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Noufal Y, Kringel D, Toennes SW, Dudziak R, Lötsch J. Pharmacological data science perspective on fatal incidents of morphine treatment. Pharmacol Ther 2023; 241:108312. [PMID: 36423714 DOI: 10.1016/j.pharmthera.2022.108312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 11/10/2022] [Accepted: 11/14/2022] [Indexed: 11/23/2022]
Abstract
Morphine prescribed for analgesia has caused drug-related deaths at an estimated incidence of 0.3% to 4%. Morphine has pharmacological properties that make it particularly difficult to assess the causality of morphine administration with a patient's death, such as its slow transfer between plasma and central nervous sites of action and the existence of the active metabolite morphine-6-glucuronide with opioid agonistic effects, Furthermore, there is no well-defined toxic dose or plasma/blood concentration for morphine. Dosing is often adjusted for adequate pain relief. Here, we summarize reported deaths associated with morphine therapy, including associated morphine exposure and modulating patient factors such as pharmacogenetics, concomitant medications, or comorbidities. In addition, we systematically analyzed published numerical information on the stability of concentrations of morphine and its relevant metabolites in biological samples collected postmortem. A medicolegal case is presented in which the causality of morphine administration with death was in dispute and pharmacokinetic modeling was applied to infer the administered dose. The results of this analytical review suggest that (i) inference from postmortem blood concentrations to the morphine dose administered has low validity and (ii) causality between a patient's death and the morphine dose administered remains a highly context-dependent and collaborative assessment among experts from different medical specialties.
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Affiliation(s)
- Yazan Noufal
- Goethe-University, Institute of Clinical Pharmacology, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
| | - Dario Kringel
- Goethe-University, Institute of Clinical Pharmacology, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
| | - Stefan W Toennes
- Goethe-University, University Hospital Frankfurt, Institute of Legal Medicine, Kennedyallee 104, 60596 Frankfurt am Main, Germany
| | - Rafael Dudziak
- Goethe-University, University Hospital Frankfurt, Department of Anesthesiology, Intensive Care Medicine and Pain Therapy, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany
| | - Jörn Lötsch
- Goethe-University, Institute of Clinical Pharmacology, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany; Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, Theodor-Stern-Kai 7, 60596 Frankfurt am Main, Germany.
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2
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Gabel F, Hovhannisyan V, Berkati AK, Goumon Y. Morphine-3-Glucuronide, Physiology and Behavior. Front Mol Neurosci 2022; 15:882443. [PMID: 35645730 PMCID: PMC9134088 DOI: 10.3389/fnmol.2022.882443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 04/26/2022] [Indexed: 11/13/2022] Open
Abstract
Morphine remains the gold standard painkiller available to date to relieve severe pain. Morphine metabolism leads to the production of two predominant metabolites, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G). This metabolism involves uridine 5′-diphospho-glucuronosyltransferases (UGTs), which catalyze the addition of a glucuronide moiety onto the C3 or C6 position of morphine. Interestingly, M3G and M6G have been shown to be biologically active. On the one hand, M6G produces potent analgesia in rodents and humans. On the other hand, M3G provokes a state of strong excitation in rodents, characterized by thermal hyperalgesia and tactile allodynia. Its coadministration with morphine or M6G also reduces the resulting analgesia. Although these behavioral effects show quite consistency in rodents, M3G effects are much more debated in humans and the identity of the receptor(s) on which M3G acts remains unclear. Indeed, M3G has little affinity for mu opioid receptor (MOR) (on which morphine binds) and its effects are retained in the presence of naloxone or naltrexone, two non-selective MOR antagonists. Paradoxically, MOR seems to be essential to M3G effects. In contrast, several studies proposed that TLR4 could mediate M3G effects since this receptor also appears to be essential to M3G-induced hyperalgesia. This review summarizes M3G’s behavioral effects and potential targets in the central nervous system, as well as the mechanisms by which it might oppose analgesia.
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Affiliation(s)
- Florian Gabel
- CNRS UPR 3212, Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique and University of Strasbourg, Strasbourg, France
| | - Volodya Hovhannisyan
- CNRS UPR 3212, Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique and University of Strasbourg, Strasbourg, France
| | - Abdel-Karim Berkati
- CNRS UPR 3212, Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique and University of Strasbourg, Strasbourg, France
| | - Yannick Goumon
- CNRS UPR 3212, Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique and University of Strasbourg, Strasbourg, France
- SMPMS, Mass Spectrometry Facilities of the CNRS UPR 3212, Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique, Strasbourg, France
- *Correspondence: Yannick Goumon,
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3
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Zhang F, Trent Magruder J, Lin YA, Crawford TC, Grimm JC, Sciortino CM, Wilson MA, Blue ME, Kannan S, Johnston MV, Baumgartner WA, Kannan RM. Generation-6 hydroxyl PAMAM dendrimers improve CNS penetration from intravenous administration in a large animal brain injury model. J Control Release 2017; 249:173-182. [PMID: 28137632 DOI: 10.1016/j.jconrel.2017.01.032] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 01/03/2017] [Accepted: 01/26/2017] [Indexed: 11/28/2022]
Abstract
Hypothermic circulatory arrest (HCA) provides neuroprotection during cardiac surgery but entails an ischemic period that can lead to excitotoxicity, neuroinflammation, and subsequent neurologic injury. Hydroxyl polyamidoamine (PAMAM) dendrimers target activated microglia and damaged neurons in the injured brain, and deliver therapeutics in small and large animal models. We investigated the effect of dendrimer size on brain uptake and explored the pharmacokinetics in a clinically-relevant canine model of HCA-induced brain injury. Generation 6 (G6, ~6.7nm) dendrimers showed extended blood circulation times and increased accumulation in the injured brain compared to generation 4 dendrimers (G4, ~4.3nm), which were undetectable in the brain by 48h after final administration. High levels of G6 dendrimers were found in cerebrospinal fluid (CSF) of injured animals with a CSF/serum ratio of ~20% at peak, a ratio higher than that of many neurologic pharmacotherapies already in clinical use. Brain penetration (measured by drug CSF/serum level) of G6 dendrimers correlated with the severity of neuroinflammation observed. G6 dendrimers also showed decreased renal clearance rate, slightly increased liver and spleen uptake compared to G4 dendrimers. These results, in a large animal model, may offer insights into the potential clinical translation of dendrimers.
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Affiliation(s)
- Fan Zhang
- Center for Nanomedicine/Wilmer Eye Institute, Department of Ophthalmology, The Johns Hopkins School of Medicine, Baltimore, MD 21287, United States; Department of Materials Science and Engineering, The Johns Hopkins University, Baltimore, MD, 21218, United States
| | - J Trent Magruder
- Division of Cardiac Surgery, Department of Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Yi-An Lin
- Center for Nanomedicine/Wilmer Eye Institute, Department of Ophthalmology, The Johns Hopkins School of Medicine, Baltimore, MD 21287, United States
| | - Todd C Crawford
- Division of Cardiac Surgery, Department of Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Joshua C Grimm
- Division of Cardiac Surgery, Department of Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Christopher M Sciortino
- Division of Cardiac Surgery, Department of Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Mary Ann Wilson
- Hugo W. Moser Research Institute at Kennedy Krieger Inc., Baltimore, MD 21205, United States; Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Mary E Blue
- Hugo W. Moser Research Institute at Kennedy Krieger Inc., Baltimore, MD 21205, United States; Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Sujatha Kannan
- Hugo W. Moser Research Institute at Kennedy Krieger Inc., Baltimore, MD 21205, United States; Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Michael V Johnston
- Hugo W. Moser Research Institute at Kennedy Krieger Inc., Baltimore, MD 21205, United States; Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - William A Baumgartner
- Division of Cardiac Surgery, Department of Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States.
| | - Rangaramanujam M Kannan
- Center for Nanomedicine/Wilmer Eye Institute, Department of Ophthalmology, The Johns Hopkins School of Medicine, Baltimore, MD 21287, United States.
