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BMJ Clinical Evidence Sep 2015Constipation is a common adverse effect of opioids. As an example, constipation is reported in 52% of people with advanced malignancy, and this figure rises to 87% in... (Review)
Review
INTRODUCTION
Constipation is a common adverse effect of opioids. As an example, constipation is reported in 52% of people with advanced malignancy, and this figure rises to 87% in people who are terminally ill and taking opioids. There is no reason to believe that people with chronic non-malignant disease who are prescribed opioids will be any less troubled by this adverse effect.
METHODS AND OUTCOMES
We conducted a systematic overview and aimed to answer the following clinical question: What are the effects of opioid antagonists for constipation in people prescribed opioids? The population we studied included people with any condition, although most studies were in people with cancer pain. We searched Medline, Embase, The Cochrane Library, and other important databases up to May 2014 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review).
RESULTS
At this update, searching of electronic databases retrieved 162 studies. After deduplication and removal of conference abstracts, 84 records were screened for inclusion in the review. Appraisal of titles and abstracts led to the exclusion of 47 studies and the further review of 37 full publications. Of the 37 full articles evaluated, two systematic reviews and one RCT were included at this update. We performed a GRADE evaluation for three PICO combinations.
CONCLUSIONS
In this systematic overview we categorised the efficacy for three interventions based on information relating to the effectiveness of alvimopan, methylnaltrexone, and naloxone.
Topics: Analgesics, Opioid; Constipation; Gastrointestinal Agents; Humans; Naloxone; Naltrexone; Narcotic Antagonists; Piperidines; Quaternary Ammonium Compounds; Treatment Outcome
PubMed: 26360669
DOI: No ID Found -
The Oncologist Jul 2009
Review
Topics: Humans; Laxatives; Naltrexone; Narcotic Antagonists; Quaternary Ammonium Compounds
PubMed: 19605844
DOI: 10.1634/theoncologist.2009-0049 -
Pain and Therapy Jun 2021Opioid-induced constipation (OIC) is a distressing side effect during opioid analgesia and is mainly mediated by gastrointestinal μ-opioid receptors. Methylnaltrexone,... (Review)
Review
INTRODUCTION
Opioid-induced constipation (OIC) is a distressing side effect during opioid analgesia and is mainly mediated by gastrointestinal μ-opioid receptors. Methylnaltrexone, a peripheral μ-opioid receptor antagonist with restricted ability to cross the blood-brain barrier, may alleviate OIC without reversing analgesia. We performed a meta-analysis to assess the efficacy and safety of methylnaltrexone for the treatment of OIC.
METHODS
This meta-analysis was registered in PROSPERO (CRD42020187290). We searched PubMed, Embase, and Cochrane Library for randomized controlled trials that compared methylnaltrexone with placebo for the treatment of OIC. Relative risks (RR) and 95% confidence interval (CI) were pooled using a random-effects model. We used the GRADE approach to assess the certainty of the evidence.
RESULTS
Eight trials with 2034 participants were included. Compared with placebo, methylnaltrexone significantly increased rescue-free bowel movement (RFBM) within 4 h after the first dose (eight trials; 1833 participants; RR 3.74, 95% CI 3.02-4.62; high-certainty evidence), RFBM within 24 h after the first dose (two trials; 614 participants; RR 1.98, 95% CI 1.52-2.58; moderate-certainty evidence), and RFBM ≥ 3 times per week (three trials; 1,396 participants; RR 1.33, 95% CI 1.17-1.52; moderate-certainty evidence) and decreased need to take rescue laxatives (three trials; 807 participants; RR 0.73, 95% CI 0.63-0.85; moderate-certainty evidence). For safety outcomes, there was no difference in any adverse events between the two groups (eight trials; 2034 participants; RR 1.11, 95% CI 0.99-1.23; moderate-certainty evidence), including diarrhea, nausea, vomiting, and flatulence; but for the most commonly reported adverse events, the abdominal pain was higher in methylnaltrexone group than that in placebo group (six trials; 1813 participants; RR 2.30, 95% CI 1.29-4.08; moderate-certainty evidence).
