Position statement and practice guidelines on the use of multi-dose activated charcoal in the treatment of acute poisoning. American Academy of Clinical Toxicology; European Association of Poisons Centres and Clinical Toxicologists

A case of multiorgan failure due to carbamazepine intoxication successfully treated with multimodal blood purification therapy

Carbamazepine (CBZ) intoxication can occur due to various factors, including drug interactions and over-ingestion. Extracorporeal elimination, particularly through hemodialysis and hemoperfusion, is effective in treating severe carbamazepine intoxication. However, as the effectiveness of various modalities can differ, method selection may be based on a specific clinical situation. A 47-year-old woman who took CBZ for schizophrenia presented to our hospital with episodes of vomiting and consciousness disorder. As the CBZ concentration was > 20 μg/mL, she was admitted to the intensive care unit with a diagnosis of acute CBZ poisoning. She underwent one session of hemoperfusion for 2 h, and her CBZ level decreased from > 20 µg/mL to 6.4 µg/mL. However, she developed acute kidney and liver injuries 2 days after admission and underwent intermittent hemodialysis, plasma exchange, continuous hemodiafiltration (CHDF), and online HDF, depending on her condition. Her general condition improved, and she was transferred to the psychiatric department. To our knowledge, no case reports have described severe acute CBZ poisoning in a patient who developed multiorgan failure to date, which was successfully treated with multimodal blood purification therapy. When treating severe CBZ intoxication, blood purification therapy should be tailored to the changing pathophysiology of the condition.

Critical care management of acute intoxications, dynamics and changes over time: a cohort study

Acute intoxications and poisonings are a relevant cause for ICU admission of critically ill patients. This study aimed to determine the characteristics of intoxicated patients in a tertiary center medical ICU in Austria over time and to investigate parameters associated with ICU mortality. This study was a retrospective data analysis including adult ICU patients from the years 2007 to 2021. In addition to ICU documentation, pre-hospital, and emergency department documents as well as autopsy reports were utilized. In an exploratory subanalysis, we compared these findings to a historical dataset from our facility from 1992 to 1996. We identified 581 cases admitted to the medical ICU because of acute poisoning (2007-2021), of which 45% were female and 46.6% were mixed intoxications. Suicidal intent was the primary cause of intoxication (48.2%) and ICU length of stay was median 1.2 days. The majority of deceased patients received pre-hospital mechanical CPR. Primary and secondary poison/toxin removal modalities were used in 29.9% and 11.7% of cases, whereas antidotes were administered in 54.4%. Comparing the data with a historical cohort (n = 168), we found a shift in primary detoxification away from gastric lavage and an increase in alternative secondary poison/toxin removal techniques. The ICU mortality was 4.1% and 4.2% in the present and historic cohort, respectively. Pre-existing psychiatric illnesses increased from 49% in the historic to 69% in the present cohort. Psychiatric illness predisposes patients to severe intoxications necessitating ICU care, thus increasing prevention measures seems warranted. Females did present with a different spectrum of intoxications compared to males. ICU mortality remained low over time and most deceased patients had a grim prognosis already on ICU arrival.

Principal causes of acute poisoning in an emergency service: experience between 2014 and 2021 at a University Hospital in Southwestern Colombia

Acute poisonings are a global public health problem, which implies costs and disease burden for society. In Colombia, there is a significant underreporting of data on acute poisoning and data gaps on the toxicological profile of the population. This study aims to identify the epidemiology of acute poisoning in a high-complexity hospital in southwestern Colombia. A descriptive study with retrospective data collection was performed. The variables were expressed through the measure of central tendency and dispersion. Categorical variables were described in proportions. A total of 406 patients were included. The median age was 31 years (IQR 23-48), 56.2% were male, and only 19.2% had a history of mental illness. Suicidal intent represented 58.8% of the cases, and the most frequent route of exposure was the oral route (81.6%). The most prevalent groups of substances were pesticides (34.2%) and medicines (32%). The most common etiological agent was organophosphates (16.5%). Cholinergic toxidrome was the most common. The average stay in the ICU was 4.5 days (± 4.8), and the mortality was 4.2%. The principal causes of acute poisoning were drugs and pesticides, with a predominant etiology of organophosphates and depressants of the central nervous system. There was a significant predominance of young male patients with suicidal intent, low mental disorders, elevated unemployment rate, and similar mortality reported in other studies. This study improves the knowledge about acute poisoning in southwestern Colombian to carry out multicenter analytic studies.

Management of acute carbamazepine poisoning: A narrative review

Standard management protocols are lacking and specific antidotes are unavailable for acute carbamazepine (CBZ) poisoning. The objective of this review is to provide currently available information on acute CBZ poisoning, including its management, by describing and summarizing various therapeutic methods for its treatment according to previously published studies. Several treatment methods for CBZ poisoning will be briefly introduced, their advantages and disadvantages will be analyzed and compared, and suggestions for the clinical treatment of CBZ poisoning will be provided. A literature search was performed in various English and Chinese databases. In addition, the reference lists of identified articles were screened for additional relevant studies, including non-indexed reports. Non-peer-reviewed sources were also included. In the present review, 154 articles met the inclusion criteria including case reports, case series, descriptive cohorts, pharmacokinetic studies, and in vitro studies. Data on 67 patients, including 4 fatalities, were reviewed. Based on the summary of cases reported in the included articles, the cure rate of CBZ poisoning after symptomatic treatment was 82% and the efficiency of hemoperfusion was 58.2%. Based on the literature review, CBZ is moderately dialyzable and the recommendation for CBZ poisoning is supportive management and gastric lavage. In severe cases, extracorporeal treatment is recommended, with hemodialysis as the first choice.

