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Mohan S, Bloom J, Kerester S, Hoffman RS, Su MK. An international survey of the treatment of massive paracetamol overdose in 2023. Clin Toxicol (Phila) 2023; 61:968-973. [PMID: 38112311 DOI: 10.1080/15563650.2023.2286922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Accepted: 11/18/2023] [Indexed: 12/21/2023]
Abstract
INTRODUCTION Changes in the commercialization of nonprescription drugs have made large quantities of paracetamol available to individuals, resulting in larger overdoses than previously observed. Although most patients with paracetamol overdose can be managed with acetylcysteine, patients with a massive overdose may become critically ill earlier and fail standard antidotal therapy. Several strategies are proposed for the management of these patients, including using increased doses of acetylcysteine, extracorporeal removal, and fomepizole. However, the benefits of these strategies remain largely theoretical, with sparse evidence for efficacy in humans. METHODS This cross-sectional study surveys international practice patterns of medical toxicology providers regarding the management of a hypothetical patient with a massive paracetamol overdose. RESULTS A total of 342 responses from 31 different nations were obtained during the study period. Sixty-one percent of providers would have increased their acetylcysteine dosing when treating the hypothetical massive overdose. Thirty percent of respondents recommended an indefinite infusion of acetylcysteine at 12.5 mg/kg/hour after the bolus dose, whereas 20 percent recommended following the "Hendrickson" protocol, which advocates for a stepwise increase in acetylcysteine dosing to match high paracetamol concentrations at the 300 mg/L, 400 mg/L, and 600 mg/L lines on the Rumack-Matthew nomogram. Ten percent of respondents stated they would have given "double dose acetylcysteine" but did not specify what that entailed. Forty-seven percent of respondents indicated that they would have given fomepizole, and 28 percent of respondents recommended extracorporeal removal. DISCUSSION Our survey study assessed the approach to a hypothetical patient with a massive paracetamol overdose and demonstrated that, at minimum, most respondents would increase the dose of acetylcysteine. Additionally, almost half would also include fomepizole, and nearly one-third would include extracorporeal removal. CONCLUSIONS There is considerable international variation for the treatment of both non-massive and massive paracetamol overdoses. Future research is needed to identify and standardize the most effective treatment for both non-massive and massive paracetamol overdoses.
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Affiliation(s)
- Sanjay Mohan
- Division of Medical Toxicology, Department of Emergency Medicine, Northwell Health, Donald and Barbara Zucker School of Medicine, Hofstra/Northwell, NY, USA
| | - Joshua Bloom
- Department of Emergency Medicine, Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Samantha Kerester
- Ronald O. Perelman Department of Emergency Medicine, NYU Grossman School of Medicine, New York, NY, USA
| | - Robert S Hoffman
- Division of Medical Toxicology, Ronald O. Perelman Department of Emergency Medicine, NYU Grossman School of Medicine, New York, NY, USA
| | - Mark K Su
- Division of Medical Toxicology, Ronald O. Perelman Department of Emergency Medicine, NYU Grossman School of Medicine, New York, NY, USA
- New York City Poison Control Center, New York, NY, USA
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Fox C, Ekaney ML, Runyon M, Nguyen HM, Turk PJ, McKillop IH, Murphy CM. Assessing Platelet Mitochondrial Dysfunction in a Murine Model of Acute Acetaminophen Toxicity. J Med Toxicol 2023; 19:341-351. [PMID: 37644341 PMCID: PMC10522545 DOI: 10.1007/s13181-023-00964-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 08/02/2023] [Accepted: 08/14/2023] [Indexed: 08/31/2023] Open