CONCLUSION
Methylnaltrexone is an effective and safe drug for the treatment of OIC, but the safety of abdominal pain should be considered.
PubMed: 33575953
DOI: 10.1007/s40122-021-00237-0 -
British Journal of Anaesthesia Jul 2011Recent introduction of new analgesics into the clinic is best described as a slow process with activity classified into two main areas: improving analgesic... (Review)
Review
Recent introduction of new analgesics into the clinic is best described as a slow process with activity classified into two main areas: improving analgesic efficacy/potency and reducing side-effect profile. This review article describes some of the recent advances with an emphasis on use in the acute setting. In this respect, opioids continue to be the mainstay (but not the only) analgesic and there have been important improvements in their clinical effect profile. For example, tapentadol has been introduced as a mixed opioid and norepinephrine uptake inhibitor which, unlike tramadol, does not require metabolic activation and does not suffer from isomer-dependent pharmacodynamics. Opioid antagonists have received much attention recently either used alone, methylnaltrexone (s.c) or alvimopan (p.o), or in combination, Targinact (oxycodone/naloxone), and appear to be effective in reducing opioid side-effects such as those in the gastrointestinal tract. Other agents where there has been recent development include the use of gabapentin, methylxanthines, and local anaesthetics. An interesting area of translation of basic research is in the inhibition of breakdown of endogenous opioids with opiorphin, targeting of the endocannabinoid system, and the use of ampakines to obtund opioid-induced side-effects. It is clear that there is still much work to be done, but the need for highly efficacious analgesics with good side-effect profile remains.
Topics: Analgesia; Analgesics; Analgesics, Non-Narcotic; Analgesics, Opioid; Chemistry, Pharmaceutical; Drug Delivery Systems; Drug Discovery; Humans
PubMed: 21624966
DOI: 10.1093/bja/aer126 -
Current Oncology Reports Oct 2022Antagonists of mu-opioid receptor role in cancer progression remains to be elucidated. The objective of this review was to summarize the available evidence on... (Review)
Review
PURPOSE OF REVIEW
Antagonists of mu-opioid receptor role in cancer progression remains to be elucidated. The objective of this review was to summarize the available evidence on antagonists of mu-opioid receptor effect on tumor progression and prognosis in different types of cancers and an evaluation of the available findings on their mechanism of action.
RECENT FINDINGS
We have found studies related to methylnaltrexone (MNTX) and naltrexone (NTX) usage in cancer outcomes-related setting. We found consistent preclinical evidence of a potential action of MNTX and NTX on cancer growth and spread mediated mainly by effect on the opioid growth factor receptor (OGFr) axis, which results in depressed cell replication. However, clinical results are scarce and limited to poor-quality evidence. Further high-quality studies are warranted to study antagonists of mu-opioid receptor role as a therapeutic option in different types of cancer, especially in patients where the classical treatment causes unacceptable side effects.
Topics: Cell Proliferation; Humans; Naltrexone; Narcotic Antagonists; Neoplasms; Quaternary Ammonium Compounds; Receptors, Opioid
PubMed: 35648340
DOI: 10.1007/s11912-022-01295-z -
Therapeutic Advances in Chronic Disease Mar 2016Currently opioids are the most frequently used medications for chronic noncancer pain. Opioid-induced constipation is the most common adverse effect associated with... (Review)
Review
Currently opioids are the most frequently used medications for chronic noncancer pain. Opioid-induced constipation is the most common adverse effect associated with prolonged use of opioids, having a major impact on quality of life. There is an increasing need to treat opioid-induced constipation. With the recent approval of medications for the treatment of opioid-induced constipation, there are several therapeutic approaches. This review addresses the clinical presentation and diagnosis of opioid-induced constipation, barriers to its diagnosis, effects of opioids in the gastrointestinal tract, differential tolerance to opiates in different gastrointestinal organs, medications approved and in development for the treatment of opioid-induced constipation, and a proposed clinical management algorithm for treating opioid-induced constipation in patients with noncancer pain.