Management of Poisonings and Intoxications

Poisoning occurs after exposure to any of a number of substances, including medicines, which can result in severe toxicity including death. The nephrologist may be involved in poisonings that cause kidney disease and for targeted treatments. The overall approach to the poisoned patient involves the initial acute resuscitation and performing a risk assessment, whereby the exposure is considered in terms of the anticipated severity and in the context of the patient's status and treatments that may be required. Time-critical interventions such as gastrointestinal decontamination ( e.g. , activated charcoal) and antidotes are administered when indicated. The nephrologist is usually involved when elimination enhancement techniques are required, such as urine alkalinization or extracorporeal treatments. There is increasing data to guide decision making for the use of extracorporeal treatments in the poisoned patient. Principles to consider are clinical indications such as whether severe toxicity is present, anticipated, and/or will persist and whether the poison will be significantly removed by the extracorporeal treatment. Extracorporeal clearance is maximized for low-molecular weight drugs that are water soluble with minimal protein binding (<80%) and low endogenous clearance and volume of distribution. The dosage of some antidotes ( e.g. , N-acetylcysteine, ethanol, fomepizole) should be increased to maintain therapeutic concentrations once the extracorporeal treatment is initiated. To maximize the effect of an extracorporeal treatment, blood and effluent flows should be optimized, the filter with the largest surface area selected, and duration tailored to remove enough poison to reduce toxicity. Intermittent hemodialysis is recommended in most cases when an extracorporeal treatment is required because it is the most efficient, and continuous kidney replacement therapy is prescribed in some circumstances, particularly if intermittent hemodialysis is not readily available.

Patterns of acute poisoning for children during outbreak of Corona virus in Makkah region Saudi Arabia

Background

Poisoning occurs when a person is exposed to an external substance at a too high dose for them. It is possible for young children to be exposed to chemicals. Lungs, the heart, CNS, the digestive tract, and kidneys can be poisoned. In 2004, over 45,000 children and teenagers died from acute poisoning, representing 13% of all accidental poisoning deaths worldwide. Poisoning patterns vary by exposure type, age group, poison type, and dose.

Aim

This study assessed the pattern of acute poisoning with drugs, chemicals, and natural toxins among children (<12 years old). The study was done in Makkah region and registered in the poison control center in Makkah, the forensic chemistry center in Haddah during 2020-2021.

Methods

A retrospective cohort study was done on 122 children exposed to toxic substances in Makkah. The children were 12 years old and had good health for a maximum of one year. Stratified random sampling was used to divide cases into groups of similar poisons (pharmaceutical products, household products, plant envenomation, and animal envenomation). Then each group got a random samples. The data were analysed with SPSS software.

Results

The mean age of children was 5.2 years, with 59% being boys. The mean temperature, pulse, systolic, diastolic, and respiratory rates were 36.77, 98.29, 109.1, 69.17, and 21.49. The most documented pharmaceutical products (200 mg) were carbamazepine (5 mg), methanol, risperidone (5 mg), propranolol (5 mg), and olanzapine (5 mg). The most common poison forms were tablets (42.6%), syrups (15.6%), capsules (13.9%), and solutions (13.1%). The most common poisoning routes were ingestion (82.8%), dermal (5.7%), injection (4.9%), and inhalation (6.6%). Accidental poisoning was 83%, with a 30-minute lag for 30.3% of children, and most (69.7%) occurred at home. Benzodiazepines were the most commonly used category class drug (18%), with normal pupils and an ECG of 85.2%. Sixty-seven percent had blood tests. Sickness was 9.48, and the positive result was 213.01. The most common presenting symptoms were GIT and neurological (23.8%). 31.1% had mild, moderate, or severe toxicity. Most cases (68%) were complex. 34.4% were intubated, 9.8% had repeated-dose-activated charcoal for enhanced elimination, and 27.8% were on IV fluids. Children with GIT, CVS, respiratory, dermal, and neurological symptoms had a higher percentage of severe toxicity (p < 0.05). Slight toxicity was associated with whole bowel irrigation, intubation for oxygen therapy, N-acetylcysteine or sedation, fluids, and phenytoin (P < 0.05). Complicated cases had a higher mean AST/IUL than non-complicated cases (75.5 vs. 20.08, p < 0.05). The level of toxicity did not correlate with the mean of all lab tests (p > 0.05). The age of the children correlated positively with their systolic BP (r = 0.22, p < 0.01).

Conclusion

The results show how important it is to teach the public about poisoning and make rules for tracking and dealing with poisonings in Saudi Arabia.

Pesticide exposure and poisoning in Brazil: Outcome severity, clinical manifestations and management of cases reported to a poison control center

This work aimed to identify variables associated with increased risk of outcome severity as well as to describe clinical manifestations/symptoms and management of pesticide-related cases reported to a poison center in Brazil. An increased risk of more severe outcomes was observed when exposures occurred in rural areas, involved suicide attempts and moderately to extremely hazardous pesticides. Clinical manifestations with higher frequencies included vomiting, nausea, sialorrhea, headache, miosis and sweating. From the treatment initially applied to the patient, 51.91% encompassed gastric lavage, but this procedure was only recommended in 20.01% of cases by the CIATox. Identifying risk factors associated with poor outcome, describing clinical manifestations, and contrasting initial treatment measures adopted against those recommended by the Poison Center can help determine diagnosis, prognosis and ensure appropriate clinical interventions are used in cases of pesticide poisoning.

Clinical and sociodemographic profile of acute intoxications in an emergency department: A retrospective cross-sectional study

Background

Epidemiological studies about acute poisoning are useful for developing clinical toxicology, especially those carried out in hospital emergency departments. We aimed to evaluate acute intoxication clinical and sociodemographic profile in South Aragon Hospital, Spain.

Methods

We carried out a retrospective cross-sectional study. We included 442 patients treated for acute poisoning in the emergency department during the 3 years 2015-2018. In the inferential analysis, the Chi-square test was used to compare proportions, and the Mann-Whitney U-test was used to compare ranges. A confidence level of 95 per cent was considered in all tests.

Results

The mean age was 44.1 years. 57.2% were men. Drugs of abuse were present in 243 patients (55%), drugs in 172 (38.9%), chemicals in 57 (12.9%) and three patients (0.7%) were poisoned by mushrooms. Nine different drugs of abuse, 73 drugs, 15 chemical compounds and 2 varieties of mushrooms were registered. Of the intoxicated patients, 92.3% had symptoms, 84.2% received treatment and 78.7% were discharged from the emergency department.

Conclusions

We obtain a clear clinical and sociodemographic profile of intoxicated patients who come to the emergency department; the five toxins that cause most acute poisoning are: alcohol, benzodiazepines, antiarrhythmics, cannabis and carbon monoxide.