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4
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Lee KA, Ganta N, Horton JR, Chai E. Evidence for Neurotoxicity Due to Morphine or Hydromorphone Use in Renal Impairment: A Systematic Review. J Palliat Med 2016; 19:1179-1187. [PMID: 27399959 DOI: 10.1089/jpm.2016.0101] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Opioids are the mainstay of pain control for patients with chronic pain. Often, opioids with reported active metabolites, such as morphine and hydromorphone, are thought to increase the risk of neurotoxicity in renal impairment. OBJECTIVES To identify and assess the quality of evidence for neurotoxic effects in patients with renal impairment receiving morphine or hydromorphone. METHODS Systematic searches were conducted of the following databases from inception to December 2015: MEDLINE, CINAHL, EMBASE, in addition to hand-searching relevant review articles' citations. Studies were included if they reported neurotoxic effects of either morphine or hydromorphone for chronic or malignant pain in patients with renal impairment. Review articles and case reports were excluded. Narrative review was undertaken. The Grading of Recommendations, Assessment, Development and Evaluation approach was used to assess study quality. RESULTS Six original articles, three prospective and three retrospective studies were identified and assessed. No relevant randomized clinical trials were identified. CONCLUSIONS Although morphine and hydromorphone use may be associated with neurotoxic effects in patients with renal impairment, current evidence consists of very low-quality studies with conflicting findings. Clinicians may consider using either morphine or hydromorphone in mild-to-moderate renal impairment, while closely monitoring for neurotoxic effects, particularly when used in high doses and for extended duration.
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Affiliation(s)
- Kathleen A Lee
- 1 Department of Psychosocial Oncology and Palliative Care, Dana-Farber Cancer Institute , Boston, Massachusetts
| | - Niharika Ganta
- 2 Division of General Internal Medicine, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania , Philadelphia, Pennsylvania
| | - Jay R Horton
- 3 Department of Geriatrics and Palliative Medicine, Icahn School of Medicine at Mount Sinai , New York, New York
| | - Emily Chai
- 3 Department of Geriatrics and Palliative Medicine, Icahn School of Medicine at Mount Sinai , New York, New York
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5
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Chaves C, Gómez-Zepeda D, Auvity S, Menet MC, Crété D, Labat L, Remião F, Cisternino S, Declèves X. Effect of Subchronic Intravenous Morphine Infusion and Naloxone-Precipitated Morphine Withdrawal on P-gp and Bcrp at the Rat Blood-Brain Barrier. J Pharm Sci 2016; 105:350-8. [PMID: 26554626 DOI: 10.1002/jps.24697] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2015] [Revised: 09/24/2015] [Accepted: 09/30/2015] [Indexed: 12/14/2022]
Abstract
Chronic morphine regimen increases P-glycoprotein (P-gp) and breast cancer-resistance protein (Bcrp) expressions at the rat blood–brain barrier (BBB) but what drives this effect is poorly understood. The objective of this study is to assess subchronic continuous morphine infusion and naloxone-precipitated morphine withdrawal effects on P-gp/Bcrp contents and activities at the rat BBB. Rats were treated either with (i) a continuous i.v. morphine for 120 h, (ii) escalating morphine dosing (10-40 mg/kg, i.p., 5 days), (iii) a chronic morphine regimen (10 mg/kg s.c., 5 days) followed by a withdrawal period (2 days) and treatment for 3 additional days. Animal behavior was assessed after naloxone-precipitated withdrawal (1 mg/kg, s.c.). P-gp/Bcrp expressions and activities were determined in brain microvessels by qRT-PCR, Western blot, UHPLC–MS/MS, and in situ brain perfusion of P-gp or Bcrp substrates. Results show continuous i.v. morphine did not change P-gp/Bcrp protein levels in rat brain microvessels, whereas naloxone-precipitated withdrawal after escalating or chronic morphine dose regimen increased Mdr1a and Bcrp mRNA levels by 1.4-fold and 2.4-fold, respectively. Conversely, P-gp/Bcrp protein expressions remained unchanged after naloxone administration, and brain uptake of [3H]-verapamil (P-gp) and [3H]-mitoxantrone (Bcrp) was not altered. The study concludes subchronic morphine infusion and naloxone-precipitated morphine withdrawal have poor effect on P-gp/Bcrp levels at the rat BBB.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics
- ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism
- ATP Binding Cassette Transporter, Subfamily G, Member 2
- ATP-Binding Cassette Transporters/genetics
- ATP-Binding Cassette Transporters/metabolism
- Analgesics, Opioid/administration & dosage
- Analgesics, Opioid/blood
- Analgesics, Opioid/pharmacology
- Animals
- Blood-Brain Barrier/drug effects
- Blood-Brain Barrier/metabolism
- Cerebral Cortex/drug effects
- Cerebral Cortex/metabolism
- Infusions, Intravenous
- Male
- Morphine/administration & dosage
- Morphine/blood
- Morphine/pharmacology
- Naloxone/pharmacology
- Narcotic Antagonists/pharmacology
- Proteomics
- Rats
- Rats, Sprague-Dawley
- Substance Withdrawal Syndrome/metabolism
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6
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Klimas R, Mikus G. Morphine-6-glucuronide is responsible for the analgesic effect after morphine administration: a quantitative review of morphine, morphine-6-glucuronide, and morphine-3-glucuronide. Br J Anaesth 2014; 113:935-44. [DOI: 10.1093/bja/aeu186] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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7
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Andersen G, Sjøgren P, Hansen SH, Jensen NH, Christrup L. Pharmacological consequences of long-term morphine treatment in patients with cancer and chronic non-malignant pain. Eur J Pain 2012; 8:263-71. [PMID: 15109977 DOI: 10.1016/j.ejpain.2003.09.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2003] [Accepted: 09/22/2003] [Indexed: 11/19/2022]
Abstract
BACKGROUND In patients with pain of malignant origin morphine may be administered in high and often increasing doses during extended periods of time. In patients with chronic pain of non-malignant origin morphine may be an important remedy, and in these cases the goal is to keep the morphine dose stable. The pharmacokinetic as well as the pharmacodynamic consequences of long-term morphine treatment with special reference to the two most important metabolites of morphine morphine-6-glucuronide (M-6-G) and morphine-3-glucuronide (M-3-G) remain to be settled. METHODS Assessments for pain, sedation and other morphine induced side effects were made several times for 19 cancer patients treated with changing doses of oral sustained release (SR) morphine and twice for 17 non-cancer patients treated with stable doses of SR morphine. Blood samples were obtained simultaneously and analysed for contents of morphine, M-3-G and M-6-G by high-performance liquid chromatography (HPLC). RESULTS Significant correlations were found between the daily dose of SR morphine and plasma morphine (r = 0.469, p < 0.01), plasma M-6-G (r = 0.677, p < 0.01), and plasma M-3-G ((r = 0.827, p < 0.01), in the cancer patient group, but only between the daily dose of SR morphine and plasma M-3-G (0.662, p < 0.01) and plasma M-6-G (0.571, p < 0.01) in the non-cancer patient group. Normalised M-3-G/M and M-6-G/M ratios for the cancer patient group were independent of duration of treatment and daily dose of SR morphine. Likewise in the non-cancer patient group duration of treatment did not influence the metabolite ratios. Correlations between pain score and plasma morphine, M-6-G and M-6-G/M were weak in the cancer patient as well as in the non-cancer patient group making it impossible to draw any conclusion regarding the potential contributory analgesic effect of M-6-G. Dryness of the mouth was the most frequent adverse effect reported in the non-cancer as well as the cancer patient group. In the latter group patients complaining of dryness of the mouth had significantly higher plasma morphine and M-6-G concentrations than patients who did not suffer from this side effect. This difference persisted (or was close to significance) when excluding patients receiving antidepressants. CONCLUSION In the cancer patient group neither dose nor treatment period seems to influence morphine glucuronidation. Likewise in the non-cancer patient group receiving stable doses of morphine duration of treatment does not seem to influence morphine glucuronidation. Dryness of the mouth was positively correlated to high plasma concentrations of morphine and M-6-G.
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Affiliation(s)
- Gertrud Andersen
- Multidisciplinary Pain Centre, Herlev University Hospital, Herlev 2730, Denmark.
