title: Use of other opioids during methadone therapy: a population-based study.
abstract: OBJECTIVE
  To determine the extent to which other opioids are prescribed to patients receiving methadone in Ontario, Canada.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Ontario, Canada from 1 April 2003 to 31 March 2010.
  
  
  METHODS
  We studied patients aged 15-64 years with publically funded drug coverage who received at least 30 days of continuous methadone maintenance therapy (MMT).
  
  
  METHODS
  The proportion of patients who received more than 7 days of a non-methadone opioid during MMT. A secondary analysis examined the extent to which non-methadone opioids were prescribed by physicians or dispensed by pharmacies not involved in a patient's MMT.
  
  
  RESULTS
  Among 18,759 patients treated with methadone, 3456 (18.4%) received at least one prescription for non-methadone opioids of more than 7 days' duration. In this group, the median number of non-methadone opioid prescriptions dispensed per year was 11.9 (interquartile range 4.1-25.0). The most frequently prescribed opioids were codeine and oxycodone. Of the 73,520 non-methadone opioid prescriptions of more than 7 days' duration, nearly half (45.8%) originated from non-MMT prescribers and pharmacies.
  
  
  CONCLUSIONS
  Many patients receiving methadone maintenance therapy in Ontario receive overlapping prescriptions for other opioids, often for extended periods. The associated prescribing patterns suggest that many such prescriptions may be duplicitous. The prescribing and dispensing of non-methadone opioids to patients receiving methadone maintenance therapy is likely to be observed in jurisdictions outside Ontario, Canada.
authors: Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada. paul_kurdyak@camh.net
authors: Paul
authors: P
authors: Kurdyak
authors: Tara
authors: T
authors: Gomes
authors: Zhan
authors: Z
authors: Yao
authors: Muhammad M
authors: MM
authors: Mamdani
authors: Chelsea
authors: C
authors: Hellings
authors: Benedikt
authors: B
authors: Fischer
authors: Jürgen
authors: J
authors: Rehm
authors: Ahmed M
authors: AM
authors: Bayoumi
authors: David N
authors: DN
authors: Juurlink
mesh_terms: D000293:Adolescent; D000328:Adult; D000701:Analgesics, Opioid / Q000600:supply & distribution / Q000627:therapeutic use*; D011307:Drug Prescriptions / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D008691:Methadone / Q000627:therapeutic use*; D008875:Middle Aged; D009294:Narcotics / Q000627:therapeutic use*; D009864:Ontario; D009293:Opioid-Related Disorders / Q000534:rehabilitation*; D055553:Prescription Drugs / Q000627:therapeutic use*; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D000701:Analgesics, Opioid; D009294:Narcotics; D055553:Prescription Drugs; D008691:Methadone