Clinical Features, Intensive Care Needs, and Outcome of Carbamazepine Poisoning in Children

Carbamazepine is commonly used antiseizure medication with a narrow therapeutic range. The data on carbamazepine poisoning in children from India is limited. In this retrospective study, the authors reported 10 children with carbamazepine poisoning admitted to pediatric intensive care unit (PICU) of a tertiary care teaching hospital in North India over a period of 8 y (2013 to 2020). The median age was 5.5 (4.3-6) y and 60% cases were males. All had accidental ingestion and the dose ingested was 96 (80-103) mg/kg. The common clinical features were drowsiness (100%), tachycardia (80%), vomiting (60%), seizures (60%), respiratory failure (60%), and dystonia (50%). At admission, 60% children had coma. The treatment included gastric lavage (70%), single-dose-activated charcoal (60%), multidose-activated charcoal (30%), mechanical ventilation (60%), and dialysis (20%). The duration of PICU and hospital stay was 36 (22-45) h and 48 (48-60) h, respectively. There was no mortality.

Poisoning by Plants

BACKGROUND

Questions on poisoning by plants are a common reason for inquiries to poison information centers (PIC). Over the years 2011-2020, plant poisoning was the subject of 15% of all inquiries to the joint poison information center in Erfurt, Germany (Gemeinsames Giftinformationszentrum Erfurt, GGIZ) that concerned poisoning in children (2.3% in adults). In this patient collective, plant poisoning occupied third place after medical drugs (32%) and chemical substances (24%), and was a more common subject of inquiry than mushroom poisoning (1.5%).

METHODS

This review is based on pertinent publications retrieved by a selective literature search in PubMed/TOXLINE on plant poisoning and on 12 epidemiologically and toxicologically relevant domestic species of poisonous plants in risk categories 2 and 3 (up to 2021).

RESULTS

Medical personnel should have basic toxicological knowledge of the following highly poisonous plants: wolfsbane (aconitum), belladonna, angel's trumpet, cowbane (cicuta virosa), autumn crocus, hemlock, jimson weed, henbane, castor bean (ricinus), false hellebore, foxglove (digitalis), and European yew. The intoxication is evaluated on the basis of a structured history (the "w" questions) and the clinical manifestations (e.g., toxidromes). Special analysis is generally not readily available and often expensive and time-consuming. In case of poisoning, a poison information center should be contacted for plant identification, risk assessment, and treatment recommendations. Specimens of plant components and vomit should be obtained, if possible, for further testing. Measures for the elimination of the poisonous substance may be indicated after a risk-benefit analysis. Specific antidotes are available for only a few types of plant poisoning, e.g., physostigmine for tropane alkaloid poisoning or digitalis antibodies for foxglove poisoning. The treatment is usually symptomatic and only rarely evidence-based. Individualized medical surveillance is recommended after the ingestion of large or unknown quantities of poisonous plant components.

CONCLUSION

The clinician should be able to recognize dangerous domestic species of poisonous plants, take appropriate initial measures, and avoid overdiagnosis and overtreatment. To improve patient care, systematic epidemiological and clinical studies are needed.

Systematic review on the use of activated charcoal for gastrointestinal decontamination following acute oral overdose

INTRODUCTION

The use of activated charcoal in poisoning remains both a pillar of modern toxicology and a source of debate. Following the publication of the joint position statements on the use of single-dose and multiple-dose activated charcoal by the American Academy of Clinical Toxicology and the European Association of Poison Centres and Clinical Toxicologists, the routine use of activated charcoal declined. Over subsequent years, many new pharmaceuticals became available in modified or alternative-release formulations and additional data on gastric emptying time in poisoning was published, challenging previous assumptions about absorption kinetics. The American Academy of Clinical Toxicology, the European Association of Poison Centres and Clinical Toxicologists and the Asia Pacific Association of Medical Toxicology founded the Clinical Toxicology Recommendations Collaborative to create a framework for evidence-based recommendations for the management of poisoned patients. The activated charcoal workgroup of the Clinical Toxicology Recommendations Collaborative was tasked with reviewing systematically the evidence pertaining to the use of activated charcoal in poisoning in order to update the previous recommendations.

OBJECTIVES

The main objective was: Does oral activated charcoal given to adults or children prevent toxicity or improve clinical outcome and survival of poisoned patients compared to those who do not receive charcoal?  Secondary objectives were to evaluate pharmacokinetic outcomes, the role of cathartics, and adverse events to charcoal administration. This systematic review summarizes the available evidence on the efficacy of activated charcoal.

METHODS

A medical librarian created a systematic search strategy for Medline (Ovid), subsequently translated for Embase (via Ovid), CINAHL (via EBSCO), BIOSIS Previews (via Ovid), Web of Science, Scopus, and the Cochrane Library/DARE. All databases were searched from inception to December 31, 2019. There were no language limitations.  One author screened all citations identified in the search based on predefined inclusion/exclusion criteria. Excluded citations were confirmed by an additional author and remaining articles were obtained in full text and evaluated by at least two authors for inclusion. All authors cross-referenced full-text articles to identify articles missed in the searches. Data from included articles were extracted by the authors on a standardized spreadsheet and two authors used the GRADE methodology to independently assess the quality and risk of bias of each included study.

RESULTS

From 22,950 titles originally identified, the final data set consisted of 296 human studies, 118 animal studies, and 145 in vitro studies. Also included were 71 human and two animal studies that reported adverse events. The quality was judged to have a Low or Very Low GRADE in 469 (83%) of the studies. Ninety studies were judged to be of Moderate or High GRADE. The higher GRADE studies reported on the following drugs: paracetamol (acetaminophen), phenobarbital, carbamazepine, cardiac glycosides (digoxin and oleander), ethanol, iron, salicylates, theophylline, tricyclic antidepressants, and valproate. Data on newer pharmaceuticals not reviewed in the previous American Academy of Clinical Toxicology/European Association of Poison Centres and Clinical Toxicologists statements such as quetiapine, olanzapine, citalopram, and Factor Xa inhibitors were included. No studies on the optimal dosing for either single-dose or multiple-dose activated charcoal were found. In the reviewed clinical data, the time of administration of the first dose of charcoal was beyond one hour in 97% (n = 1006 individuals), beyond two hours in 36% (n = 491 individuals), and beyond 12 h in 4% (n = 43 individuals) whereas the timing of the first dose in controlled studies was within one hour of ingestion in 48% (n = 2359 individuals) and beyond two hours in 36% (n = 484) of individuals.