Abstract
INTRODUCTION Acetaminophen (APAP) toxicity remains a significant cause of adult and pediatric liver failure in North America and Europe. Previous research has evaluated the impaired mitochondrial function associated with APAP toxicity. The primary aim of this study was to evaluate the effects of APAP toxicity on platelet mitochondrial function using platelet oxygen consumption in a murine model in vivo. Our secondary objectives were to determine the effect of 4-MP on platelet mitochondrial function and hepatic toxicity in the setting of APAP overdose, and to correlate platelet mitochondrial function with other markers of APAP toxicity. METHODS Male C57Bl/6 mice were randomized to receive APAP (300 or 500 mg/kg) or vehicle followed 90 minutes later by either 4-MP (50 mg/kg) or vehicle via intraperitoneal injection. Mice were euthanized 0, 12, or 24 hours later and platelets isolated from cardiac blood and counted. Platelet oxygen consumption (POC) was determined using a closed-system respirometer. Liver injury was assessed by measuring alanine transferase (ALT) and histological evaluation. RESULTS Injection of 500 mg/kg APAP led to increased POC versus pair-matched control (vehicle) (p < 0.001). Administration of 4-MP did not affect POC in control or 300 mg/kg APAP mice. In mice receiving 500 mg/kg APAP and 4-MP, POC decreased significantly compared to mice receiving 500 mg/kg APAP alone (p < 0.01). Serum and histological analysis confirmed APAP-induced hepatic damage in mice receiving 500 mg/kg APAP and these effects blunted by treatment with 4-MP. CONCLUSIONS Platelet oxygen consumption as a measure of mitochondrial function may be useful as a biomarker of hepatic APAP toxicity in the setting of moderate to severe overdose. Treatment with 4-MP decreases hepatic necrosis and may mitigate the harmful effects of APAP on platelet mitochondrial function detected via POC.
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Affiliation(s)
- Carolyn Fox
- Department of Emergency Medicine, Atrium Health's Carolinas Medical Center, 1000 Blythe Blvd., Medical Education Building 3rd Floor, Charlotte, NC, 28203, USA
| | - Michael L Ekaney
- Department of Surgery, Atrium Health's Carolinas Medical Center, 1000 Blythe Blvd., Cannon Research Building, Charlotte, NC, 28203, USA
| | - Michael Runyon
- Department of Emergency Medicine, Atrium Health's Carolinas Medical Center, 1000 Blythe Blvd., Medical Education Building 3rd Floor, Charlotte, NC, 28203, USA
| | - Hieu M Nguyen
- Center for Outcomes Research and Evaluation (CORE), 1300 Scott Ave, Office 124, Charlotte, NC, 28204, USA
| | - Philip J Turk
- Department of Data Science, University of Mississippi Medical Center, 2500 N State St, Jackson, MS, 39216, USA
| | - Iain H McKillop
- Department of Surgery, Atrium Health's Carolinas Medical Center, 1000 Blythe Blvd., Cannon Research Building, Charlotte, NC, 28203, USA
| | - Christine M Murphy
- Department of Emergency Medicine, Atrium Health's Carolinas Medical Center, 1000 Blythe Blvd., Medical Education Building 3rd Floor, Charlotte, NC, 28203, USA.
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Filip AB, Mullins ME. Fomepizole should be used more liberally in paracetamol overdose. Br J Clin Pharmacol 2023; 89:594-598. [PMID: 36471569 DOI: 10.1111/bcp.15594] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 10/26/2022] [Accepted: 10/31/2022] [Indexed: 12/12/2022] Open
Abstract
Growing clinical and basic science data support the use of fomepizole as an adjunct to N-acetylcysteine in paracetamol poisoning. This safe antidote may be helpful in severely poisoned patients.