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8
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Oosten A, Oldenmenger W, van Zuylen C, Schmitz P, Bannink M, Lieverse P, Bromberg J, van der Rijt C. Higher doses of opioids in patients who need palliative sedation prior to death: Cause or consequence? Eur J Cancer 2011; 47:2341-6. [DOI: 10.1016/j.ejca.2011.06.057] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2011] [Revised: 06/22/2011] [Accepted: 06/27/2011] [Indexed: 11/27/2022]
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9
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Darbari DS, Neely M, van den Anker J, Rana S. Increased clearance of morphine in sickle cell disease: implications for pain management. THE JOURNAL OF PAIN 2011; 12:531-8. [PMID: 21277838 DOI: 10.1016/j.jpain.2010.10.012] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Revised: 09/15/2010] [Accepted: 10/26/2010] [Indexed: 11/13/2022]
Abstract
UNLABELLED Acute vaso-occlusive painful episodes associated with sickle cell disease (SCD) are frequently treated with morphine. Many SCD individuals require relatively higher doses of morphine to achieve optimal analgesia. We studied pharmacokinetics of morphine in SCD to explore if altered disposition could be a factor contributing to increased requirement of morphine in this population. The study subjects were in steady state of health to avoid the effect of hemodynamic changes associated with vaso-occlusion on morphine disposition. The plasma concentrations of morphine and its major metabolites were measured at timed intervals in 21 SCD subjects after they received a single .1 mg/Kg infusion of morphine sulfate. USCPACK software was used to fit candidate pharmacokinetic models. Noncompartmental pharmacokinetic parameters for morphine were calculated. Morphine clearance was 2.4-3.6 L/h, half-life was .3-.7 hours, AUC(0-∞) was 27.7-42.5 ng∗h/mL, and volume of distribution was .96-3.38 L/kg. Clearance of morphine in the study population was 3-10 folds higher than published estimates in the non-SCD population, with correspondingly lower AUC and half-life. Volume of distribution was similar. This observation suggests that due to increased clearance SCD individuals may require higher dose and frequency of morphine to achieve comparable plasma levels. PERSPECTIVE Accelerated clearance of morphine likely related to increased hepatic and renal blood flow may be responsible for increased requirement of morphine in SCD. Although SCD individuals may require higher and more frequent doses of morphine, inter-individual variability of morphine disposition highlights the importance of individualization of the therapy.
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Affiliation(s)
- Deepika S Darbari
- Division of Pediatric Hematology And Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
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10
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Dale O, Thoner J, Nilsen T, Tveita T, Borchgrevink PC, Klepstad P. Serum and cerebrospinal fluid morphine pharmacokinetics after single doses of intravenous and intramuscular morphine after hip replacement surgery. Eur J Clin Pharmacol 2007; 63:837-42. [PMID: 17619868 DOI: 10.1007/s00228-007-0329-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2006] [Accepted: 05/25/2007] [Indexed: 11/30/2022]
Abstract
AIM To compare the time course of morphine and metabolite concentrations in serum and cerebrospinal fluid (CSF) after intravenous and intramuscular administration after surgery. METHODS This was a randomized double-blind, double-dummy study in patients who had undergone hip replacement surgery. Morphine (M, 10 mg) was administered intravenously (IV) or intramuscularly (IM). Arterial blood and CSF samples (from a spinal catheter) were drawn simultaneously at 10, 30, 60, and 120 min after administration. Morphine and metabolites [morphine-3-glucuronide (M-3-G), morphine-6-glucuronide (M-6-G), and normorphine (NM)] were determined by a validated liquid chromatography-tandem mass spectrometry method. RESULTS Thirty-eight patients were included: 13 men and 25 women, 20 in the IV, 18 in the IM group. Serum concentrations of M after 10 min were consistently higher after IM than IV, concentrations of M-3-G and M-6-G after IM surpassed those of IV after 45 min. NM was not found. None of the metabolites was found in CSF. CSF morphine concentrations and CSF/serum concentration ratios were consistently higher after IV compared to IM. The mean AUC(CSF)/AUC(serum) (0-120 min) concentration ratios were 0.18 and 0.09 after IV and IM, respectively. CONCLUSIONS The uptake of morphine to the CSF was consistently higher after IV administration than after IM already after 10 min. The higher CSF concentration may be caused by an initially higher morphine blood/CSF gradient following IV morphine injection. The pharmacokinetic findings are compatible with a more rapid and extensive initial effect of IV morphine compared with IM.
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Affiliation(s)
- O Dale
- Pain and Palliation Research Group, Department of Circulation and Medical Imaging, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway.
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11
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Abstract
The emergence of opioid-induced neurotoxicity has gained increasing recognition in the literature in the past decade. Exciting developments at the receptor and intracellular level have revealed some insights into the potential mechanisms underlying this phenomenon. The hitherto reported clinical benefits of opioid rotation and dose reduction in the treatment of opioid toxicity warrant further clarification in prospective studies, particularly in relation to their relative value.
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Affiliation(s)
- P G Lawlor
- Palliative Care Program, Grey Nuns Community Hospital & Health Centre, Edmonton, AB, Canada.
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12
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Koulousakis A, Kuchta J, Bayarassou A, Sturm V. Intrathecal opioids for intractable pain syndromes. ACTA NEUROCHIRURGICA. SUPPLEMENT 2007; 97:43-8. [PMID: 17691355 DOI: 10.1007/978-3-211-33079-1_5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/06/2022]
Abstract
For more than 20 years intrathecal opioid application with implantable pumps is an option for selected patients with malignant as well as non-malignant pain. In general, most types of pain should be treatable by opioid medication. However, the associated systemic side-effects such as nausea, vomiting, constipation or the risk of suppression of the central nervous system hinder the application of oral or intravenous opioid therapy as a sole, widely applicable treatment. Causes of non-malignant pain that may represent an indication for intrathecal drug-delivery systems include: failed back syndrome, neuropathic pain, axial spinal pain, complex regional pain syndrome, diffuse pain, brachial plexitis, central pain, failed spinal cord stimulation (SCS) therapy, arachnoiditis, poststroke pain, spinal cord injury pain and peripheral neuropathy. Due to the proximity to the receptor sites, the therapeutic effect of intrathecal drug application lasts longer and the rate of systemic side effects is reduced. Before definitive pump implantation, the therapeutic effect of intrathecal opioid therapy is tested with an external pump. If there is no clear and satisfactory effect in this trial application, pump implantation is not indicated. In our patients, with a follow-up exceeding 3 years, the reduction of non-malignant pain (assessed with the Visual Analogue Scale, VAS) was good or excellent (pain decrease >50%) in 71.3% of the patients, fair (VAS 5-6) in 19.8% and poor (VAS 7-10) in 8.9%. After 3 years of continuous treatment, we observed catheter-related technical problems (catheter dislocation, obstruction, kinking, disconnection or rupture) in 17 of 165 patients. Pump malfunctions were very rare (8 of 165 cases) and limited to older pump types. Reversible, specific drug-related side effects of long-term therapy with intrathecal pumps developed in 32 of the 165 patients. In our series, the mean serum/cerebrospinal fluid (CSF) concentration ratio for morphine was 1/3000, which explains the low rate of systemic side effects. Local diffusion difficulties in CSF cause an uneven distribution of morphine in CSF. Therefore the clinical effect is markedly influenced by the position of the catheter tip, a fact that should be kept in mind during catheter implantation. Intrathecal drug application is cost effective and can significantly improve the quality of life in selected patients. An intensive training in this method and awareness of its specific complications is necessary for everyone to participate in the consulting and implanting team. Pumps for chronic intrathecal opioid application should only be implanted in specialized centers.