CONCLUSIONS

This systematic review found heterogenous data. The higher GRADE data was focused on a few select poisonings, while studies that addressed patients with unknown and or mixed ingestions were hampered by low rates of clinically meaningful toxicity or death.  Despite these limitations, they reported a benefit of activated charcoal beyond one hour in many clinical scenarios.

Approach to Toxicologic Emergencies

Equine toxicologic emergencies are relatively uncommon but can cause significant morbidity and mortality in a group of comanaged horses. The field veterinarian's role is to triage the situation, as well as the individual animal. Individual patient stabilization should focus on support of essential organ functions, providing time for treatments to have an effect or for elimination of the toxicant. Decontamination procedures can follow patient stabilization, if appropriate. Antidotes are often not available or feasible for equine intoxications. The field veterinarian should emphasize triage and stabilization before referral and on-site identification and collection of diagnostic samples to support the diagnosis.

The effect of activated charcoal on drug exposure following intravenous administration: A meta-analysis

Activated charcoal both reduces primary drug absorption and enhances drug elimination. However, the two mechanisms of action overlap and are indistinguishable from each other. In order to estimate the extend of enhanced elimination, we summarized the effect of activated charcoal on intravenously administered drugs, where reduced drug exposure can be attributed to enhanced elimination. We performed a meta-analysis of randomized controlled studies evaluating the effect of orally administered activated charcoal on the systemic exposure of intravenously administered drugs. We searched the bibliographic databases PubMed, Embase and Cochrane. Meta-regression analyses of selected physiochemical drug properties on the effect sizes of activated charcoal were performed. All but one of 21 included studies used multiple-dose activated charcoal (MDAC). MDAC reduced the median half-life of the intravenously administered study drugs by 45.7% (interquartile range: 15.3%-51.3%) and area under the concentration time curve by 47.0% (interquartile range: 36.4%-50.2%). MDAC significantly improved drug elimination across nine different intravenously administered drugs, but we were unable to identify factors allowing extrapolation to other drugs. The results offer a possible and plausible rationale for the previously observed effects of single-dose activated charcoal beyond the timeframe where ingested drug is present in the gastro-intestinal tract.

Management of pharmaceutical and recreational drug poisoning

BACKGROUND

Poisoning is one of the leading causes of admission to the emergency department and intensive care unit. A large number of epidemiological changes have occurred over the last years such as the exponential growth of new synthetic psychoactive substances. Major progress has also been made in analytical screening and assays, enabling the clinicians to rapidly obtain a definite diagnosis.

METHODS

A committee composed of 30 experts from five scientific societies, the Société de Réanimation de Langue Française (SRLF), the Société Française de Médecine d'Urgence (SFMU), the Société de Toxicologie Clinique (STC), the Société Française de Toxicologie Analytique (SFTA) and the Groupe Francophone de Réanimation et d'Urgences Pédiatriques (GFRUP) evaluated eight fields: (1) severity assessment and initial triage; (2) diagnostic approach and role of toxicological analyses; (3) supportive care; (4) decontamination; (5) elimination enhancement; (6) place of antidotes; (7) specificities related to recreational drug poisoning; and (8) characteristics of cardiotoxicant poisoning. Population, Intervention, Comparison, and Outcome (PICO) questions were reviewed and updated as needed, and evidence profiles were generated. Analysis of the literature and formulation of recommendations were then conducted according to the GRADE® methodology.

RESULTS

The SRLF-SFMU guideline panel provided 41 statements concerning the management of pharmaceutical and recreational drug poisoning. Ethanol and chemical poisoning were excluded from the scope of these recommendations. After two rounds of discussion and various amendments, a strong consensus was reached for all recommendations. Six of these recommendations had a high level of evidence (GRADE 1±) and six had a low level of evidence (GRADE 2±). Twenty-nine recommendations were in the form of expert opinion recommendations due to the low evidences in the literature.

CONCLUSIONS

The experts reached a substantial consensus for several strong recommendations for optimal management of pharmaceutical and recreational drug poisoning, mainly regarding the conditions and effectiveness of naloxone and N-acetylcystein as antidotes to treat opioid and acetaminophen poisoning, respectively.

The Use of Activated Charcoal to Treat Intoxications

BACKGROUND

In 2016, according to the German Federal Statistical Office, 178 425 cases of intoxication (poisoning) were treated in German hospitals. The poison control centers in the German-speaking countries gave advice in a total of 268 787 instances of poisoning in that year, and use of activated charcoal was recommended in 4.37% of cases. The application of activated charcoal plays a major role in both primary and secondary detoxification. This article serves as an overview of the mechanism of action, indications, contraindications, modes of application, and dosing of activated charcoal.

METHODS

This review is based on pertinent publications retrieved by a selective search in PubMed. The opinions of experts from the poison control centers in the German-speaking countries were considered in the interpretation of the data.

RESULTS

The administration of activated charcoal is indicated to treat moderately severe to life-threatening intoxication. It should be carried out as soon as possible, within the first hour of the ingestion; timed-release preparations can be given up to 6 hours after the ingestion. An important contraindication is impaired consciousness with the danger of aspiration in a patient whose air- way has not yet been secured. Activated charcoal is ineffective or inadequately effective in cases of poisoning with acids or bases, alcohols, organic solvents, inorganic salts, or metals. The proper dosage consists of an amount that is 10 to 40 times as much as that of the intoxicating substance, or else 0.5-1 g/kg body weight in children or 50 g in adults. Repeated application is indicated for intoxications with agents that persist for a longer time in the stomach and for intoxications with timed-release drugs or drugs with a marked enterohepatic or entero-enteric circulation. The routine combination of activated charcoal with a laxative is not recommended.

CONCLUSION

Even though intoxications are common, there is still no internationally valid guideline concerning the administration of activated charcoal. A precise analysis of the risks and benefits is needed for each administration, and a poison control center should be consulted for this purpose.

