Morphine‐6‐glucuronide: Actions and mechanisms

@article{Kilpatrick2005Morphine6glucuronideAA,
  title={Morphine‐6‐glucuronide: Actions and mechanisms},
  author={Gavin Kilpatrick and Terry W. Smith},
  journal={Medicinal Research Reviews},
  year={2005},
  volume={25}
}
Morphine‐6‐glucuronide (M6G) appears to show equivalent analgesia to morphine but to have a superior side‐effect profile in terms of reduced liability to induce nausea and vomiting and respiratory depression. The purpose of this review is to examine the evidence behind this statement and to identify the possible reasons that may contribute to the profile of M6G. The vast majority of available data supports the notion that both M6G and morphine mediate their effects by activating the µ‐opioid… 
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TLDR
A detailed overview of the published human population pharmacokinetic-pharmacodynamic studies for morphine analgesia in addition to basic drug disposition and pharmacological properties of morphine and its analgesic active metabolite, morphine-6-glucuronide, that may help identify future covariates are provided.
Conditioned place preference induced by morphine and morphine-6-glucuronide in mice
TLDR
Morphine-6-glucuronide and M6G demonstrated comparable reward effects, at doses that differed depending on which compartment the mice were conditioned in, and M3G showed a tendency to exhibit aversive properties.
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It is speculated that M6G may exhibit analgesic effects while causing fewer adverse effects than morphine, and may be contemplated as an analgesic for short term postoperative analgesia, especially for intrathecal analgesic therapy.
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