References from scientific journals

Morphine metabolites.

Christrup LL. Christrup LL. Acta Anaesthesiol Scand. 1997 Jan;41(1 Pt 2):116-22. doi: 10.1111/j.1399-6576.1997.tb04625.x. Acta Anaesthesiol Scand. 1997. PMID: 9061094 Review.

Morphine is a member of the morphinan-framed alkaloids, which are present in the poppy plant. The drug is soluble in water, but its solubility in lipids is poor. In man, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) are the major metabolites o …
Morphine is a member of the morphinan-framed alkaloids, which are present in the poppy plant. The drug is soluble in water, but its s …

A review of morphine and morphine-6-glucuronide's pharmacokinetic-pharmacodynamic relationships in experimental and clinical pain.

Sverrisdóttir E, Lund TM, Olesen AE, Drewes AM, Christrup LL, Kreilgaard M. Sverrisdóttir E, et al. Eur J Pharm Sci. 2015 Jul 10;74:45-62. doi: 10.1016/j.ejps.2015.03.020. Epub 2015 Apr 7. Eur J Pharm Sci. 2015. PMID: 25861720 Review.

Morphine is a widely used opioid for treatment of moderate to severe pain, but large interindividual variability in patient response and no clear guidance on how to optimise morphine dosage regimen complicates treatment strategy for clinicians. ...This review provid …
Morphine is a widely used opioid for treatment of moderate to severe pain, but large interindividual variability in patient response …

Endogenous morphine and its metabolites in mammals: history, synthesis, localization and perspectives.

Laux-Biehlmann A, Mouheiche J, Vérièpe J, Goumon Y. Laux-Biehlmann A, et al. Neuroscience. 2013 Mar 13;233:95-117. doi: 10.1016/j.neuroscience.2012.12.013. Epub 2012 Dec 21. Neuroscience. 2013. PMID: 23266549 Review.

It is now accepted that endogenous morphine, structurally identical to vegetal morphine-alkaloid, is synthesized by mammalian cells from dopamine. Morphine binds mu opioid receptor and induces antinociceptive effects. ...
It is now accepted that endogenous morphine, structurally identical to vegetal morphine-alkaloid, is synthesized by mammalian …

Morphine-3-glucuronide causes antinociceptive cross-tolerance to morphine and increases spinal substance P expression.

Blomqvist KJ, Viisanen H, Ahlström FHG, Jokinen V, Sidorova YA, Suleymanova I, Rauhala PV, Kalso EA, Lilius TO. Blomqvist KJ, et al. Eur J Pharmacol. 2020 May 15;875:173021. doi: 10.1016/j.ejphar.2020.173021. Epub 2020 Feb 26. Eur J Pharmacol. 2020. PMID: 32112778 Free article.

Morphine-3-glucuronide (M3G), the main metabolite of morphine, has been implicated in the development of tolerance and of opioid-induced hyperalgesia, both limiting the analgesic use of morphine. ...Chronic M3G also induced antinociceptive cross-tolerance to …
Morphine-3-glucuronide (M3G), the main metabolite of morphine, has been implicated in the development of tolerance and of opio …

Morphine-6-glucuronide: morphine's successor for postoperative pain relief?

van Dorp EL, Romberg R, Sarton E, Bovill JG, Dahan A. van Dorp EL, et al. Anesth Analg. 2006 Jun;102(6):1789-97. doi: 10.1213/01.ane.0000217197.96784.c3. Anesth Analg. 2006. PMID: 16717327 Review.

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. ...M6G exhibits a delay in its analgesic effect (blood-effect sit …
In searching for an analgesic with fewer side effects than morphine, examination of morphine's active metabolite, mo …

A Mechanism-Based Forensic Investigation into the Postmortem Redistribution of Morphine.

Gleba J, Kim J. Gleba J, et al. J Anal Toxicol. 2020 Apr 30;44(3):256-262. doi: 10.1093/jat/bkz093. J Anal Toxicol. 2020. PMID: 31776575

The interpretation of postmortem drug levels is complicated by the change in drug blood levels during the postmortem period, a phenomenon known as postmortem drug redistribution. We investigated the postmortem redistribution (PMR) of morphine, morphine-3-glucuronide …
The interpretation of postmortem drug levels is complicated by the change in drug blood levels during the postmortem period, a phenomenon kn …

Determination of Morphine, Fentanyl and Their Metabolites in Small Sample Volumes Using Liquid Chromatography Tandem Mass Spectrometry.

Gleba J, Kim J. Gleba J, et al. J Anal Toxicol. 2020 May 18;44(4):325-330. doi: 10.1093/jat/bkz104. J Anal Toxicol. 2020. PMID: 31897488

We have developed a liquid chromatography tandem mass spectrometry (LC-MS-MS)-based method for the detection of morphine, fentanyl and their metabolites, including morphine-3-glucuronide (M3G), morphine-6-glucuronide (M6G), normorphine, norfentanyl and deuter …
We have developed a liquid chromatography tandem mass spectrometry (LC-MS-MS)-based method for the detection of morphine, fentanyl an …

Role of morphine's metabolites in analgesia: concepts and controversies.

Wittwer E, Kern SE. Wittwer E, et al. AAPS J. 2006 May 26;8(2):E348-52. doi: 10.1007/BF02854905. AAPS J. 2006. PMID: 16796385 Free PMC article. Review.

The metabolites of morphine, morphine-6-glucuronide (M6G) and morphine-3-glucuronide (M3G), have been extensively studied for their contribution to clinical effects following administration of morphine. ...Much attention and effort have been directed a …
The metabolites of morphine, morphine-6-glucuronide (M6G) and morphine-3-glucuronide (M3G), have been extensively studi …

Morphine-6-glucuronide: potency and safety compared with morphine.

van Dorp EL, Morariu A, Dahan A. van Dorp EL, et al. Expert Opin Pharmacother. 2008 Aug;9(11):1955-61. doi: 10.1517/14656566.9.11.1955. Expert Opin Pharmacother. 2008. PMID: 18627332 Review.

The search for opioid analgesics with a better side-effect profile than morphine has led to a morphine metabolites, morphine-6-glucuronide (M6G). ...M6G is an attractive alternative to morphine in the treatment of severe postoperative pain....
The search for opioid analgesics with a better side-effect profile than morphine has led to a morphine metabolites, morphin …

The role of morphine glucuronides in cancer pain.

Mercadante S. Mercadante S. Palliat Med. 1999 Mar;13(2):95-104. doi: 10.1191/026921699678158579. Palliat Med. 1999. PMID: 10474692 Review.

Morphine metabolites are involved in various ways in determining the complex effects of morphine, both favourable and adverse, and may complicate the clinical use of morphine in the treatment of cancer pain. The production and effects of the principal morp …
Morphine metabolites are involved in various ways in determining the complex effects of morphine, both favourable and adverse, …