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Affiliation(s)
- A Koulousakis
- Department of Neurosurgery, Cologne University, Cologne, Germany
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13
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Shipkova M, Wieland E. Glucuronidation in therapeutic drug monitoring. Clin Chim Acta 2005; 358:2-23. [PMID: 15893300 DOI: 10.1016/j.cccn.2005.02.023] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2005] [Revised: 02/21/2005] [Accepted: 02/22/2005] [Indexed: 11/26/2022]
Abstract
BACKGROUND Glucuronidation is a major drug-metabolizing reaction in humans. A pharmacological effect of glucuronide metabolites is frequently neglected and the value of therapeutic drug monitoring has been questioned. However, this may not always be true. METHODS In this review the impact of glucuronidation on therapeutic drug monitoring has been evaluated on the basis of a literature search and experience from the own laboratory. RESULTS The potential role of monitoring glucuronide metabolite concentrations to optimize therapeutic outcome is addressed on the basis of selected examples of drugs which are metabolized to biologically active/reactive glucuronides. Furthermore indirect effects of glucuronide metabolites on parent drug pharmacokinetics are presented. In addition, factors that may modulate the disposition of these metabolites (e.g. genetic polymorphisms, disease processes, age, and drug-drug interactions) are briefly mentioned and their relevance for the clinical situation is critically discussed. CONCLUSION Glucuronide metabolites can have indirect as well as direct pharmacological or toxicological effects. Although convincing evidence to support the introduction of glucuronide monitoring into clinical practice is currently missing, measurement of glucuronide concentrations may be advantageous in specific situations. If the glucuronide metabolite has an indirect effect on the pharmacokinetics of the parent compound, monitoring of the parent drug may be considered. Furthermore pharmacogenetic approaches considering uridine diphosphate (UDP) glucuronosyltransferases polymorphisms may become useful in the future to optimize therapy with drugs subject to glucuronidation.
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Affiliation(s)
- Maria Shipkova
- Department of Clinical Chemistry and Laboratory Medicine, Klinikum Stuttgart, Stuttgart, Germany.
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14
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Skarke C, Geisslinger G, Lötsch J. Is morphine-3-glucuronide of therapeutic relevance? Pain 2005; 116:177-180. [PMID: 15982815 DOI: 10.1016/j.pain.2005.06.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/10/2005] [Indexed: 11/20/2022]
Affiliation(s)
- Carsten Skarke
- Institute of Clinical Pharmacology, Johann Wolfgang Goethe-University, pharmazentrum frankfurt/ZAFES, Theodor Stern-Kai 7, 60590 Frankfurt am Main, Germany
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Anderson SL, Shreve ST. Continuous Subcutaneous Infusion of Opiates at End-of-Life. Ann Pharmacother 2004; 38:1015-23. [PMID: 15122000 DOI: 10.1345/aph.1d395] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE: To review pertinent controlled trials using the continuous subcutaneous infusion of opioids (CSIO) at end-of-life and offer insight to pharmacists and clinicians into the appropriate use of this route of administration. DATA SOURCES: A MEDLINE search for information regarding the subcutaneous administration of opioids in terminally ill patients (1975-December 2002) was conducted using the key words subcutaneous, narcotics, morphine, hydromorphone, fentanyl, pain, hospices, and palliative care. Additional references were located through review of bibliographies of the articles cited. Case reports and postsurgical studies were excluded. Searches were limited to English-language studies using humans. STUDY SELECTION AND DATA EXTRACTION: Experimental and observational studies were evaluated, using prospective trials as the evidence base for conclusions and including pertinent retrospective trials as they relate to the subcutaneous infusion of opioids at end-of-life. DATA SYNTHESIS: CSIO is effective and safe for use in terminal illness. Appropriate situations for consideration of CSIO are when difficulties arise in using the oral route, standard oral opiate therapy has failed adequate trials, the patient has limited intravenous access, adequate supervision of the CSIO is present, and CSIO will not unduly limit the functional activity of the patient. CONCLUSIONS: CSIO has a proven role in the management of pain at end-of-life. CSIO should not be considered the first route for administration of opiates, but does offer distinct advantages in the appropriate setting. CSIO continues to be a choice for end-of-life patients and is gradually becoming a standard practice in palliative medicine.
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Affiliation(s)
- Stacey L Anderson
- Extended Care and Behavioral Health, Pharmacy Service (719), Lebanon Veterans Affairs Medical Center, Lebanon, PA, USA
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Klepstad P, Borchgrevink PC, Dale O, Zahlsen K, Aamo T, Fayers P, Fougner B, Kaasa S. Routine drug monitoring of serum concentrations of morphine, morphine-3-glucuronide and morphine-6-glucuronide do not predict clinical observations in cancer patients. Palliat Med 2003; 17:679-87. [PMID: 14694919 DOI: 10.1191/0269216303pm835oa] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The clinical importance of routine drug monitoring of serum concentrations of morphine, morphine-6-glucuronide (M6G) and morphine-3-glucuronide (M3G) during chronic morphine therapy is not established. We measured morphine, M6G and M3G serum concentrations in cancer pain patients receiving oral (n = 263, median dose 80 mg/24 hours) or subcutaneous (sc) (n = 35, median dose 110 mg/24 hours) morphine. Regression analyses were performed to investigate if serum concentrations of morphine, M3G and M6G predicted pain intensity (Brief Pain Inventory), health-related quality-of-life variables (EORTC QLQ-C30) and cognitive function (Mini-Mental Score). Serum concentrations were also compared in patients categorized as morphine 'treatment successes' and 'treatment failures'. We observed that serum concentrations of morphine, M6G or M3G did not predict pain intensity, cognitive function, nausea or tiredness. 'Treatment failures' caused by nausea, tiredness, cognitive failure or constipation did not have statistically significant different morphine, M6G and M3G serum concentrations than patients classified as 'treatment successes'. In conclusion, this study did not observe any concentration-effect relationships of morphine, M3G or M6G with pain intensity, nausea, constipation, tiredness or cognitive failure in blood samples obtained during routine clinical drug monitoring in cancer patients. This result suggests that therapeutic drug monitoring as a routine tool during chronic morphine treatment has limited value for clinical decision making.
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Affiliation(s)
- Pål Klepstad
- Department of Anaesthesia and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
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17
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Takahashi M, Ohara T, Yamanaka H, Shimada A, Nakaho T, Makoto Y. The oral-to-intravenous equianalgesic ratio of morphine based on plasma concentrations of morphine and metabolites in advanced cancer patients receiving chronic morphine treatment. Palliat Med 2003; 17:673-8. [PMID: 14694918 DOI: 10.1191/0269216303pm824oa] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
To provide additional pharmacokinetic evidence for the oral-to-parenteral relative potency ratio of 1:2 to 1:3 for chronic morphine use in a palliative care setting, we determined the plasma concentrations of morphine and its major metabolites, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G), in hospitalized advanced cancer patients maintained on long-term oral or intravenous morphine. There were significant linear correlations between daily doses of morphine and plasma concentrations (molar base) of morphine, M3G and M6G for both routes of administration. The oral-to-intravenous relative ratios of the regression coefficients were 2.9 for morphine and 1.8 for morphine + M6G. The morphine kinetic variables were not significantly influenced by any hepato-renal biochemical markers. These results support the commonly used oral-to-intravenous relative potency ratio of 1:2 to 1:3 in patients with cancer pain receiving chronic morphine treatment.
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Affiliation(s)
- Masahiko Takahashi
- Division of Pain Control, Department of Anesthesiology and Emergency Medicine, Tohoku University Postgraduate Medical School, 1-1 Seiryo, Aoba-ku, Sendai 980-8574, Japan.
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18
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Hemstapat K, Monteith GR, Smith D, Smith MT. Morphine-3-glucuronide's neuro-excitatory effects are mediated via indirect activation of N-methyl-D-aspartic acid receptors: mechanistic studies in embryonic cultured hippocampal neurones. Anesth Analg 2003; 97:494-505. [PMID: 12873944 DOI: 10.1213/01.ane.0000059225.40049.99] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
UNLABELLED Indirect evidence indicates that morphine-3-glucuronide (M3G) may contribute significantly to the neuro-excitatory side effects (myoclonus and allodynia) of large-dose systemic morphine. To gain insight into the mechanism underlying M3G's excitatory behaviors, we used fluo-3 fluorescence digital imaging techniques to assess the acute effects of M3G (5-500 microM) on the cytosolic calcium concentration ([Ca(2+)](CYT)) in cultured embryonic hippocampal neurones. Acute (3 min) exposure of neurones to M3G evoked [Ca(2+)](CYT) transients that were typically either (a) transient oscillatory responses characterized by a rapid increase in [Ca(2+)](CYT) oscillation amplitude that was sustained for at least approximately 30 s or (b) a sustained increase in [Ca(2+)](CYT) that slowly recovered to baseline. Naloxone-pretreatment decreased the proportion of M3G-responsive neurones by 10%-25%, implicating a predominantly non-opioidergic mechanism. Although the naloxone-insensitive M3G-induced increases in [Ca(2+)](CYT) were completely blocked by N-methyl-D-aspartic acid (NMDA) antagonists and 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) (alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid/kainate antagonist), CNQX did not block the large increase in [Ca(2+)](CYT) evoked by NMDA (as expected), confirming that M3G indirectly activates the NMDA receptor. Additionally, tetrodotoxin (Na(+) channel blocker), baclofen (gamma-aminobutyric acid(B) agonist), MVIIC (P/Q-type calcium channel blocker), and nifedipine (L-type calcium channel blocker) all abolished M3G-induced increases in [Ca(2+)](CYT), suggesting that M3G may produce its neuro-excitatory effects by modulating neurotransmitter release. However, additional characterization is required. IMPLICATIONS Large systemic doses of morphine administered to some patients for cancer pain management have been reported to produce myoclonus and allodynia. Indirect evidence implicates the major morphine metabolite, morphine-3-glucuronide (M3G), in these neuro-excitatory side effects. Hence, this study was designed to gain insight into the cellular mechanism responsible for M3G's neuro-excitatory actions.
