Potency ratio of hydromorphone and diacetylmorphine in substitution treatment for
long-term opioid dependency.
Author(s): Oviedo-Joekes E, Marsh DC, Guh D, Brissette S, Schechter MT.
Affiliation(s): School of Population and Public Health, University of British Columbia, Canada.
Publication date & source: 2011, J Opioid Manag. , 7(5):371-6
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