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Affiliation(s)
- Ari B Filip
- Arkansas Poison and Drug Information Center, University of Arkansas for Medical Sciences College of Pharmacy, Little Rock, Arkansas, USA
| | - Michael E Mullins
- Department of Emergency Medicine, Washington University in Saint Louis School of Medicine, Saint Louis, Missouri, USA
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Filip AB, Berg SE, Mullins ME, Schwarz ES. Fomepizole as an adjunctive therapy for acetaminophen poisoning: cases reported to the toxicology investigators consortium (ToxIC) database 2015-2020. Clin Toxicol (Phila) 2022; 60:1006-1011. [PMID: 35510880 DOI: 10.1080/15563650.2022.2070071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
INTRODUCTION Fomepizole inhibits formation of toxic acetaminophen (APAP) metabolites and may prevent or reverse mitochondrial toxicity. Given these mechanisms, it may be beneficial in patients with severe APAP toxicity. Current patterns of use for this indication are not well-studied. METHODS This is a secondary analysis of patients enrolled in the Toxicology Investigators Consortium (ToxIC) database from January 2015 to July 2020. We queried cases in which APAP was listed as an ingested agent and fomepizole was also administered. We excluded cases in which APAP was not the primary agent, N-acetylcysteine (NAC) was not administered, or fomepizole was explicitly administered for another indication. Additionally, we sent a survey to each ToxIC site that administered fomepizole for APAP toxicity to better understand when, why, and how they were using it for this indication. RESULTS Twenty-five cases of fomepizole administration following an APAP ingestion met our inclusion criteria. There were one to four cases per year between 2015 and 2019 and eight cases in 2020. Seventeen of 25 (68%) cases were for a known acute ingestion. Eighteen of 25 (72%) patients developed hepatotoxicity (AST or ALT > 1000 IU/L) and 10 of 25 (40%) developed coagulopathy (PT > 15s). This was an ill patient population, with 18 of 25 (72%) developing metabolic acidosis (pH <7.20), 12 of 25 (48%) were intubated, 9 of 25 (36%) receiving vasopressors, and 6 of 25 (24%) receiving continuous renal replacement therapy. Overall, mortality was 24%. CONCLUSION The use of fomepizole is increasing in frequency in a small subset of critically ill and acutely APAP-poisoned patients.
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Affiliation(s)
- Ari B Filip
- Department of Emergency Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Sarah E Berg
- The Toxikon Consortium, Department of Emergency Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Michael E Mullins
- Department of Emergency Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Evan S Schwarz
- Department of Emergency Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
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- American College of Medical Toxicology, Phoenix, AZ, USA
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The Roles of Antidotes in Emergency Situations. Emerg Med Clin North Am 2022; 40:381-394. [DOI: 10.1016/j.emc.2022.01.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Benić MS, Nežić L, Vujić-Aleksić V, Mititelu-Tartau L. Novel Therapies for the Treatment of Drug-Induced Liver Injury: A Systematic Review. Front Pharmacol 2022; 12:785790. [PMID: 35185538 PMCID: PMC8847672 DOI: 10.3389/fphar.2021.785790] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 12/30/2021] [Indexed: 12/15/2022] Open
Abstract
Many drugs with different mechanisms of action and indications available on the market today are capable of inducing hepatotoxicity. Drug-induced liver injury (DILI) has been a treatment challenge nowadays as it was in the past. We searched Medline (via PubMed), CENTRAL, Science Citation Index Expanded, clinical trials registries and databases of DILI and hepatotoxicity up to 2021 for novel therapies for the management of adult patients with DILI based on the combination of three main search terms: 1) treatment, 2) novel, and 3) drug-induced liver injury. The mechanism of action of novel therapies, the potential of their benefit in clinical settings, and adverse drug reactions related to novel therapies were extracted. Cochrane Risk of bias tool and Grading of Recommendations Assessment, Development and Evaluation (GRADE) assessment approach was involved in the assessment of the certainty of the evidence for primary outcomes of included studies. One thousand three hundred seventy-two articles were identified. Twenty-eight articles were included in the final analysis. Eight randomized controlled trials (RCTs) were detected and for six the available data were sufficient for analysis. In abstract form only we found six studies which were also anaylzed. Investigated agents included: bicyclol, calmangafodipir, cytisin amidophospate, fomepizole, livina-polyherbal preparation, magnesium isoglycyrrhizinate (MgIG), picroliv, plasma exchange, radix Paeoniae Rubra, and S-adenosylmethionine. The primary outcomes of included trials mainly included laboratory markers improvement. Based on the moderate-certainty evidence, more patients treated with MgIG experienced alanine aminotransferase (ALT) normalization compared to placebo. Low-certainty evidence suggests that bicyclol treatment leads to a reduction of ALT levels compared to phosphatidylcholine. For the remaining eight interventions, the certainty of the evidence for primary outcomes was assessed as very low and we are very uncertain in any estimate of effect. More effort should be involved to investigate the novel treatment of DILI. Well-designed RCTs with appropriate sample sizes, comparable groups and precise, not only surrogate outcomes are urgently welcome.