Carbamazepine Toxicity Masquerading as Complex Febrile Seizures in a Pediatric Patient

Carbamazepine is an antiepileptic drug that can cause seizures in overdose. In certain patient populations, this may be misdiagnosed as a seizure disorder. We describe a case of a 20-month-old female who presented with fever and seizure-like activity who was initially thought to have complex febrile seizures. Further historical information prompted carbamazepine level to be checked, which was found to be 29 mcg/ml (therapeutic range of 4–12 mcg/ml). Her carbamazepine levels downtrended with multidose activated charcoal. Her condition improved, and she was discharged without evidence of permanent neurologic sequelae. This case illustrates that xenobiotic exposure should often be considered, even if historical clues are not present, as they can often present as other conditions leading to misdiagnosis and delayed treatment.

[Diagnostics and treatment of selected clinically relevant, acute drug intoxications]

Acute drug poisoning due to accidental or self-damaging overdoses is responsible for 5-10% of emergency medical interventions in Germany. The treatment of asymptomatic to life-threatening courses requires extensive expertise. On the basis of a selective literature search, this article gives an overview of selected clinically relevant, acute drug poisonings with regard to epidemiology, symptomatology, diagnostics, and therapy.Intoxications with psychotropic drugs are the most common drug intoxications. Poisoning with tricyclic antidepressants causes anticholinergic, central nervous, and cardiovascular symptoms. Less toxic are selective serotonin reuptake inhibitors (SSRIs); the intoxication may be characterized by serotonin syndrome. Malignant neuroleptic syndrome is a severe complication of neuroleptic poisoning.Poisoning with analgesics is clinically relevant due to its high availability. For paracetamol poisoning, intravenous acetylcysteine is available as an antidote. Hemodialysis may be indicated for severe salicylate intoxication. Poisoning with nonsteroidal anti-inflammatory drugs is usually only associated with mild signs of intoxication.Poisoning with cardiac drugs (β-blockers and calcium antagonists) can cause life-threatening cardiovascular events. In addition to symptomatic therapy, insulin glucose therapy also plays an important role.The majority of acute drug poisonings can be treated adequately by symptomatic and partly intensive care therapy - if necessary with the application of primary and secondary toxin elimination. Depending on the severity of the intoxication, pharmacology-specific therapy must be initiated.

[Acute intoxications: markers for screening, diagnosis and therapy monitoring]

Acute poisonings account for a significant proportion of the patient population presenting to intensive care units, whereby mixed drug overdoses and prescription drug overdoses predominate. The aim of this article was to describe indications for screening, diagnosis and therapy monitoring in acute overdoses in the intensive care unit. To conduct this work, a literature search was carried out and a review was written based on guidelines, case reports, expert opinions and scientific publications. Toxidromes are a useful tool for classification of clinical characteristics when the causative agent is initially unknown. Especially in critical care medicine, identifying and quantifying of the causative toxin by enzyme immunoassays, chromatography and mass spectrometry should be attempted. Intensive care treatment of patients with acute overdoses includes not only monitoring and support of vital functions but also methods for primary and secondary elimination of toxins. The indication for the use of extracorporeal procedures should be carefully evaluated and the method should be chosen based on protein binding and molecular size. Lipid emulsion therapy, high-dose insulin euglycaemia therapy and hyperbaric oxygenation are also increasingly used.

Antidotes in Poisoning

Introduction

Antidotes are agents that negate the effect of a poison or toxin. Antidotes mediate its effect either by preventing the absorption of the toxin, by binding and neutralizing the poison, antagonizing its end-organ effect, or by inhibition of conversion of the toxin to more toxic metabolites. Antidote administration may not only result in the reduction of free or active toxin level, but also in the mitigation of end-organ effects of the toxin by mechanisms that include competitive inhibition, receptor blockade or direct antagonism of the toxin.

Mechanism of action of antidotes

Reduction in free toxin level can be achieved by specific and non-specific agents that bind to the toxin. The most commonly used non-specific binding agent is activated charcoal. Specific binders include chelating agents, bioscavenger therapy and immunotherapy. In some situations, enhanced elimination can be achieved by urinary alkalization or hemadsorption. Competitive inhibition of enzymes (e.g. ethanol for methanol poisoning), enhancement of enzyme function (e.g. oximes for organophosphorus poisoning) and competitive receptor blockade (e.g. naloxone, flumazenil) are other mechanisms by which antidotes act. Drugs such as N-acetyl cysteine and sodium thiocyanate reduce the formation of toxic metabolites in paracetamol and cyanide poisoning respectively. Drugs such as atropine and magnesium are used to counteract the end-organ effects in organophosphorus poisoning. Vitamins such as vitamin K, folic acid and pyridoxine are used to antagonise the effects of warfarin, methotrexate and INH respectively in the setting of toxicity or overdose. This review provides an overview of the role of antidotes in poisoning.

How to cite this article

Chacko B, Peter JV. Antidotes in Poisoning. Indian J Crit Care Med 2019;23(Suppl 4):S241-S249.

First aid interventions by laypeople for acute oral poisoning

BACKGROUND

Oral poisoning is a major cause of mortality and disability worldwide, with estimates of over 100,000 deaths due to unintentional poisoning each year and an overrepresentation of children below five years of age. Any effective intervention that laypeople can apply to limit or delay uptake or to evacuate, dilute or neutralize the poison before professional help arrives may limit toxicity and save lives.

OBJECTIVES

To assess the effects of pre-hospital interventions (alone or in combination) for treating acute oral poisoning, available to and feasible for laypeople before the arrival of professional help.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, CINAHL, ISI Web of Science, International Pharmaceutical Abstracts, and three clinical trials registries to 11 May 2017, and we also carried out reference checking and citation searching.

SELECTION CRITERIA

We included randomized controlled trials comparing interventions (alone or in combination) that are feasible in a pre-hospital setting for treating acute oral poisoning patients, including but potentially not limited to activated charcoal (AC), emetics, cathartics, diluents, neutralizing agents and body positioning.

DATA COLLECTION AND ANALYSIS

Two reviewers independently performed study selection, data collection and assessment. Primary outcomes of this review were incidence of mortality and adverse events, plus incidence and severity of symptoms of poisoning. Secondary outcomes were duration of symptoms of poisoning, drug absorption, and incidence of hospitalization and ICU admission.

