Opioid Metabolism and Effects of Cytochrome P450

Over the past 10–20 years researchers have enhanced our understanding of the metabolism and risk of drug interactions of numerous medications utilized by patients with pain conditions. Pain patients often are prescribed multiple medications that can inhibit or induce specific cytochrome P450 (CYP450) enzymes. This review will focus on the effect of the CYP450 enzyme system metabolism on opioid agents codeine, fentanyl, hydrocodone, hydromorphone, methadone, morphine, oxycodone, and oxymorphone, as well as the potential effect of these opioids on the metabolism of other medications and vice versa.