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Affiliation(s)
- Kamondanai Hemstapat
- School of Pharmacy, The University of Queensland, St Lucia Campus, Brisbane, Australia
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19
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Klepstad P, Dale O, Kaasa S, Zahlsen K, Aamo T, Fayers P, Borchgrevink PC. Influences on serum concentrations of morphine, M6G and M3G during routine clinical drug monitoring: a prospective survey in 300 adult cancer patients. Acta Anaesthesiol Scand 2003; 47:725-31. [PMID: 12803591 DOI: 10.1034/j.1399-6576.2003.00138.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND In order to make treatment decisions physicians should have knowledge about the relations between patient characteristics and drug disposition. Dose, route of administration, gender, age and renal function are reported to influence the serum concentrations of morphine, morphine-6-glucurnide (M6G) and morphine-3-glucuronide (M3G) during chronic treatment of cancer pain. These factors, however, are not evaluated in studies with a sample size sufficient to explore predictive factors. METHODS Three hundred consecutive morphine users admitted because of a malignant disease were recruited. The relations of serum concentrations of morphine, M6G and M3G to patient characteristics (gender, age, weight, renal function, liver function, dose, route of administration) were explored, and regression analysis performed to investigate whether these characteristics predicted serum concentrations obtained during routine clinical drug monitoring. RESULTS Morphine dose was associated with serum concentrations of morphine (r = 0.69), M6G (r = 0.76) and M3G (r = 0.76). Oral morphine resulted in higher dose-adjusted M6G and M3G serum concentrations compared with s.c. morphine. Creatinine serum concentrations correlated with serum concentrations of M6G and M3G. Dose and route of administration predicted morphine serum concentrations, while dose and renal function predicted M6G and M3G serum concentrations. Age was an additional factor predicting M3G concentrations. Dose was the only factor that explained a clinically significant part of the observed variability. CONCLUSION Patient characteristics predict only minor parts of the variability of morphine, M3G and M6G serum concentrations observed during routine clinical drug-monitoring in cancer patients.
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Affiliation(s)
- P Klepstad
- Department of Anesthesia and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
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20
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Andersen G, Christrup L, Sjøgren P. Relationships among morphine metabolism, pain and side effects during long-term treatment: an update. J Pain Symptom Manage 2003; 25:74-91. [PMID: 12565191 DOI: 10.1016/s0885-3924(02)00531-6] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The two metabolites of morphine, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G), have been studied intensively in animals and humans during the past 30 years in order to elucidate their precise action and possible contribution to the desired effects and side effects seen after morphine administration. M3G and M6G are formed by morphine glucuronidation, mainly in the liver, and are excreted by the kidneys. The metabolites are found in the cerebrospinal fluid after single as well as multiple doses of morphine. M6G binds to opioid receptors, and animal studies have demonstrated that M6G may be a more potent analgesic than morphine. Results from human studies regarding the analgesic effect of M6G are not unanimous. The potency ratio between systemic M6G and morphine in humans has not been settled, but is probably lower than previously assumed. Hitherto, only a few studies have found evidence for a contributory effect of M6G to the overall effects observed after morphine administration. Several studies have demonstrated that administration of M6G is accompanied by fewer and a milder degree of opioid-like side effects than observed after morphine administration, but most of the studies have used lower doses of M6G than of morphine. M3G displays very low affinity for opioid receptors and has no analgesic activity. Animal studies have shown that M3G may antagonize the analgesic effect of morphine and M6G, but no human studies have demonstrated this. M3G has also been connected to certain neurotoxic symptoms, such as hyperalgesia, allodynia and myoclonus, which have been observed after administration of M3G or high doses of morphine in animals. The symptoms have been reported sporadically in humans treated primarily with high doses of morphine, but the role of M3G in eliciting the symptoms is not fully elucidated.
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Affiliation(s)
- Gertrud Andersen
- Multidisciplinary Pain Center, Herlev University Hospital, Herlev, Denmark
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Meineke I, Freudenthaler S, Hofmann U, Schaeffeler E, Mikus G, Schwab M, Prange HW, Gleiter CH, Brockmöller J. Pharmacokinetic modelling of morphine, morphine-3-glucuronide and morphine-6-glucuronide in plasma and cerebrospinal fluid of neurosurgical patients after short-term infusion of morphine. Br J Clin Pharmacol 2002; 54:592-603. [PMID: 12492606 DOI: 10.1046/j.1365-2125.2002.t01-1-01689.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AIMS Concentrations in the cerebrospinal fluid (CSF) are a useful approximation to the effect site for drugs like morphine. However, CSF samples, are available only in rare circumstances. If they can be obtained they may provide important insights into the pharmacokinetics/pharmacodynamics of opioids. METHODS Nine neurological and neurosurgical patients (age 19-69 years) received 0.5 mg kg-1 morphine sulphate pentahydrate as an intravenous infusion over 30 min. Plasma and CSF were collected for up to 48 h. Concentration time-course and interindividual variability of morphine (M), morphine-3-glucuronide (M3G) and morphine-6 glucuronide (M6G) were analysed using population pharmacokinetic modelling. RESULTS While morphine was rapidly cleared from plasma (total clearance = 1838 ml min-1 (95% CI 1668, 2001 ml min-1)) the glucuronide metabolites were eliminated more slowly (clearance M3G = 44.5 ml min-1 (35.1, 53.9 ml min-1), clearance M6G = 42.1 ml min-1 (36.4, 47.7 ml min-1)) and their clearance could be described as a function of creatinine clearance. The central volumes of distribution were estimated to be 12.7 l (11.1, 14.3 l) for morphine. Transfer from the central compartment into the CSF was also rapid for M and considerably slower for both glucuronide metabolites. Maximum concentrations were achieved after 102 min (M), 417 min (M3G) and 443 min (M6G). A P-glycoprotein exon 26 polymorphism previously found to be linked with transport activity could be involved in CSF accessibility, since the homozygous mutant genotype was associated (P < 0.001) with high maximum CSF concentrations of M but not M3G or M6G. CONCLUSIONS From the population pharmacokinetic model presented, CSF concentration profiles can be derived for M, M3G and M6G on the basis of dosing information and creatinine clearance without collecting CSF samples. Such profiles may then serve as the link between dose regimen and effect measurements in future clinical effect studies.
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Affiliation(s)
- Ingolf Meineke
- Department of Clinical Pharmacology University of Göttingen, Germany.