MAIN RESULTS

We included 24 trials involving 7099 participants. Using the Cochrane 'Risk of bias' tool, we assessed no study as being at low risk of bias for all domains. Many studies were poorly reported, so the risk of selection and detection biases were often unclear. Most studies reported important outcomes incompletely, and we judged them to be at high risk of reporting bias.All but one study enrolled oral poisoning patients in an emergency department; the remaining study was conducted in a pre-hospital setting. Fourteen studies included multiple toxic syndromes or did not specify, while the other studies specifically investigated paracetamol (2 studies), carbamazepine (2 studies), tricyclic antidepressant (2 studies), yellow oleander (2 studies), benzodiazepine (1 study), or toxic berry intoxication (1 study). Eighteen trials investigated the effects of activated charcoal (AC), administered as a single dose (SDAC) or in multiple doses (MDAC), alone or in combination with other first aid interventions (a cathartic) and/or hospital treatments. Six studies investigated syrup of ipecac plus other first aid interventions (SDAC + cathartic) versus ipecac alone. The collected evidence was mostly of low to very low certainty, often downgraded for indirectness, risk of bias or imprecision due to low numbers of events.First aid interventions that limit or delay the absorption of the poison in the bodyWe are uncertain about the effect of SDAC compared to no intervention on the incidence of adverse events in general (zero events in both treatment groups; 1 study, 451 participants) or vomiting specifically (Peto odds ratio (OR) 4.17, 95% confidence interval (CI) 0.30 to 57.26, 1 study, 25 participants), ICU admission (Peto OR 7.77, 95% CI 0.15 to 391.93, 1 study, 451 participants) and clinical deterioration (zero events in both treatment groups; 1 study, 451 participants) in participants with mixed types or paracetamol poisoning, as all evidence for these outcomes was of very low certainty. No studies assessed SDAC for mortality, duration of symptoms, drug absorption or hospitalization.Only one study compared SDAC to syrup of ipecac in participants with mixed types of poisoning, providing very low-certainty evidence. Therefore we are uncertain about the effects on Glasgow Coma Scale scores (mean difference (MD) -0.15, 95% CI -0.43 to 0.13, 1 study, 34 participants) or incidence of adverse events (risk ratio (RR) 1.24, 95% CI 0.26 to 5.83, 1 study, 34 participants). No information was available concerning mortality, duration of symptoms, drug absorption, hospitalization or ICU admission.This review also considered the added value of SDAC or MDAC to hospital interventions, which mostly included gastric lavage. No included studies investigated the use of body positioning in oral poisoning patients.First aid interventions that evacuate the poison from the gastrointestinal tractWe found one study comparing ipecac versus no intervention in toxic berry ingestion in a pre-hospital setting. Low-certainty evidence suggests there may be an increase in the incidence of adverse events, but the study did not report incidence of mortality, incidence or duration of symptoms of poisoning, drug absorption, hospitalization or ICU admission (103 participants).In addition, we also considered the added value of syrup of ipecac to SDAC plus a cathartic and the added value of a cathartic to SDAC.No studies used cathartics as an individual intervention.First aid interventions that neutralize or dilute the poison No included studies investigated the neutralization or dilution of the poison in oral poisoning patients.The review also considered combinations of different first aid interventions.

AUTHORS' CONCLUSIONS

The studies included in this review provided mostly low- or very low-certainty evidence about the use of first aid interventions for acute oral poisoning. A key limitation was the fact that only one included study actually took place in a pre-hospital setting, which undermines our confidence in the applicability of these results to this setting. Thus, the amount of evidence collected was insufficient to draw any conclusions.

Racial disparities in the treatment of acute overdose in the emergency department

OBJECTIVES

Racial and ethnic disparities in the United States continue to exist in many disciplines of medicine, extending to care in the Emergency Department (ED). We sought to examine the relationship between patient race/ethnicity and use of either antidotal therapy or gastrointestinal decontamination for individuals presenting to the ED for acute drug overdose.

METHODS

We completed a secondary analysis of a prospective cohort of patients with suspected acute overdose presenting to two urban tertiary care hospitals between 2009 and 2014. Race was self-identified during ED registration. Antidote administration (primary outcome) and gastrointestinal decontamination (secondary outcome) were reviewed and verified via agreement between two board certified medical toxicologists. Associations between race and outcomes were analyzed using a logistic regression model.

RESULTS

We reviewed 3252 ED patients with acute overdose. Overall, 542 people were treated with an antidote and 234 cases were treated with activated charcoal, either single or multiple dose. Compared to Whites, Blacks and Hispanics were significantly less likely to receive any antidote. The analysis was underpowered to detect racial disparities in the administration of activated charcoal.

CONCLUSIONS

Blacks and Hispanics are significantly less likely to receive any antidote when presenting to the ED for acute drug overdose. Further studies are needed to determine national prevalence of this apparent disparity in care and to fully characterize how race plays a role in management of acute overdose.

Theophylline toxicity: An old poisoning for a new generation of physicians

A healthy 4-year-old female presented to the emergency department for vomiting and diarrhea. She was diagnosed with a urinary tract infection, treated with antibiotics and anti-emetics and discharged. Within four hours, her symptoms recurred, followed by decreasing responsiveness and seizures. She had significant hypokalemia, hyperglycemia, and a combined respiratory and metabolic acidosis. A sibling then mentioned that the patient ingested their father's 200 mg sustained-release theophylline tablets the previous morning. A serum theophylline level was immediately ordered and returned >444 μmol/L. The patient was intubated and treated with activated charcoal, antiemetics, potassium and intravenous fluids. She underwent continuous renal replacement therapy and her levels declined over the next 24 hours. She was extubated on hospital day 2 and discharged without sequelae. Theophylline ingestions are rare but potentially very serious. Physicians need to know how to diagnose and treat these ingestions.

Case Report of Aspirin Overdose: Bezoar Formation and Controversies of Multiple-Dose Activated Charcoal in Salicylate Poisoning

Bezoar formation is cited to be the cause of delayed absorption of aspirin in overdose of enteric-coated aspirin preparation. However, such phenomenon from oral overdose of regular aspirin preparation has not been clearly demonstrated in human. The use of multiple-dose activated charcoal (MDAC) in salicylate poisoning remains controversial. We report a case of regular-preparation salicylate poisoning with rebound of the serum salicylate level after discontinuation of MDAC administration. Bezoar formation as the underlying cause of the rebound and the effect of MDAC on serum salicylate level are discussed.

Which is the best in carbamazepine overdose?

Intravenous lipid emulsion treatment is safer, faster, and easier to apply and could be a powerful alternative to extracorporeal treatment methods in carbamazepine intoxication.

