Oxymorphone Hydrochloride

Oxymorphone is a typical mu-opioid agonist that is effective in both immediate-release and extended-release oral formulations. The mechanism of action involves binding to mu-opioid receptors in the central nervous system, where it alters the perception of and response to painful stimuli while producing generalized central nervous system depression. Oxymorphone is more lipid soluble than morphine, resulting in a rapid onset of action when given in tablet formulation, with a duration of action of approximately 4-6 hours in immediate-release and 12 hours in extended-release preparations. Oral oxymorphone provides excellent pain relief for significant pain including acute postoperative pain, chronic arthritis pain, chronic low back pain, and chronic cancer pain. Multiple double-blind, prospective, placebo-controlled clinical trials have demonstrated the clinical efficacy and safety of this oral opioid formulation.

Fig. 1 Mean single-dose and steady-state plasma concentrations of oxymorphone IR. (Sloan P. 2008)