title: Onset and pattern of substance use in intravenous drug users of an opiate maintenance program.
abstract: OBJECTIVE
  To assess the initiation of substance use of participants in an opiate maintenance program by a cross-sectional survey.
  
  
  METHODS
  Participants (n=184) filled out a questionnaire assessing age at initial substance use and age at onset of regular drug use.
  
  
  RESULTS
  Of 15 substances investigated, alcohol, nicotine, analgesics and marijuana were initiated and consumed regularly before the age of 18 years. Barbiturates, benzodiazepines, cocaine, and opiates were begun later. The time gap between initial and regular use varied depending on the substance. Regular use exceeded 50% for alcohol, benzodiazepines, cocaine, heroin, marijuana and nicotine.
  
  
  CONCLUSIONS
  Specific knowledge about the age of onset and sequence of substances used by drug addicts may help to prevent substance use more age specifically.
authors.affiliation: Outpatient Department of Internal Medicine, University Hospital Basel, Petersgraben 4, CH-4031 Basel, Switzerland.
authors.forename: C
authors.initials: C
authors.lastname: Zinkernagel
authors.forename: M R
authors.initials: MR
authors.lastname: Naef
authors.forename: H C
authors.initials: HC
authors.lastname: Bucher
authors.forename: D
authors.initials: D
authors.lastname: Ladewig
authors.forename: N
authors.initials: N
authors.lastname: Gyr
authors.forename: M
authors.initials: M
authors.lastname: Battegay
mesh_terms: D000328:Adult; D017668:Age of Onset; D005260:Female; D006556:Heroin Dependence / Q000188:drug therapy / Q000503:physiopathology* / Q000523:psychology; D006801:Humans; D008297:Male; D008691:Methadone / Q000627:therapeutic use; D008875:Middle Aged; D009892:Opium / Q000031:analogs & derivatives*; D012647:Self-Assessment; D015819:Substance Abuse, Intravenous / Q000503:physiopathology*; D013557:Switzerland; D013997:Time Factors
chemical_list: D009892:Opium; D008691:Methadone