PubMed: 26977281
DOI: 10.1177/2040622315627801 -
American Journal of Physiology.... Oct 2021Remifentanil impairs swallowing, and disturbed accommodation to bolus volume may be one of the underlying causes. It is not fully understood whether remifentanil-induced... (Clinical Trial)
Clinical Trial
Remifentanil impairs swallowing, and disturbed accommodation to bolus volume may be one of the underlying causes. It is not fully understood whether remifentanil-induced swallowing dysfunction is mediated by peripheral or central mechanisms. So, this study aimed to investigate if remifentanil-induced swallowing dysfunction is dependent on the bolus volume and whether the effect of remifentanil could be counteracted by methylnaltrexone, a peripherally acting opioid antagonist. Nineteen healthy volunteers were included in this double-blinded, randomized, placebo-controlled, crossover study. Study participants received target-controlled remifentanil infusions and placebo infusions in a randomized order. Methylnaltrexone was administered by intravenous injection of doses of 0.3 mg/kg. Recordings of pressure and impedance data were acquired using a combined manometry and impedance solid-state catheter. Data were analyzed from three series of bolus swallows, baseline, during study medication exposure, and 15 min after methylnaltrexone. Remifentanil induced significant effects on multiple pharyngeal and esophageal function parameters. No significant differences in remifentanil-induced swallowing dysfunction related to different bolus volumes were found. Pharyngeal effects of remifentanil were not significantly counteracted by methylnaltrexone, whereas on the distal esophageal level, effects on distension pressures were counteracted. Changes in pharyngeal and esophageal pressure flow variables were consistent with previous results on remifentanil-induced swallowing dysfunction and uniform across all bolus volumes. The effects of remifentanil on the pharyngeal level and on the proximal esophagus appear to be predominantly centrally mediated, whereas the effects of remifentanil on the distal esophagus may be mediated by both central and peripheral mechanisms. In this randomized controlled trial, we used the "Swallow Gateway" online platform to analyze the effects of remifentanil on pharyngeal and esophageal swallowing. It is not fully understood whether remifentanil-induced swallowing dysfunction is mediated by peripheral or central mechanisms. By using methylnaltrexone, we demonstrated that effects of remifentanil on pharyngeal swallowing were predominantly centrally mediated, whereas its effects on the distal esophagus may be mediated by both central and peripheral mechanisms.
Topics: Adult; Analgesics, Opioid; Deglutition; Drug Antagonism; Esophagus; Female; Healthy Volunteers; Humans; Injections, Intravenous; Male; Muscle Contraction; Muscle Relaxation; Naltrexone; Narcotic Antagonists; Pharynx; Quaternary Ammonium Compounds; Remifentanil
PubMed: 34261364
DOI: 10.1152/ajpgi.00137.2021 -
Therapeutic Advances in Gastroenterology Sep 2016Opioid-induced constipation (OIC) and other gastrointestinal (GI) symptoms of opioid-induced bowel dysfunction (OIBD) significantly deteriorate patients' quality of life... (Review)
Review
Opioid-induced constipation (OIC) and other gastrointestinal (GI) symptoms of opioid-induced bowel dysfunction (OIBD) significantly deteriorate patients' quality of life and may lead to noncompliance with opioid schedule and undertreatment of pain. Although traditional oral laxatives are the first-line treatment of OIC, they do not address OIBD pathophysiology, and display numerous adverse effects. OIC treatment includes prokinetics (lubiprostone), opioid switch, and changing route of opioid administration. Targeted management of OIBD comprises the use of purely peripherally acting μ-opioid receptor antagonists (PAMORA): naloxegol and methylnaltrexone. Naloxegol (NKTR-118) is a polymer conjugate of the opioid antagonist naloxone. The polyethylene glycol limits naloxegol capacity to cross the blood-brain barrier (BBB). Naloxegol is substrate for the P-glycoprotein (P-gp) transporter. The central nervous system penetration of naloxegol is negligible due to reduced permeability and its increased efflux across the BBB, related to P-gp transporter. Naloxegol antagonizes μ- and κ-opioid receptors and displays low affinity to δ-opioid receptors in the GI tract, thereby decreasing OIBD symptoms without reversing central analgesic effects. Naloxegol is metabolised through CYP3A4 to six metabolites, with the majority of the dose (68%) excreted with faeces and less (16%) with urine. The dose of naloxegol equals 25 mg administered orally once daily on a fasting condition. Mild or moderate hepatic impairment has no impact on naloxegol dosing; naloxegol was not studied and is not recommended in patients with hepatic failure. Dose reduction (12.5 mg once daily) and caution is recommended in patients with moderate-to-severe renal impairment. Efficacy (bowel movement in 42-49% of patients not responsive to laxatives) and safety of naloxegol were confirmed in studies conducted in patients with OIC and nonmalignant pain. Naloxegol may be useful for cancer patients with OIC, although studies in this population are lacking.
