This is an updated version of the original review, published in Issue 1, 2002. Some patients with severe cancer pain either do not achieve adequate analgesia with morphine, or suffer intolerable toxicity. For these patients alternatives such as hydromorphone are recommended. However, there appear to be gaps in our understanding of the efficacy of hydromorphone.
The objectives were to evaluate the efficacy of hydromorphone in the management of pain.
Randomised controlled trials (RCTs) which included hydromorphone were sought. The date of the most recent search was November 2006.
RCTs which involved the administration of hydromorphone, for both acute and chronic pain conditions, in adults and children, were included.
Data collection and analysis
A data extraction form was designed for the review. The validity of each trial for inclusion was assessed and a grade was allocated to each study on the basis of allocation concealment with a checklist being used to assess blinding.
Five further trials were added to the original review. The original review reported forty three studies (2725 participants). This review now reports forty eight studies (3510 participants). Approximately half of these studies received a low quality score. In addition, the heterogeneity of the studies precluded a meta-analysis. Of the 48 included studies, 12 (989 participants) involved chronic and 36 (2521 participants) acute pain conditions. Five studies were placebo-controlled. Of the remainder, hydromorphone was compared with other opioids, bupivicaine and with itself, using different formulations. The routes of administration included intravenous, oral, spinal, intramuscular and subcutaneous. Overall, hydromorphone appears to be a potent analgesic. The current limited evidence available suggests that there is little difference between morphine and hydromorphone in terms of analgesic efficacy, adverse effect profile and patient preference. However, as most studies involved small numbers of patients, it is difficult to determine real differences between both drugs. In the context of both acute and chronic pain, the issue of equi-analgesic ratios between morphine and hydromorphone was not resolved.
The studies were varied in terms of quality and methodology. However, the majority demonstrated that hydromorphone is a potent analgesic, that the effects of hydromorphone appear to be dose-related, and that adverse effects are similar to those of other mu opioid receptor agonists. Since the last version of this review, none of the new relevant studies have provided significant additional information.