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Ogutu BR, Newton CRJC, Muchohi SN, Otieno GO, Kokwaro GO. Phenytoin pharmacokinetics and clinical effects in African children following fosphenytoin and chloramphenicol coadministration. Br J Clin Pharmacol 2002; 54:635-42. [PMID: 12492612 PMCID: PMC1874507 DOI: 10.1046/j.1365-2125.2002.01689.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2002] [Accepted: 06/17/2002] [Indexed: 11/20/2022] Open
Abstract
AIMS Some children with malaria and convulsions also have concurrent bacterial meningitis. Chloramphenicol is used to treat the latter whereas phenytoin is used for convulsions. Since chloramphenicol inhibits the metabolism of phenytoin in vivo, we studied the effects of chloramphenicol on phenytoin pharmacokinetics in children with malaria. METHODS Multiple intravenous (i.v.) doses of chloramphenicol succinate (CAP) (25 mg kg-1 6 hourly for 72 h) and a single intramuscular (i.m.) seizure prophylactic dose of fosphenytoin (18 mg kg-1 phenytoin sodium equivalents) were concomitantly administered to 15 African children with malaria. Control children (n = 13) with malaria received a similar dose of fosphenytoin and multiple i.v. doses (25 mg kg-1 8 hourly for 72 h) of cefotaxime (CEF). Blood pressure, heart rate, respiratory rate, oxygen saturation, level of consciousness and convulsion episodes were monitored. Cerebrospinal fluid (CSF) and plasma phenytoin concentrations were determined. RESULTS The area under the plasma unbound phenytoin concentration-time curve (AUC(0, infinity ); means (CAP, CEF): 58.5, 47.6 micro g ml-1 h; 95% CI for difference between means: -35.0, 11.4), the peak unbound phenytoin concentrations (Cmax; medians: 1.12, 1.29 micro g ml-1; 95% CI: -0.5, 0.04), the times to Cmax (tmax; medians: 4.0, 4.0 h; 95% CI: -2.0, 3.7), the CSF:plasma phenytoin ratios (means: 0.21, 0.22; 95% CI: -0.8, 0.10), the fraction of phenytoin unbound (means: 0.06, 0.09; 95% CI: -0.01, 0.07) and the cardiovascular parameters were not significantly different between CAP and CEF groups. However, mean terminal elimination half-life (t1/2,z) was significantly longer (23.7, 15.5 h; 95% CI: 1.71, 14.98) in the CAP group compared with the CEF group. Seventy per cent of the children had no convulsions during the study period. CONCLUSIONS Concomitant administration of chloramphenicol and a single i.m. dose of fosphenytoin alters the t1/2,z but not the other pharmacokinetic parameters or clinical effects of phenytoin in African children with severe malaria. Moreover, a single i.m. dose of fosphenytoin provides anticonvulsant prophylaxis in the majority of the children over 72 h. However, a larger study would be needed to investigate the effect of concomitant administration of multiple doses of the two drugs in this population of patients.
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Affiliation(s)
- Bernhards R Ogutu
- Kenya Medical Research Institute [KEMRI]/Wellcome Trust Centre for Geographic Medicine Research (Coast), Kilifi, Kenya.
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Andersen G, Jensen NH, Christrup L, Hansen SH, Sjøgren P. Pain, sedation and morphine metabolism in cancer patients during long-term treatment with sustained-release morphine. Palliat Med 2002; 16:107-14. [PMID: 11969141 DOI: 10.1191/0269216302pm512oa] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Morphine-6-glucuronide (M-6-G) and morphine-3-glucuronide (M-3-G) are the two most important metabolites of morphine. Both are pharmacologically active, however, with different effects. M-6-G has been demonstrated capable of inducing anti-nociception and sedation, and M-3-G may induce behavioural excitation and possibly antagonise anti-nociception. Their impact on pharmacodynamics in patients in long-term treatment with oral morphine remains to be settled. METHODS Forty-two cancer patients treated with oral sustained-release (SR) morphine were assessed for pain, sedation and other side effects related to morphine treatment. Blood samples were analysed for morphine, M-3-G and M-6-G by high-performance liquid chromatography (HPLC). RESULTS Significant correlations were found between the daily dose of SR morphine and plasma morphine (M) (r = 0.535, P < 0.001), plasma M-6-G (r = 0.868, P < 0.001) and plasma M-3-G (r = 0.865, P < 0.001). There was no relationship between plasma morphine, M-6-G, M-6-G/M and pain and sedation scores. Seventy-nine percent of the patients suffered from dryness of the mouth, which was the most frequent side effect observed. Patients in this group had higher plasma morphine and M-6-G concentrations than patients who did not suffer from this side effect. CONCLUSION The plasma concentrations of morphine and its metabolites, M-3-G and M-6-G, are significantly correlated to the daily dose of SR morphine. Although M-6-G has analgesic properties, no associations were found between pain and plasma morphine and morphine metabolites. This may be due to the multitudinous factors affecting the dose-effect relationship. Patients with dryness of the mouth had higher concentrations of morphine and M-6-G than patients without this side effect.
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Affiliation(s)
- G Andersen
- Multidisciplinary Pain Centre, Herlev University Hospital, Herlev 2730, Copenhagen, Denmark
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Andersen G, Christrup LL, Sjøgren P, Hansen SH, Jensen NH. Changing M3G/M6G ratios and pharmacodynamics in a cancer patient during long-term morphine treatment. J Pain Symptom Manage 2002; 23:161-4. [PMID: 11844638 DOI: 10.1016/s0885-3924(01)00398-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A cancer patient receiving long-term oral sustained-release morphine treatment and periodically presenting with unusually high plasma M3G/M6G ratios is described. We found the patient's formation of M6G more unstable and perhaps delayed compared to the formation of M3G. There is no apparent explanation for this phenomenon and the high M3G/M6G ratios had no implications for the patient's pain experience or side effects from the morphine treatment.
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Affiliation(s)
- Gertrud Andersen
- Multidiciplinary Pain Center, Herlev University Hospital, Herlev, Denmark
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Morita T, Tei Y, Tsunoda J, Inoue S, Chihara S. Increased plasma morphine metabolites in terminally ill cancer patients with delirium: an intra-individual comparison. J Pain Symptom Manage 2002; 23:107-13. [PMID: 11844630 DOI: 10.1016/s0885-3924(01)00392-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Delirium often causes severe distress for terminally ill cancer patients, and treatment of underlying pathologies is important to achieve symptom alleviation. Although accumulation of morphine metabolites may play an important role in development of delirium, empirical findings are conflicting due to a large inter-individual variation in morphine-related concentrations. To explore intra-individual changes of morphine metabolite concentrations before and after occurrence of terminal delirium, a prospective observational study was performed on terminally ill cancer patients. Among 131 consecutive hospice inpatients, 16 samples from 8 patients who received two blood samplings before and after development of delirium were analyzed. Delirium developed a median of 5 days before death, and clinical causes were attributed to multi-organ failure. Plasma concentrations of morphine-6-glucuronide (M-6-G) and morphine-3-glucuronide (M-3-G) significantly increased after development of delirium within the same patient. Mean normalized concentrations of M-6-G and M-3-G elevated from 1.24 +/- 1.06 to 2.94 +/- 3.52 ng/mL/mg (P = 0.016), and from 7.46 +/- 4.75 to 15.4 +/- 13.2 ng/mL/mg (P = 0.016), respectively. Normalized morphine concentration increased with a marginal statistical significance from 0.54 +/- 0.27 to 0.83 +/- 0.22 ng/mL/mg (P = 0.055). In conclusion, plasma concentrations of M-6-G and M-3-G were significantly higher after development of terminal delirium than before. It is suggested that accumulations of morphine metabolites can contribute to development of delirium in cancer patients whose death is impending.
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Affiliation(s)
- Tatsuya Morita
- Seirei Hospice, Seirei Mikatabara Hospital, Shizuoka, Japan
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Abstract
Morphine-6-beta-glucuronide (M6G) is an opioid agonist that plays a role in the clinical effects of morphine. Although M6G probably crosses the blood-brain barrier with difficulty, during long term morphine administration it may reach sufficiently high CNS concentrations to exert clinically relevant opioid effects. As a consequence of its almost exclusive renal elimination, M6G may accumulate in the body of patients with impaired renal function and cause severe opioid adverse effects with insidious onset and long persistence. Its profile of receptor affinities, however, gives reason to speculate that M6G may exhibit analgesic effects while causing fewer adverse effects than morphine. This is supported by reports of the good tolerability of intrathecal and intravenous injections of M6G in humans with intact renal function. M6G may thus be contemplated as an analgesic for short term postoperative analgesia, especially for intrathecal analgesic therapy. In addition, its possibly higher potency than morphine makes M6G a candidate opioid for local or peripheral analgesic therapy. However, current knowledge is too incomplete to finally judge the clinical usefulness of M6G. The next topics for clinical research on M6G should include: (i) a comparison of the potencies of M6G and morphine to cause wanted and unwanted clinical effects; (ii) development of a predictive population pharmacokinetic-pharmacodynamic model of M6G with calculation of the transfer half-life between plasma and effect site; and (iii) identification of cofactors influencing the action of M6G that can serve as predictors for the clinical outcome of morphine/M6G therapy in an individual including the pharmacogenetics of M6G.