Valproic Acid Overdose Review of a Case With Electrocardiographic Changes

BACKGROUND

Valproic acid (VPA) is increasingly used to treat a variety of medical disorders, such as seizures, psychiatric disorders, and headaches. Therefore, accidental and intentional ingestions with valproic acid are increasing.

OBJECTIVES

A case is presented in an adolescent with ischemic electrocardiographic changes after an acute overdose with VPA.

DISCUSSION

Major features of a valproic acid overdose include respiratory depression, progressive coma, hepatotoxicity, thrombocytopenia, and hemodynamic instability. Electrocardiographic abnormalities usually consist of tachycardia and nonspecific changes. Supportive care is indicated in most overdoses and involves the monitoring and correction of electrolyte abnormalities, coagulopathies, and acid-base imbalances. Treatment may include activated charcoal, naloxone, l-carnitine, and extracorporeal detoxification.

CONCLUSIONS

Valproic acid overdose is a relatively rare and electrocardiographic changes usually consist of tachycardia and nonspecific changes, but ischemic changes may occur and usually transient and require only recognition.

International Variability in Gastrointestinal Decontamination With Acute Poisonings

BACKGROUND AND OBJECTIVES

Identifying international differences in the management of acute pediatric poisonings may help improve the quality of care. The objective of this study was to assess the international variation and appropriateness of gastrointestinal decontamination (GID) procedures performed in children and adolescents who present with acute poisonings to emergency departments.

METHODS

This was an international, multicenter, cross-sectional prospective study including children <18 years with poisoning exposures presenting to 105 emergency departments in 20 countries from 8 global regions belonging to the Pediatric Emergency Research Networks. Data collection started between January and September 2013 and continued for 1 year. The appropriateness of GID procedures performed was analyzed using the American Academy of Clinical Toxicology and the European Association of Poisons Centres and Clinical Toxicologists' recommendations. Multivariate logistic regression was performed to identify independent risk factors for performing GID procedures.

RESULTS

We included 1688 patients, 338 of whom (20.0%, 95% confidence interval 18.1%-22.0%) underwent the following GID procedures: activated charcoal (166, 49.1%), activated charcoal and gastric lavage (122, 36.1%), gastric lavage (47, 13.9%), and ipecac (3, 0.9%). In 155 (45.8%, 40.5%-51.2%), the GID procedure was considered appropriate, with significant differences between regions. Independent risk factors for GID procedures included age, toxin category, mechanism of poisoning, absence of symptoms, and the region where the intoxication occurred (P < .001).

CONCLUSIONS

Globally, there are substantial differences in the use and appropriateness of GID procedures in the management of pediatric poisonings. International best practices need to be better implemented.

Clinical characteristics of patients who overdose on multiple psychotropic drugs in Tokyo

OBJECTIVE

The purpose of this study was to identify the clinical aspects leading to overdose of multiple psychotropic drugs, in order to determine areas which need attention in the proper treatment of overdose patients.

METHODS

Patients who were treated for overdose of psychotropic drugs at our emergency and critical center over two years were targeted. The clinical data was gathered from the medical records and database of all patients, including age, gender, vital signs, and laboratory data, drugs, and medical complications during hospital stay. In addition primary patient care at the emergency department was examined.

RESULTS

Among the 277 patients treated during this study period, 255 (74.0%) used two or more types of psychotropic drugs. Risk factors associated with endotracheal intubation and aspiration pneumonitis included the use of antipsychotics and/or barbiturates as types of overdose drugs. The mean number of days in the ICU was 3.4 days. Seventy-four patients (26.7%) stayed 4 days or more in the ICU of which 16 patients (5.8%) still had suicidal thoughts. A significantly higher incidence of extended ICU stay or endotracheal intubation and aspiration pneumonitis was observed in the group who overdosed on more than 50 or 60 tablets of psychotropic drugs, respectively.

CONCLUSIONS

Patients who ingested an overdose of more than 60 tablets of psychotropic drugs should be considered a high-risk group requiring intensive care with extended ICU stay. In case of including antipsychotics and/or barbiturates, the patient should be observed carefully due to a higher risk of medical complications.

Antidote availability in the municipality of Campinas, São Paulo, Brazil

CONTEXT AND OBJECTIVE:

The lack of availability of antidotes in emergency services is a worldwide concern. The aim of the present study was to evaluate the availability of antidotes used for treating poisoning in Campinas (SP).

DESIGN AND SETTING:

This was a cross-sectional study of emergency services in Campinas, conducted in 2010-2012.

METHODS:

The availability, amount in stock, place of storage and access time for 26 antidotal treatments was investigated. In the hospitals, the availability of at least one complete treatment for a 70 kg adult over the first 24 hours of admission was evaluated based on stock and access recommendations contained in two international guidelines.

RESULTS:

14 out of 17 functioning emergency services participated in the study, comprising pre-hospital services such as the public emergency ambulance service (SAMU; n = 1) and public emergency rooms for admissions lasting ≤ 24 hours (UPAs; n = 3), and 10 hospitals with emergency services. Six antidotes (atropine, sodium bicarbonate, diazepam, Phytomenadione, flumazenil and calcium gluconate) were stocked in all the services, followed by 13 units that also stocked activated charcoal, naloxone and diphenhydramine or biperiden. No service stocked all of the recommended antidotes; only the regional Poison Control Center had stocks close to recommended (22/26 antidotal treatments). The 10 hospitals had almost half of the antidotes for starting treatments, but only one quarter of the antidotes was present with stocks sufficient for providing treatment for 24 hours.

CONCLUSION:

The stock of antidotes for attending poisoning emergencies in the municipality of Campinas is incomplete and needs to be improved.

Extracorporeal treatments in a dapsone overdose: a case report

INTRODUCTION

Intentional dapsone intoxication can be life-threatening. There is limited data on the clinical effect of extracorporeal treatments (ECTRs) on dapsone elimination. We describe a case of severe dapsone toxicity treated with different ECTRs.

