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CPT: Pharmacometrics & Systems... Jan 2022Intravenous (i.v.) morphine is a safe, robust, and recommended treatment for severe pain using the titration principle. Despite its high efficacy, it is impacted by...
Intravenous (i.v.) morphine is a safe, robust, and recommended treatment for severe pain using the titration principle. Despite its high efficacy, it is impacted by organizational constraints related to venous access. Nebulized (NEB) morphine may represent an alternative for titration but pharmacokinetic (PK) properties of short nebulization using routine devices need evaluation. Twenty-seven healthy volunteers were included to receive NEB or i.v. morphine administration using increasing amounts according to Dixon's reference method. Plasma morphine, morphine-3-glucuronide (M3G), and morphine-6-glucuronide (M6G) were quantified. PK modeling and simulations were performed using Monolix. Dixon's method exhibited a significantly higher morphine dose regimen in the NEB group versus the i.v. group (6.2 [5.3-7.1] vs. 3.0 [2.0-4.0] mg, p < 0.001). Morphine, M3G, and M6G dose-normalized exposure were significantly lower in the NEB group versus the i.v. group: morphine (19 [13-23] vs. 1044 [702-1266] µg min/L, p < 0.001), M3G (245 [162-287] vs. 3752 [2487-5165] µg min/L, p < 0.001) and M6G (28 [21-43] vs. 466 [370-723] µg min/L, p < 0.001). The model that best fitted the data consisted in a transit compartment for morphine absorption, three compartments for morphine distribution followed by multiple transit compartments (8.2 and 57.5-min transit time for M3G and M6G, respectively) and a first order elimination for M3G and M6G. Morphine bioavailability in the NEB group was 3.5% using the i.v. group as reference. Administration route and sex significantly influenced morphine and metabolite PKs. This work aimed to evaluate the PKs of NEB morphine compared with the i.v. route. Despite a bioavailability to improve, NEB morphine administration using a routine device is suitable to plan morphine titration.
Topics: Administration, Inhalation; Adult; Analgesics, Opioid; Computer Simulation; Dose-Response Relationship, Drug; Female; Healthy Volunteers; Humans; Injections, Intravenous; Male; Middle Aged; Models, Biological; Morphine; Morphine Derivatives; Nebulizers and Vaporizers; Sex Factors
PubMed: 34842366
DOI: 10.1002/psp4.12735 -
British Journal of Clinical Pharmacology Jun 19961. The pharmacokinetics of morphine, morphine-6-glucuronide (M6G) and morphine-3-glucuronide (M3G) were studied in 19 ventilated newborn infants (24-41 weeks gestation)... (Clinical Trial)
Clinical Trial Randomized Controlled Trial
1. The pharmacokinetics of morphine, morphine-6-glucuronide (M6G) and morphine-3-glucuronide (M3G) were studied in 19 ventilated newborn infants (24-41 weeks gestation) who were given a loading dose of 50 micrograms kg-1 or 200 micrograms kg-1 of diamorphine followed by an intravenous infusion of 15 micrograms kg-1 h-1 of diamorphine. Plasma concentrations of morphine, M3G and M6G were measured during the accrual to steady-state and at steady state of the diamorphine infusion. 2. Following both the 50 micrograms kg-1 or 200 micrograms kg-1 loading doses the mean steady-state plasma concentration (+/- s.d.) of morphine, M3G and M6G were 86 +/- 52 ng ml-1, 703 +/- 400 ng ml-1 and 48 +/- 28 ng ml-1 respectively and morphine clearance was found to be 4.6 +/- 3.2 ml min-1 kg-1. 3. M3G formation clearance was estimated to be 2.5 +/- 1.8 ml min-1 kg-1, and the formation clearance of M6G was estimated to be 0.46 +/- 0.32 ml min-1 kg-1. 4. M3G metabolite clearance was 0.46 +/- 0.60 ml min-1 kg-1, the elimination half-life was 11.1 +/- 11.3 h and the volume of distribution was 0.55 +/- 1.13 l kg-1. M6G metabolite clearance was 0.71 +/- 0.36 ml min-1 kg-1, the elimination half-life was 18.2 +/- 13.6 h and the volume of distribution was 1.03 +/- 0.88 l kg-1. 5. No significant effect of the loading dose (50 micrograms kg-1 or 200 micrograms kg-1) on the plasma morphine or metabolite concentrations or their derived pharmacokinetic parameters was found. 6. We were unable to identify correlations between gestational age of the infants and any of the determined pharmacokinetic parameters. 7. M3G: morphine and M6G: morphine steady-state plasma concentration ratios were 11.0 +/- 10.8 and 0.8 +/- 0.8, respectively. 8. The metabolism of morphine in neonates, in terms of the respective contributions of each glucuronide pathway, was similar to that in adults.
