the dragon has become an established route of heroin self-administration in not only many Asian countries and the Netherlands, but also in certain parts of Spain (among others Andalucia) and regions in the United Kingdom (among others London) (Strang et al., 1997). As for the Netherlands, epidemiological studies in both treatment and non-treatment samples of Dutch heroin users have consistently indicated that chasing has been the predominant route of heroin self-administration in the Netherlands in the past two decades (Cruts et al., 1997). Currently, it is estimated that 75-90% of the Dutch heroin users predominantly or exclusively inhale their heroin (IVV, 2000; NDM, 2001).
Since the introduction of heroin in the Netherlands, the estimated number of heroin users has increased from 10,000 in 1977 to 20,000 in 1979 and 30,000 in 1983 (Schreuder and Broex, 1998). Since 1984, the total number of heroin addicts in the Netherlands seems to be rather stable, with probably some decrease in the last few years (Hoekstra and Derks, 1991; Van Brussel et al., 1996). The total number of heroin addicts in the Netherlands is currently estimated to be approximately 25.000 (Schreuder and Broex, 1998).
The general epidemiological picture of heroin use in the Netherlands is that of a relatively stable population, with a low incidence of new cases and a low mortality rate (NDM, 2001). This is also reflected in the fact that the mean age of the methadone maintenance population in Amsterdam has increased by approximately 10 months each year since 1984 (the mean age in 1984 was 28.2, whereas the mean age in 1997 amounted to 38.8 years), and in the fact that the percentage of heroin addicts in methadone maintenance who are younger than 26 years dropped from 28% in 1985 to 3% in 1997 (Buster and Reurs, 1997). A similar pattern emerged in Rotterdam, where 28% of the methadone maintenance patients were under the age of 25 years in 1988, whereas only 13% belonged to this age category in 1995 (they had a mean age of 29.3 in 1988 and 34.2 in 1995 (Toet, 1996).
This stable, aging population of heroin addicts is served by a comprehensive treatment and health care system that provides services free of charge and has little or no waiting lists. The system includes various kinds of abstinence oriented treatment facilities (e.g. inpatient and outpatient detoxification, methadone reduction, residential treatment, therapeutic communities) as well as a wide range of facilities which do not focus on abstinence but rather on stabilization and harm reduction (e.g. methadone maintenance, needle and syringe exchange, work projects, sheltered housing, user rooms). It is estimated that, depending on the local circumstances, 65-85% of the heroin addicts in the Netherlands is currently in some form of contact with the treatment system in the course of one year (Gageldonk et al., 1997; Schreuder and Broex, 1998; NDM, 2001).
Patients often begin treatment with the objective of becoming abstinent. In the course of their addiction and treatment career, however, many of those who did not quit the habit switch from abstinence treatment to some kind of harm reduction, primarily through participation in a methadone maintenance program, with or without the additional use of other pharmacological treatments (e.g. triple therapy for AIDS, antidepressants for a comorbid affective disorder) and psychotherapeutic (e.g. counseling, skills training) or psychosocial (e.g. budgeting, housing assistance, work projects) interventions.
Against this background, the medical prescription of heroin is considered as a final treatment option, which is intended only for those chronic heroin addicts who have repeatedly failed in other available treatments, including a state of the art treatment in a methadone maintenance program. In the context of medical heroin prescription, it is therefore crucial to have an adequate understanding of methadone treatment in the Netherlands and the results that have been achieved with it.