Morphine-6-Glucuronide: Morphine's Successor for Postoperative Pain Relief?

@article{vanDorp2006Morphine6GlucuronideMS,
  title={Morphine-6-Glucuronide: Morphine's Successor for Postoperative Pain Relief?},
  author={Eveline L. A. van Dorp and Raymonda R Romberg and Elise Y. Sarton and James G. Bovill and Albert Dahan},
  journal={Anesthesia \& Analgesia},
  year={2006},
  volume={102},
  pages={1789-1797}
}
In searching for an analgesic with fewer side effects than morphine, examination of morphine's active metabolite, morphine-6-glucuronide (M6G), suggests that M6G is possibly such a drug. In contrast to morphine, M6G is not metabolized but excreted via the kidneys and exhibits enterohepatic cycling, as it is a substrate for multidrug resistance transporter proteins in the liver and intestines. M6G exhibits a delay in its analgesic effect (blood-effect site equilibration half-life 4–8 h), which… 
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