Oral extended-release oxymorphone: a new choice for chronic pain relief.

Opana ER (oxymorphone extended release [ER]) is a new oral long-acting formulation indicated for the treatment of moderate to severe chronic pain. Because the ER matrix slowly releases oxymorphone over 12 h, consistent plasma levels are produced with low peak-to-trough fluctuations. Oxymorphone ER is the only long-acting opioid that contains oxymorphone, which exhibits some distinct pharmacologic properties compared with most other opioids, including a longer half-life, higher affinity for the micro-opioid receptor, and lack of interaction with the CYPP450 drug-metabolizing system. With a safety and tolerability profile similar to other opioids and documented efficacy in several models of chronic pain (low back, cancer, and osteoarthritis), oxymorphone ER provides a new option for clinicians and patients in the treatment of chronic pain.