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Affiliation(s)
- Mirjana Stanić Benić
- Department of Clinical Pharmacology, Clinical Hospital Centre Rijeka, Rijeka, Croatia
| | - Lana Nežić
- Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Banja Luka, Banja Luka, Bosnia and Herzegovina
| | - Vesna Vujić-Aleksić
- Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Banja Luka, Banja Luka, Bosnia and Herzegovina
- The Republic of Srpska Agency for Certification, Accreditation and Quality Improvement in Health Care, Banja Luka, Bosnia and Herzegovina
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Mehrpour O, Saeedi F, Hadianfar A, Mégarbane B, Hoyte C. Prognostic factors of acetaminophen exposure in the United States: An analysis of 39,000 patients. Hum Exp Toxicol 2021; 40:S814-S825. [PMID: 34772307 DOI: 10.1177/09603271211061503] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Acetaminophen is a frequently used over-the-counter or prescribed medication in the United States. Exposure to acetaminophen can lead to acute liver cytolysis, acute liver failure, acute kidney injury, encephalopathy, and coagulopathy. This retrospective cohort study (1/1/2012 to 12/31/2017) investigated the clinical outcomes of intentional and unintentional acetaminophen exposure using the National Poison Data System data. The frequency of outcomes, chronicity, gender, route of exposure, the reasons for exposure, and treatments as described. Binary logistic regression was used to estimate the prognostic factors and odds ratios (OR) with 95% confidence intervals (CI) for outcomes. This study included 39,022 patients with acetaminophen exposure. Our study demonstrated that the likelihood of developing severe outcomes increased by aging (OR = 1.12, 95% CI: 1.08-1.015) and was lower in females (OR = 0.88, 95% CI: 0.78-0.99). Drowsiness/lethargy (OR = 1.48, 95% CI: 1.22-1.82), agitation (OR = 1.66, 95% CI: 1.11-2.50), coma (OR = 23.95, 95% CI: 17.05-33.64), bradycardia (OR = 2.29, 95% CI: 1.22-4.32), rhabdomyolysis (OR = 8.84, 95% CI: 3.71-21.03), hypothermia (OR = 4.1, 95% CI: 1.77-9.51), and hyperthermia 2.10 (OR = 2.10, 95% CI: 1.04-4.22) were likely associated with major outcomes or death. Treatments included intravenous N-acetylcysteine (61%), oral N-acetylcysteine (10%), vasopressor (1%), hemodialysis (0.7%), fomepizole (0.1%), hemoperfusion (0.03%), and liver transplant (0.1%). In conclusion, it is important to consider clinical presentations of patients with acetaminophen toxicity that result in major outcomes and mortality to treat them effectively.