PubMed: 27582887
DOI: 10.1177/1756283X16648869 -
The Journal of Pediatric Pharmacology... 2022To evaluate the association between methylnaltrexone and urine output (UOP) in critically ill children with opioid-associated urinary retention.
OBJECTIVE
To evaluate the association between methylnaltrexone and urine output (UOP) in critically ill children with opioid-associated urinary retention.
METHODS
This retrospective study included patients admitted to the pediatric intensive care unit between December 1, 2019, and November 30, 2020, who received methylnaltrexone for opioid-associated oliguria (spontaneous UOP below 1 mL/kg/hr and at least 1 dose of an opioid within the preceding 6 hours).
RESULTS
Twenty-five patients (median age = 5.5 years, IQR 1.7-16.4; median weight = 19 kg, IQR 9-45) were included. Mean methylnaltrexone dose was 0.15 ± 0.006 mg/kg. A statistically significant increase in UOP from baseline to 6 hours following methylnaltrexone was observed (p = 0.001), but not all patients responded. Fourteen patients (56%) had no UOP following methylnaltrexone administration, while 11 (44%) demonstrated a robust increase (median = 0 mL/kg/hr at baseline [IQR 0-0] to 1.96 mL/kg/hr [IQR 1.08-2.22; p = 0.001]) within 6 hours following methylnaltrexone administration. Younger patients responded better than older patients (responder age = 2.5 years [IQR 0.8-7]) versus 11.4 years [IQR 1.75-17.5] for non-responders) (p = 0.04). Both intravenous (IV) and subcutaneous (SQ) routes were associated with an increase in UOP (IV, p = 0.04; SQ, p = 0.02). The effect persisted for up to 24 hours after administration. Sixty-four percent of patients required urinary catheter placement. Pain scores (averaged 6 hours before and after methylnaltrexone) remained unchanged (p = 0.44).
CONCLUSIONS
Methylnaltrexone may increase spontaneous UOP in some children with opioid-associated urinary retention, but urinary catheterization rates remain high.
PubMed: 35558358
DOI: 10.5863/1551-6776-27.4.373 -
Visceral Medicine Apr 2018Chronic constipation is a very common medical problem with relevant impact on the patients' quality of life. Modern definitions recognize constipation as a... (Review)
Review
Chronic constipation is a very common medical problem with relevant impact on the patients' quality of life. Modern definitions recognize constipation as a polysymptomatic disorder, including various aspects of disturbed defecation. Current guidelines recommend a stepwise approach in the management of chronic constipation. Isolated or concomitant evacuation disorders should be identified and may need differential/additional treatment. Baseline measures include lifestyle components and bulking agents. The next step recommends treatment with conventional laxatives. In refractory patients, modern medical therapies, such as the prokinetic prucalopride or the secretagogues linalotide or lubiprostone, may be used effectively. For patients with opioid-induced constipation, the modern concept of peripherally acting µ-opioid antagonists has shown to successfully improve this increasing medical problem and even to potentially increase survival time in terminally ill patients on opioid therapy. Prolonged-released oral naloxone (in fixed combination with oxycodone), oral naloxegol or naldemedine, and subcutaneous methylnaltrexone have all demonstrated good efficacy and tolerability in the treatment of opioid-induced constipation. To adequately apply stepwise treatment algorithms, a simple tool to identify treatment failure may improve patient care.
PubMed: 29888241
DOI: 10.1159/000488695