Hydromorphone.

Hydromorphone is a semi-synthetic opioid that has been used widely for acute pain, chronic cancer pain and to a lesser extent, in chronic nonmalignant pain. Its pharmacokinetics and pharmacodynamics have been well studied, including immediate release oral preparations, a variety of slow release oral preparations, as well as administration through intravenous, subcutaneous, epidural, intrathecal and other routes. It is known to be metabolized to analgesically inactive metabolites that have been associated with neuroexcitatory states and other toxicity. There is no evidence that hydromorphone has any greater abuse liability than other opioids. Further research is needed to address remaining areas of uncertainty: equianalgesic ratios; relative risk of toxicity compared with other opioids, its use in nonmalignant pain, and the role of specific hydromorophone metabolites in the development of toxicity, particularly in association with organ failure.