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Affiliation(s)
- Omid Mehrpour
- Data Science Institute, Southern Methodist University, Dallas, TX, USA
| | - Farhad Saeedi
- Medical Toxicology and Drug Abuse Research Center (MTDRC), 125609Birjand University of Medical Sciences, Birjand, Iran.,Student Research Committee, 125609Birjand University of Medical Sciences, Birjand, Iran
| | - Ali Hadianfar
- Department of Biostatistics, 37552Mashhad University of Medical Sciences, Mashhad, Iran
| | - Bruno Mégarbane
- Department of Medical and Toxicological Critical Care, 378772Lariboisière Hospital, INSERM UMRS-University of Paris, Paris, France
| | - Christopher Hoyte
- Rocky Mountain Poison and Drug Center, 439895Denver Health and Hospital Authority, Denver, CO, USA.,University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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Link SL, Rampon G, Osmon S, Scalzo AJ, Rumack BH. Fomepizole as an adjunct in acetylcysteine treated acetaminophen overdose patients: a case series. Clin Toxicol (Phila) 2021; 60:472-477. [PMID: 34709101 DOI: 10.1080/15563650.2021.1996591] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
INTRODUCTION Acetaminophen (N-acetyl-para-aminophenol or APAP) is the leading cause of acute liver failure worldwide. Standard therapy for APAP overdose is with IV N-acetylcysteine (NAC). However, overdose patients treated with NAC can still incur hepatotoxicity in some circumstances. Fomepizole has proven safety in methanol and ethylene glycol poisoning and is a potent CYP2E1 and c-Jun-N-terminal Kinase (JNK) inhibitor that is effective even in the metabolic phase. METHODS We present a prospective case series of 14 consecutive, high-risk patients who had elevated APAP levels after overdose who were treated with fomepizole as an adjunct to standard IV-NAC. The attending toxicologist utilized clinical judgement to determine the use of fomepizole, especially if APAP levels persisted due to altered half-life or risk factors for toxicity. RESULTS There were no unfavorable outcomes in any patient, which were better than expected. CONCLUSIONS This case series has demonstrated the safety of fomepizole in high-risk APAP overdose. The efficacy of fomepizole needs to be further elucidated through controlled clinical trials on a larger scale. In massive APAP overdoses, fomepizole should be considered as an adjunct due to the known failure rate of NAC and the safety profile of fomepizole.
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Affiliation(s)
- Stephanie L Link
- Saint Louis University Pulmonary and Critical Care Medicine, St. Louis, MO, USA
| | - Garrett Rampon
- University of Kansas Pulmonary and Critical Care Medicine, Kansas City, MO, USA
| | - Stephen Osmon
- Former Saint Louis University Pulmonary and Critical Care Medicine, St. Louis, MO, USA
| | - Anthony J Scalzo
- Saint Louis University Division of Toxicology, St. Louis, MO, USA
| | - Barry H Rumack
- Departments of Emergency Medicine and Pediatrics, University of Colorado School of Medicine, Aurora, CO, USA
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Akakpo JY, Ramachandran A, Jaeschke H. Novel strategies for the treatment of acetaminophen hepatotoxicity. Expert Opin Drug Metab Toxicol 2020; 16:1039-1050. [PMID: 32862728 DOI: 10.1080/17425255.2020.1817896] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
INTRODUCTION Acetaminophen (APAP) hepatotoxicity is the leading cause of acute liver failure in the western world. Despite extensive investigations into the mechanisms of cell death, only a single antidote, N-acetylcysteine, is in clinical use. However, there have recently been more efforts made to translate mechanistic insight into identification of therapeutic targets and potential new drugs for this indication. AREAS COVERED After a short review of the key events in the pathophysiology of APAP-induced liver injury and recovery, the pros and cons of targeting individual steps in the pathophysiology as therapeutic targets are discussed. While the re-purposed drug fomepizole (4-methylpyrazole) and the new entity calmangafodipir are most advanced based on the understanding of their mechanism of action, several herbal medicine extracts and their individual components are also considered. EXPERT OPINION Fomepizole (4-methylpyrazole) is safe and has shown efficacy in preclinical models, human hepatocytes and in volunteers against APAP overdose. The safety of calmangafodipir in APAP overdose patients was shown but it lacks solid preclinical efficacy studies. Both drugs require a controlled phase III trial to achieve regulatory approval. All studies of herbal medicine extracts and components suffer from poor experimental design, which questions their clinical utility at this point.