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Affiliation(s)
- J Lötsch
- Johann-Wolfgang-Goethe-Universität, Frankfurt am Main, Germany.
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Gurwell JA, Nath A, Sun Q, Zhang J, Martin KM, Chen Y, Hauser KF. Synergistic neurotoxicity of opioids and human immunodeficiency virus-1 Tat protein in striatal neurons in vitro. Neuroscience 2001; 102:555-63. [PMID: 11226693 PMCID: PMC4300203 DOI: 10.1016/s0306-4522(00)00461-9] [Citation(s) in RCA: 134] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Human immunodeficiency virus (HIV) infection selectively targets the striatum, a region rich in opioid receptor-expressing neural cells, resulting in gliosis and neuronal losses. Opioids can be neuroprotective or can promote neurodegeneration. To determine whether opioids modify the response of neurons to human immunodeficiency virus type 1 (HIV-1) Tat protein-induced neurotoxicity, neural cell cultures from mouse striatum were initially characterized for mu and/or kappa opioid receptor immunoreactivity. These cultures were continuously treated with morphine, the opioid antagonist naloxone, and/or HIV-1 Tat (1-72) protein, a non-neurotoxic HIV-1 Tat deletion mutant (TatDelta31-61) protein, or immunoneutralized HIV-1 Tat (1-72) protein. Neuronal and astrocyte viability was examined by ethidium monoazide exclusion, and by apoptotic changes in nuclear heterochromatin using Hoechst 33342. Morphine (10nM, 100nM or 1microM) significantly increased Tat-induced (100 or 200nM) neuronal losses by about two-fold at 24h following exposure. The synergistic effects of morphine and Tat were prevented by naloxone (3microM), indicating the involvement of opioid receptors. Furthermore, morphine was not toxic when combined with mutant Tat or immunoneutralized Tat. Neuronal losses were accompanied by chromatin condensation and pyknosis. Astrocyte viability was unaffected. These findings demonstrate that acute opioid exposure can exacerbate the neurodegenerative effect of HIV-1 Tat protein in striatal neurons, and infer a means by which opioids may hasten the progression of HIV-associated dementia.
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Affiliation(s)
- Julie A. Gurwell
- Department of Anatomy & Neurobiology University of Kentucky College of Medicine Lexington, Kentucky 40536-0298
| | - Avindra Nath
- Department of Neurology University of Kentucky College of Medicine Lexington, Kentucky 40536-0284
- Department of Microbiology & Immunology University of Kentucky College of Medicine Lexington, Kentucky 40536-0298
| | - Qinmiao Sun
- Department of Microbiology & Immunology University of Kentucky College of Medicine Lexington, Kentucky 40536-0298
| | - Jiayou Zhang
- Department of Microbiology & Immunology University of Kentucky College of Medicine Lexington, Kentucky 40536-0298
| | - Kenneth M. Martin
- Department of Anatomy & Neurobiology University of Kentucky College of Medicine Lexington, Kentucky 40536-0298
| | - Yan Chen
- Department of Anatomy & Neurobiology University of Kentucky College of Medicine Lexington, Kentucky 40536-0298
| | - Kurt F. Hauser
- Department of Anatomy & Neurobiology University of Kentucky College of Medicine Lexington, Kentucky 40536-0298
- Markey Cancer Center University of Kentucky Medical Center Lexington, Kentucky 40536-0084
- To whom correspondence should be addressed: Kurt F. Hauser, Ph.D. Department of Anatomy & Neurobiology University of Kentucky College of Medicine 800 Rose Street, Lexington, KY 40536-0298 Phone: (859) 323-6477; FAX: (859) 323-5946
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Brandsson S, Karlsson J, Morberg P, Rydgren B, Eriksson BI, Hedner T. Intraarticular morphine after arthroscopic ACL reconstruction: a double-blind placebo-controlled study of 40 patients. ACTA ORTHOPAEDICA SCANDINAVICA 2000; 71:280-5. [PMID: 10919300 DOI: 10.1080/000164700317411889] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We compared analgesic effects and pharmacokinetics of intraarticular versus intravenous administration of morphine after arthroscopic anterior cruciate ligament surgery. In a double-blind placebo-controlled study, 40 patients were randomly allocated to one of four treatment groups. Group I received 1 mg morphine intraarticularly and saline intravenously; group II received 5 mg morphine intraarticularly and saline intravenously; group III received 5 mg saline intraarticularly and morphine intravenously and group IV, the control group, received saline both intraarticularly and intravenously. The pain scores were significantly lower in groups I and II at 24 hours postoperatively than in group IV, and in group II during the rest of the postoperative period, as compared to groups III and IV. After intraarticular injection of 1 mg and 5 mg morphine, respectively, low concentrations of morphine-6-glucuronide (M6G) were found in the circulation, while morphine-3-glucuronide (M3G) appeared late after the injection in concentrations that considerably exceeded those of morphine in groups I and II. The analgesic effect of intraarticular morphine together with the low levels of morphine and morphine-6-glucuronide in plasma further strengthens the view that opioids have a peripheral mechanism of action.
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Affiliation(s)
- S Brandsson
- Department of Orthopedics, Sahlgrenska University Hospital/Ostra, Göteborg, Sweden.
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Stuart-Harris R, Joel SP, McDonald P, Currow D, Slevin ML. The pharmacokinetics of morphine and morphine glucuronide metabolites after subcutaneous bolus injection and subcutaneous infusion of morphine. Br J Clin Pharmacol 2000; 49:207-14. [PMID: 10718775 PMCID: PMC2014910 DOI: 10.1046/j.1365-2125.2000.00141.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AIMS To investigate the pharmacokinetics of morphine, morphine-6-glucuronide (M6G) and morphine-3-glucuronide (M3G) in healthy volunteers after the administration of morphine by subcutaneous bolus injection (s.c.b.) and subcutaneous infusion (s.c. i.) over 4 h, and to compare the results with the intravenous bolus (i.v.) administration of morphine. METHODS Six healthy volunteers each received 5 mg morphine sulphate by i.v., s.c.b. and short s.c.i. over 4 h, on three separate occasions, in random order, each separated by at least 1 week. Plasma samples were assayed for morphine, M6G and M3G. RESULTS After i.v. morphine, the concentrations of morphine, M6G and M3G and their pharmacokinetic parameters were similar to those we have observed previously, in other healthy volunteers (when standardized to nmol l- 1, for a 10 mg dose to a 70 kg subject). After s.c.b. morphine, similar results were obtained except that the median tmax values for morphine and M3G were significantly longer than after i.v. morphine (P< 0.001 and P< 0.05, respectively), with a trend to a longer tmax for M6G (P = 0. 09). The appearance half-lives after s.c.b. morphine for M6G and M3G were also significantly longer than after i.v. morphine (P = 0.03 and P< 0.05, respectively). Comparison of log-transformed AUC values indicated that i.v. and s.c.b. administration of morphine were bioequivalent with respect to morphine, M6G and M3G. In comparison with i.v. morphine, morphine by s.c.i. was associated with significantly longer median tmax values for morphine (P< 0.001), M6G (P< 0.001) and M3G (P< 0.05), and the mean standardized Cmax values significantly lower than after both i.v. and s.c.b. morphine (morphine P< 0.001, M6G P< 0.001 and M3G P< 0.01 for each comparison). Comparison of log-transformed AUC values after i.v. and s.c.i. morphine indicated that the two routes were not bioequivalent for morphine (log-transformed AUC ratio 0.78, 90% CI 0.66-0.93), M6G (0.72, 90% CI 0.63-0.82), or M3G (0.65, 90% CI 0.54-0.78). A small stability study indicated no evidence of adsorptive losses from morphine infused over 4 h using the infusion devices from the study. CONCLUSIONS Although bioequivalence was demonstrated between the s. c.b. and i.v. routes of morphine administration, the bioavailabilities of morphine, M6G and M3G after s.c.i. were significantly lower than after i.v. administration. However, despite this, the study demonstrates that the subcutaneous route is an effective method for the parenteral administration of morphine.