Topics: Analgesics, Opioid; Half-Life; Heroin; Humans; Infant, Newborn; Infant, Premature; Infusions, Intravenous; Morphine; Morphine Derivatives
PubMed: 8799518
DOI: 10.1046/j.1365-2125.1996.03539.x -
Journal of Trace Elements in Medicine... Jul 2020Addiction is a pressing social problem worldwide and opioid dependence can be considered the strongest and most difficult addiction to treat. Mesolimbic and mesocortical... (Review)
Review
Addiction is a pressing social problem worldwide and opioid dependence can be considered the strongest and most difficult addiction to treat. Mesolimbic and mesocortical dopaminergic pathways play an important role in modulation of cognitive processes and decision making and, therefore, changes in dopamine metabolism are considered the central basis for the development of dependence. Disturbances caused by excesses or deficiency of certain elements have a significant impact on the functioning of the central nervous system (CNS) both in physiological conditions and in pathology and can affect the cerebral reward system and therefore, may modulate processes associated with the development of addiction. In this paper we review the mechanisms of interactions between morphine and zinc, manganese, chromium, cadmium, lead, fluoride, their impact on neural pathways associated with addiction, and on antinociception and morphine tolerance and dependence.
Topics: Animals; Humans; Morphine; Morphine Dependence; Neural Pathways; Transition Elements
PubMed: 32179426
DOI: 10.1016/j.jtemb.2020.126495 -
Physiology & Behavior Apr 2018Preclinical studies report that the effective dose for morphine is approximately 2-fold higher in females than males. Following systemic administration, morphine is...
Preclinical studies report that the effective dose for morphine is approximately 2-fold higher in females than males. Following systemic administration, morphine is metabolized via Phase II glucuronidation in the liver and brain into two active metabolites: morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G), each possessing distinct pharmacological profiles. M6G binds to μ opioid receptors and acts as a potent analgesic. In contrast, M3G binds to toll-like receptor 4 (TLR4), initiating a neuroinflammatory response that directly opposes the analgesic effects of morphine and M6G. M3G serum concentrations are 2-fold higher in females than males, however, sex-specific effects of morphine metabolites on analgesia and glial activation in vivo remain unknown. The present studies test the hypothesis that increased M3G, and subsequent TLR4-mediated activation of glia, is a primary mechanism driving the attenuated response to morphine in females. We demonstrate that intra-PAG M6G results in a greater analgesic response in females than morphine alone. M6G analgesia was reversed with co-administration of (-)-naloxone, but not (+)-naloxone, suggesting that this effect is μ opioid receptor mediated. In contrast, intra-PAG administration of M3G significantly attenuated the analgesic effects of systemic morphine in males only, increasing the 50% effective dose of morphine two-fold (5.0 vs 10.3mg/kg) and eliminating the previously observed sex difference. An increase in IL-1β, IL-6 and TNF was observed in females following intra-PAG morphine or M6G. In males, only IL-1β levels increased following morphine. Changes in cytokine levels following M3G were limited to TNF in females. Together, these data implicate sex differences in morphine metabolism, specifically M3G, as a contributing factor in the attenuated response to morphine observed in females.
