Relationships Among Morphine Metabolism, Pain and Side Effects During Long-Term Treatment: An Update

摘要: The two metabolites of morphine, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G), have been studied intensively in animals humans during the past 30 years order to elucidate their precise action possible contribution desired effects side seen after morphine administration. M3G M6G are formed by glucuronidation, mainly liver, excreted kidneys. found cerebrospinal fluid single as well multiple doses morphine. binds opioid receptors, animal studies demonstrated that may be a more potent analgesic than Results from human regarding effect not unanimous. potency ratio between systemic has settled, but is probably lower previously assumed. Hitherto, only few evidence for contributory overall observed Several administration accompanied fewer milder degree opioid-like administration, most used displays very low affinity receptors no activity. Animal shown antagonize M6G, this. also connected certain neurotoxic symptoms, such hyperalgesia, allodynia myoclonus, which or high animals. symptoms reported sporadically treated primarily with role eliciting fully elucidated.