title: Potency ratio of hydromorphone and diacetylmorphine in substitution treatment for long-term opioid dependency.
abstract: BACKGROUND
  Data on conversion ratios for switching opioids in substitution treatment are limited.
  
  
  METHODS
  Data were obtained from a randomized controlled trial among long-term opioid-dependent patients conducted in Vancouver and Montreal, Canada. Patients received diacetylmorphine (n = 115) or hydromorphone (n = 25) on a double-blind basis, on a 1:3 potency ratio with individually adjusted dosage, both injectable.
  
  
  RESULTS
  Average daily dosages of hydromorphone and diacetylmorphine prescribed were 212.6 mg and 454.0 mg, respectively; potency ratio was 1:2.0-2.2 at different dose ranges.
  
  
  CONCLUSIONS
  Studies using hydromorphone as a diacetylmorphine equivalent should consider the ratio found in this study to achieve equipotency and maintain the blinding.
authors.affiliation: School of Population and Public Health, University of British Columbia, Canada.
authors.forename: Eugenia
authors.initials: E
authors.lastname: Oviedo-Joekes
authors.forename: David C
authors.initials: DC
authors.lastname: Marsh
authors.forename: Daphne
authors.initials: D
authors.lastname: Guh
authors.forename: Suzanne
authors.initials: S
authors.lastname: Brissette
authors.forename: Martin T
authors.initials: MT
authors.lastname: Schechter
mesh_terms: D000701:Analgesics, Opioid / Q000008:administration & dosage*; D002170:Canada; D004311:Double-Blind Method; D003932:Heroin / Q000008:administration & dosage*; D006801:Humans; D004091:Hydromorphone / Q000008:administration & dosage*; D007267:Injections; D058850:Opiate Substitution Treatment; D009293:Opioid-Related Disorders / Q000150:complications / Q000188:drug therapy*; D013375:Substance Withdrawal Syndrome / Q000209:etiology / Q000517:prevention & control*; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000701:Analgesics, Opioid; D003932:Heroin; D004091:Hydromorphone