Topics: Analgesics, Opioid; Animals; Cytokines; Dose-Response Relationship, Drug; Female; Male; Morphine; Morphine Derivatives; Naloxone; Narcotic Antagonists; Nociception; Pain Threshold; Periaqueductal Gray; RNA, Messenger; Rats; Rats, Sprague-Dawley; Sex Characteristics; Time Factors; Toll-Like Receptor 4
PubMed: 29199028
DOI: 10.1016/j.physbeh.2017.11.030 -
Minerva Anestesiologica 2005Managing pain effectively is one of the biggest challenges in medicine, let alone when dealing with the dying patient and his family. For palliative care specialists... (Review)
Review
Managing pain effectively is one of the biggest challenges in medicine, let alone when dealing with the dying patient and his family. For palliative care specialists this is a daily challenge. However, ''To cure when possible, to give comfort always'' is an empty credo if physicians don't use every weapon in the medical arsenal to relieve the suffering caused by chronic pain. It's of course the opioids: morphine, heroin, their synthetic derivatives and other narcotics, a class of medications that conjure up visions of drug addiction and narcotic squads. To say that opioids are stigmatised by such allusions is putting it mildly. An unhealthy proportion of doctors and patients alike are afraid to have anything to do with them, even in when facing their final stages of life. This is particularly so in the Mediterranean society. It is here in Italy that an effort must be made to educate both physicians and the general public, an arduous task to change a long standing belief which requires a quick cultural turn around. Those who refuse opioids because they are afraid of addiction, and the doctors who refuse to prescribe them out of fear or pure unwillingness to address an apprehensive attitude on behalf of his patient, need to be better informed. Most misconceptions about opioids have to do with terminology, because words like ''morphine, addiction, dependency'' and ''tolerance'' mean entirely different things in popular and medical parlance. Add to this the perceptions and attitudes the patient can have with this terminology which then can have a profound effect on the success or failure of a pain control programme. In fact, most people think that medication such as morphine are only for people who are dying and as a consequence is synonymous with death itself. Is this why Italian physicians are not prescribing morphine even though great efforts have been made recently by the Health Ministry to facilitate prescribing laws and costs? It is worthy of serious consideration. Another important issue faced daily by palliative care physicians is the broad number of chronic conditions which could make use of opioids. Severe cancer pain is the most obvious example of an appropriate use of opioids, but hardly the only one. The North American Chronic Pain Association of Canada (NACPAC) advocates the use of opioids for a wide range of conditions causing severe chronic pain, including lower back pain, inflammatory bowel disease, migraines, AIDS, multiple sclerosis and arthritis. Concerns regarding under treatment of chronic pain have captured the attention of patient advocacy groups, policy makers and scientific organisations. Misconceptions of opioid laws, negative social stigma and lack of valid prescribing alternatives to overcome this, together with paucity of formal provider education confound the issue. Much education needs to be done before opioids will be seen as a safe and reasonable treatment for chronic pain here in Italy.
Topics: Analgesics, Opioid; Chronic Disease; Drug Utilization; Europe; Humans; Morphine; Pain, Intractable; Palliative Care; Physicians, Family
PubMed: 16012417
DOI: No ID Found -
Journal of Analytical Toxicology Mar 2021Analysis of postmortem samples with the presence of morphine can sometimes be challenging to interpret. Tolerance complicates interpretation of intoxications and causes...
Analysis of postmortem samples with the presence of morphine can sometimes be challenging to interpret. Tolerance complicates interpretation of intoxications and causes of death due to overlap in therapeutic and fatal concentrations. Determination of metabolites and metabolic ratios can potentially differentiate between abstinence, continuous administration, and perhaps time of administration. The purpose of this study was to (a) develop and validate a method for quantitation of morphine-3β-D-glucuronide, morphine-6β-D-glucuronide, normorphine, codeine-6β-D-glucuronide, norcodeine, codeine, 6-acetylmorphine, and ethylmorphine in urine using liquid chromatography-tandem mass spectrometry; (b) apply the method to opiate related deaths; (c) compare metabolic ratios in urine in different causes of death (CoD) and after different drug intakes and (d) compare heroin intoxications in rapid and delayed deaths. Validation parameters such as precision, bias, matrix effects, stability, process efficiency, and dilution integrity were assessed and deemed acceptable. Lower limits of quantitation ranged from 0.01-0.2 μg/mL for all analytes. Autopsy cases (n=135) with paired blood and urine samples were analyzed. Cases were divided into three groups based on CoD; opiate intoxication, intoxication with other drugs than opiates, and other CoD. The cases were classified by intake: codeine (n=42), heroin (n=36), morphine (n=49), and ethylmorphine (n=3). Five cases were classified as mixed intakes and excluded. Heroin intoxications (n=35) were divided into rapid (n=15) or delayed (n=20) deaths. Parent drug groups were compared using metabolic ratio morphine-3β-D-glucuronide/morphine and significant differences were observed between codeine vs morphine (p=0.005) and codeine vs heroin (p≤0.0001). Urine and blood concentrations, and metabolic ratios in rapid and delayed heroin intoxications were compared and determined a significant difference for morphine (p=0.001), codeine (p=0.009), 6-acetylmorphine (p=0.02) in urine, and morphine (p=0.02) in blood, but there was no significant difference (p=0.9) between metabolic ratios. Morphine-3β-D-glucuronide results suggested a period of abstinence prior to death in 25% of the heroin intoxications.
Topics: Analgesics, Opioid; Chromatography, Liquid; Codeine; Heroin; Morphine; Morphine Derivatives; Substance Abuse Detection; Tandem Mass Spectrometry
PubMed: 33031535
DOI: 10.1093/jat/bkaa157 -
BMJ (Clinical Research Ed.) Feb 1993
Topics: Humans; Morphine; Nociceptors; Pain
PubMed: 8448453
DOI: 10.1136/bmj.306.6876.473 -
European Journal of Pharmaceutical... Apr 2022The inclusion complex formation of morphine and its 18 opioid derivatives with β-cyclodextrin has been studied using nuclear magnetic resonance spectroscopy. Initially,...