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Affiliation(s)
- R Stuart-Harris
- Department of Medical Oncology and Palliative Care, Westmead Hospital, Westmead, NSW 2145, Australia.
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Abstract
The liver is the major site of biotransformation for most opioids. Thus, the disposition of these drugs may be affected in patients with liver insufficiency. The major metabolic pathway for most opioids is oxidation. The exceptions are morphine and buprenorphine, which primarily undergo glucuronidation, and remifentanil, which is cleared by ester hydrolysis. Oxidation of opioids is reduced in patients with hepatic cirrhosis, resulting in decreased drug clearance [for pethidine (meperidine), dextropropoxyphene, pentazocine, tramadol and alfentanil] and/or increased oral bioavailability caused by a reduced first-pass metabolism (for pethidine, dextropropoxyphene, pentazocine and dihydrocodeine). Although glucuronidation is thought to be less affected in liver cirrhosis, and clearance of morphine was found to be decreased and oral bioavailability increased. The consequence of reduced drug metabolism is the risk of accumulation in the body, especially with repeated administration. Lower doses or longer administration intervals should be used to remedy this risk. Special risks are known for pethidine, with the potential for the accumulation of norpethidine, a metabolite that can cause seizures, and for dextropropoxyphene, for which several cases of hepatotoxicity have been reported. On the other hand, the analgesic activity of codeine and tilidine depends on transformation into the active metabolites, morphine and nortilidine, respectively. If metabolism is decreased in patients with chronic liver disease, the analgesic action of these drugs may be compromised. Finally, the disposition of a few opioids, such as fentanyl, sufentanil and remifentanil, appears to be unaffected in liver disease.
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Affiliation(s)
- I Tegeder
- Center of Pharmacology, Johann Wolfgang Goethe-University of Frankfurt, Frankfurt am Main, Germany
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Dennis GC, Soni D, Dehkordi O, Millis RM, James H, West WL, Taylor RE. Analgesic responses to intrathecal morphine in relation to CSF concentrations of morphine-3,beta-glucuronide and morphine-6,beta-glucuronide. Life Sci 1999; 64:1725-31. [PMID: 10353626 DOI: 10.1016/s0024-3205(99)00110-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
This study was performed to determine whether variations in analgesic responses to intrathecal morphine could be explained by cerebrospinal fluid (CSF) concentrations of morphine metabolites. Twenty-four CSF samples were collected at the beginning, middle and end of treatment periods in seven cancer patients with pain of malignant origin. CSF concentrations of morphine-3,beta-glucuronide (M3G) and morphine-6,beta-glucuronide (M6G) metabolites were measured by gas chromatography/mass spectrometry. Analgesic responses to morphine were estimated concurrent with CSF collection using a visual analog scale representing percentages of pain relief. Effective analgesia was defined as > or = 75% pain relief. CSF concentration of M3G and M6G in the 24 samples were 722 +/- 116 ng/ml and 699 +/- 158 ng/ml, respectively. CSF samples were categorized into two groups: (1) those collected during effective analgesia (N=14), and (2) those collected during ineffective analgesia (N=10). M6G levels detected in group 1 samples (effective analgesia) were significantly greater than those found in group 2 samples (ineffective analgesia) (978 +/- 243 ng/ml vs 309 +/- 68 ng/ml, P<0.05). Intergroup differences in CSF M3G concentrations and M3G/M6G ratios were not significant. It is concluded that CSF M6G may be indicative of effectiveness of analgesia in cancer patients subjected to intrathecal morphine.
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Affiliation(s)
- G C Dennis
- Department of Surgery, Howard University Hospital, Washington, DC 20060, USA
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Abstract
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 morphine metabolites, morphine-3-glucuronide and morphine-6-glucuronide, in both normal and pathological states have been reviewed in the current literature. Therapeutic implications are also reviewed on the basis of experimental and clinical reports. The presence of these metabolites should be recognized in the chronic treatment of cancer pain with morphine, especially in the presence of renal impairment, and should be considered to have an important influence on opioid responsiveness, defined as a balance between the achievement of an optimal analgesia and the occurrence of adverse effects.
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Sueoka E, Sueoka N, Kai Y, Okabe S, Suganuma M, Kanematsu K, Yamamoto T, Fujiki H. Anticancer activity of morphine and its synthetic derivative, KT-90, mediated through apoptosis and inhibition of NF-kappaB activation. Biochem Biophys Res Commun 1998; 252:566-70. [PMID: 9837747 DOI: 10.1006/bbrc.1998.9695] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We recently reported that morphine inhibits growth of various human cancer cell lines (IC50/2.7-8.8 mM). We then extended the study using newly synthesized morphine derivatives, such as KT-90 and KT-87, which are analgesics 5 times more potent than morphine. KT-90 was found to inhibit growth of human cancer cell lines (IC50/42-70 microM) up to 80 times more potently than morphine. As for mechanisms of action, KT-90 and morphine induced apoptosis, and inhibited tumor necrosis factor alpha (TNF-alpha) gene expression induced by tumor promoters, okadaic acid and 12-O-tetradecanoylphorbol-13-acetate, associated with reduction of NF-kappaB DNA binding activity. This paper provides evidence that KT compounds confirmed the presence of anticancer activity of morphine in addition to its analgesic action.
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Affiliation(s)
- E Sueoka
- Saitama Cancer Center Research Institute, Ina, Kitaadachi-gun, Saitama, 362-0806, Japan
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Lynn A, Nespeca MK, Bratton SL, Strauss SG, Shen DD. Clearance of Morphine in Postoperative Infants During Intravenous Infusion. Anesth Analg 1998. [DOI: 10.1213/00000539-199805000-00008] [Citation(s) in RCA: 125] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Lynn A, Nespeca MK, Bratton SL, Strauss SG, Shen DD. Clearance of morphine in postoperative infants during intravenous infusion: the influence of age and surgery. Anesth Analg 1998; 86:958-63. [PMID: 9585276 DOI: 10.1097/00000539-199805000-00008] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
UNLABELLED We analyzed morphine clearance values in infants receiving the drug by continuous i.v. infusion for analgesia after surgery, because we found lower steady-state morphine concentrations than we expected from our previous studies. Infants received morphine after a loading dose of 0.05 mg/kg and continuous infusion calculated to reach a steady-state concentration of 20 ng/mL. Blood was sampled twice on Postoperative Day 1 at times separated by at least 2 h, and morphine and morphine-6-glucuronide (M-6-G) concentrations were determined by high-performance liquid chromatography. Clearance of morphine was calculated as infusion rate divided by the steady-state morphine concentration. Morphine given to 26 infants by continuous i.v. infusion after major noncardiac surgery has rapidly increasing clearance values, from a median value of 9.2 mL x min(-1) x kg(-1) in infants 1-7 days old, 25.3 in infants 31-90 days old, and 31.0 in infants 91-180 days old to 48.9 in infants 180-380 days old. Adult clearance values are reached by 1 mo of age, more quickly than in infants of the same age previously studied who received morphine after cardiac surgeries. M-6-G was measured in all infants. The ratio of M-6-G to morphine concentrations was 1.9-2.1 in these infants, which is lower than ratios reported in older infants or adults by others, but higher than those reported in newborns. Infants with normal cardiovascular systems undergoing surgery clear morphine more efficiently than infants of the same age undergoing cardiac surgery. IMPLICATIONS Morphine removal from the body is slow in newborns but increases to reach adult values in the first months of life. Calculating the clearance of morphine from blood samples drawn during continuous i.v. infusions after surgery shows that this maturation occurs more quickly in infants undergoing noncardiac surgery (by 1-3 mo of age) than in those receiving morphine after cardiac surgery (by 6-12 mo of age).
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Affiliation(s)
- A Lynn
- Department of Anesthesiology, University of Washington School of Medicine, Children's Hospital and Medical Center, Seattle 98105, USA
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