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Affiliation(s)
- Jephte Y Akakpo
- Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center , Kansas City, KS, USA
| | - Anup Ramachandran
- Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center , Kansas City, KS, USA
| | - Hartmut Jaeschke
- Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center , Kansas City, KS, USA
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Mullins ME, Yeager LH, Freeman WE. Metabolic and mitochondrial treatments for severe paracetamol poisoning: a systematic review. Clin Toxicol (Phila) 2020; 58:1284-1296. [PMID: 32762579 DOI: 10.1080/15563650.2020.1798979] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Paracetamol (acetaminophen) remains a leading cause of poisoning in Europe, North America, and Australia. For over four decades, acetylcysteine has been the antidote of choice. However, despite the use of acetylcysteine, some patients who ingest very large doses of paracetamol or who reach hospital late in the course of their poisoning, develop acute liver failure. Some will develop metabolic acidosis indicating mitochondrial toxicity. OBJECTIVE We review the experimental and clinical data reported with the use of cimetidine, fomepizole, and calmangafodipir in the treatment of paracetamol toxicity to determine if these treatments alone or in combination with acetylcysteine might be of benefit. METHODS We searched Ovid Medline 1946-2020, Embase 1947-2020, Scopus 2004-2020, Cochrane Databases of Systematic Reviews (CDSR), Cochrane Central Register of Controlled Trials (CENTRAL), and clinicaltrials.gov 1997-2020 for records including the concepts of paracetamol poisoning and cimetidine, fomepizole, calmangafodipir, and acetylcysteine. We included basic science studies in animals and all available study types in humans. We reviewed the reference lists of included articles to search for references missed in the original search. We registered the protocol in PROSPERO. RESULTS We completed all search strategies on 20 August 2019, 27 January 2020, and 15 June 2020. These produced 6,826 citations. We identified and deleted 2,843 duplicate resulting in a total of 3,856 unique citations. After applying inclusion and exclusion criteria, 89 studies remained. The largest numbers of studies described the past use of cimetidine, and the more recent use of fomepizole.Cimetidine: There is good animal evidence that cimetidine blocks CYP 2E1 with the potential to inhibit the toxic metabolism of paracetamol. Early case reports were inconclusive regarding the benefit to humans in paracetamol poisoning. Two comparative trials found no benefit of cimetidine in paracetamol poisoning, but few patients had severe poisoning.Fomepizole: There is good animal evidence that fomepizole blocks CYP 2E1 with the potential to inhibit the toxic metabolism of paracetamol. There are no comparative trials of fomepizole for acute paracetamol poisoning. Case reports are inconclusive due to multiple other interventions including the use of acetylcysteine in all cases. The benefit of fomepizole as adjunct treatment has not been demonstrated.Calmangafodipir: Calmangafodipir, a drug mimicking superoxide dismutase, has emerged as a potential treatment for severe paracetamol toxicity because the formation of superoxide free radicals appears to explain part of the mitochondrial toxicity of extremely large paracetamol overdoses. Calmangafodipir has reached Phase I/II trial of safety in humans with acute paracetamol overdose. Planning for a Phase III study of efficacy is currently underway. CONCLUSIONS The vast majority of patients with acute paracetamol overdose enjoy excellent outcomes with acetylcysteine alone. Although cimetidine and fomepizole inhibit CYP 2E1 in animals, there is insufficient evidence to recommend their use either as a primary treatment or adjunct therapy in paracetamol poisoning. Calmangafodipir remains investigational.
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Affiliation(s)
- Michael E Mullins
- Section of Medical Toxicology, Department of Emergency Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Lauren H Yeager
- School of Medicine, Bernard Becker Medical Library Medicine, Washington University, St. Louis, Missouri, USA
| | - William E Freeman
- Section of Medical Toxicology, Department of Emergency Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
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Bateman DN, Dear JW, Eddleston M, Vale JA. Comment on Fomepizole as an adjunctive treatment in severe acetaminophen ingestions. Clin Toxicol (Phila) 2020; 59:81-82. [PMID: 32633659 DOI: 10.1080/15563650.2020.1788056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- D N Bateman
- Department of Pharmacology, Toxicology and Therapeutics, Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - J W Dear
- Department of Pharmacology, Toxicology and Therapeutics, Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - M Eddleston
- Department of Pharmacology, Toxicology and Therapeutics, Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - J A Vale
- City Hospital, Birmingham and University of Birmingham, Birmingham, UK
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