The inclusion complex formation of morphine and its 18 opioid derivatives with β-cyclodextrin has been studied using nuclear magnetic resonance spectroscopy. Initially, the protonation equilibria and the acid-base properties of dibasic opioid compounds have been fully characterized. Apparent protonation constants and the relative concentration of the microspecies in cyclodextrin excess were also determined. The 1:1 complex stoichiometry was confirmed by the continuous variation method of Job using UV-VIS spectroscopy. The stability constants of the different protonation forms were determined by H NMR titrations. The highest stability was observed in highly alkaline solutions where the amino group is in its unprotonated, neutral state. The structures of the complexes were investigated by two-dimensional ROESY experiments. Based on the stability constants and ROESY experiments, morphine derivatives with longer side chain on the nitrogen atom such as nalbuphine and naltrexone show stronger complexation. The protonation state of the phenolate group, positioned outside the CD cavity, has only a slight influence on the complex stability.
Topics: Analgesics, Opioid; Cyclodextrins; Magnetic Resonance Spectroscopy; Molecular Structure; Morphine; beta-Cyclodextrins
PubMed: 34999212
DOI: 10.1016/j.ejps.2022.106120 -
Pain Physician Mar 2008For thousands of years, opioids have been used to treat pain, and they continue to be one of the most commonly prescribed medications for pain. It is estimated that 90%... (Review)
Review
For thousands of years, opioids have been used to treat pain, and they continue to be one of the most commonly prescribed medications for pain. It is estimated that 90% of patients presenting to pain centers and receiving treatment in such facilities are on opioids. Opioids can be considered broad-spectrum analgesics that act at multiple points along the pain pathway. Unfortunately, opioids also have the potential for great harm, with multiple side effects and potential complications, some of which are lethal. They are also uniquely addictive, which can lead to misuse and diversion. We reviewed the relevant English literature and did thorough manual searches of the bibliographies of known primary and review articles. We utilized pain relief as the primary outcome measure. Other outcome measures were functional improvement, improvement of psychological status, improvement in work status, and evidence of addiction. Short-term use and improvement was defined as less than 6 months and long-term relief was defined as 6 months or longer. The 3 systematic reviews evaluating long-term effectiveness of opioids for chronic non-cancer pain provided unclear and weak evidence. The results of this review showed that many patients in the included studies were dissatisfied with adverse events or insufficient pain relief from opioids and withdrew from the studies. For patients able to continue on opioids, evidence was weak suggesting that their pain scores were lower than before therapy and that this relief could be maintained long-term (> 6 months). There was also weak evidence that long-term opioid therapy with morphine and transdermal fentanyl not only decreases pain but also improves functioning. Limited evidence was available for the most commonly used opioids, oxycodone and hydrocodone. Evidence for the ability to drive on chronic opioid therapy was moderate without major side effects or complications. It is concluded that, for long-term opioid therapy of 6 months or longer in managing chronic non-cancer pain, with improvement in function and reduction in pain, there is weak evidence for morphine and transdermal fentanyl. However, there is limited or lack of evidence for all other controlled substances, including the most commonly used drugs, oxycodone and hydrocodone.
Topics: Analgesics, Opioid; Drug Administration Schedule; Fentanyl; Humans; Methadone; Morphine; Oxycodone; Oxymorphone; Pain; Quality of Life; Time Factors; Tramadol
PubMed: 18443639
DOI: No ID Found -
British Journal of Clinical Pharmacology Sep 1994Concentrations of morphine, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) were measured by h.p.l.c. in plasma and cerebrospinal fluid (CSF) samples from... (Clinical Trial)
Clinical Trial
Concentrations of morphine, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) were measured by h.p.l.c. in plasma and cerebrospinal fluid (CSF) samples from 16 patients with cancer receiving oral (controlled-release) morphine. There was a close correlation between plasma and CSF morphine concentrations (r = 0.94, P = 0.0001) and both correlated with drug dosage (r = 0.61, P = 0.013 and r = 0.74, P = 0.0001, respectively). M3G and M6G in plasma and CSF were correlated (r = 0.81 and r = 0.82, both P = 0.0001). No relationship was apparent between M plus M6G concentrations in the CSF and pain scores.
Topics: Administration, Oral; Adult; Aged; Chromatography, High Pressure Liquid; Delayed-Action Preparations; Dose-Response Relationship, Drug; Female; Humans; Linear Models; Male; Middle Aged; Morphine; Morphine Derivatives; Neoplasms; Pain; Pain Measurement
PubMed: 7826830
DOI: 10.1111/j.1365-2125.1994.tb04352.x