CASE DETAILS

A 23-year-old woman was admitted 2.5 h after ingesting 2.2 g of dapsone. She developed methemoglobinemia (39.9%) and showed signs of toxicity (hemodynamic instability and altered mental status) despite multiple-activated charcoal, methylene blue, vasopressors and endotracheal intubation. Continuous venovenous hemofiltration (CVVH) was then initiated for 5 h, followed by intermittent hemodialysis with hemoperfusion (IHD-HP) for 4 h, and CVVH for another 48 h. The platelet count decreased to 32 × 10⁹/L 3 h after IHD-HP. The elimination half-life of dapsone was 2.0 h during IHD-HP, and 14.2 h during CVVH. Mean dapsone clearance with IHD was 62 mL/min versus 22 mL/min with CVVH. IHD removed 95.3 mg, and CVVH removed 67.8 mg over 3.8 h. No rebound occurred following ECTR cessation. The toxicokinetics of dapsone metabolites were also accelerated during ECTR. The patient was extubated after 3.5 days and discharged without sequelae after 7 days.

DISCUSSION

Dapsone clearance was enhanced by ECTR, especially by IHD-HP. However, HP was associated with severe asymptomatic thrombocytopenia.

Nonsteroidal Anti-Inflammatory Drug Toxicity in Children: A Clinical Review

Nonsteroidal anti-inflammatory drugs (NSAIDs) are one of the most widely used classes of medications in children. Despite a reported positive safety profile, NSAIDs have been associated with toxicities in both overdose and routine use. Most children with NSAID overdoses are asymptomatic and should be managed conservatively, whereas a small number may present with severe symptoms. We review NSAID exposures in children and strategies for their clinical evaluation and management.

Extracorporeal Treatment in Phenytoin Poisoning: Systematic Review and Recommendations from the EXTRIP (Extracorporeal Treatments in Poisoning) Workgroup

The Extracorporeal Treatments in Poisoning (EXTRIP) Workgroup conducted a systematic literature review using a standardized process to develop evidence-based recommendations on the use of extracorporeal treatment (ECTR) in patients with phenytoin poisoning. The authors reviewed all articles, extracted data, summarized findings, and proposed structured voting statements following a predetermined format. A 2-round modified Delphi method was used to reach a consensus on voting statements, and the RAND/UCLA Appropriateness Method was used to quantify disagreement. 51 articles met the inclusion criteria. Only case reports, case series, and pharmacokinetic studies were identified, yielding a very low quality of evidence. Clinical data from 31 patients and toxicokinetic grading from 46 patients were abstracted. The workgroup concluded that phenytoin is moderately dialyzable (level of evidence = C) despite its high protein binding and made the following recommendations. ECTR would be reasonable in select cases of severe phenytoin poisoning (neutral recommendation, 3D). ECTR is suggested if prolonged coma is present or expected (graded 2D) and it would be reasonable if prolonged incapacitating ataxia is present or expected (graded 3D). If ECTR is used, it should be discontinued when clinical improvement is apparent (graded 1D). The preferred ECTR modality in phenytoin poisoning is intermittent hemodialysis (graded 1D), but hemoperfusion is an acceptable alternative if hemodialysis is not available (graded 1D). In summary, phenytoin appears to be amenable to extracorporeal removal. However, because of the low incidence of irreversible tissue injury or death related to phenytoin poisoning and the relatively limited effect of ECTR on phenytoin removal, the workgroup proposed the use of ECTR only in very select patients with severe phenytoin poisoning.

Activated charcoal for acute overdose: a reappraisal

Sometimes mistakenly characterized as a 'universal antidote,' activated charcoal (AC) is the most frequently employed method of gastrointestinal decontamination in the developed world. Typically administered as a single dose (SDAC), its tremendous surface area permits the binding of many drugs and toxins in the gastrointestinal lumen, reducing their systemic absorption. Like other decontamination procedures, the utility of SDAC attenuates with time, and, although generally safe, it is not free of risk. A large body of evidence demonstrates that SDAC can reduce the absorption of drugs and xenobiotics but most such studies involve volunteers and have little generalizability to clinical practice. Few rigorous clinical trials of SDAC have been conducted, and none validate or refute its utility in those patients who are intuitively most likely to benefit. Over the past decade, a growing body of observational data have demonstrated that SDAC can elicit substantial reductions in drug absorption in acutely poisoned patients. The challenge for clinicians rests in differentiating those patients most likely to benefit from SDAC from those in whom meaningful improvement is doubtful. This is often a difficult determination not well suited to an algorithmic approach. The present narrative review summarizes the data supporting the benefits and harms of SDAC, and offers pragmatic suggestions for clinical practice.

A Review of the Toxicologic Implications of Obesity

The increasing prevalence of obesity in developed nations has far-reaching implications for medical toxicology. The management of obese patients is complicated by comorbid illnesses, changes in cardiovascular and respiratory physiology, alterations in pharmacokinetics, and a lack of studies to identify appropriate dosing for current therapeutics and antidotes. In this review article, we examine obesity-associated physiologic and pharmacokinetic changes that may increase the vulnerability of obese patients to overdose. Further research is needed to characterize the relationship between drug toxicity and obesity.

Developments in extracorporeal therapy for the poisoned patient

The modern use of extracorporeal therapies to treat poisoning and drug overdoses dates back to the early 20th century and has evolved along with their use as treatment for acute kidney injury or as maintenance therapy in advanced kidney disease. As our understanding of drug pharmacokinetics and membrane materials has increased, the technologies of extracorporeal therapy and their applications have become more sophisticated. Despite that, there is little robust evidence to guide clinicians on the optimal use of extracorporeal therapy in treating poisoning beyond case reports and series. New efforts are underway to remedy that: the Extracorporeal Treatments in Poisoning Workgroup (EXTRIP) is an international effort on the part of nephrologists, pharmacists and toxicologists to review the available data and formulate evidence-based guidelines on how to use extracorporeal techniques to treat poisoning and improve patient outcomes. Meanwhile, new techniques and membranes are under development. This review will summarize those key scientific and technologic developments, the efforts to optimize their use and new directions in research.

Extracorporeal treatment for valproic acid poisoning: systematic review and recommendations from the EXTRIP workgroup

BACKGROUND

The EXtracorporeal TReatments In Poisoning (EXTRIP) workgroup presents its systematic review and clinical recommendations on the use of extracorporeal treatment (ECTR) in valproic acid (VPA) poisoning.

METHODS

The lead authors reviewed all of the articles from a systematic literature search, extracted the data, summarized the key findings, and proposed structured voting statements following a predetermined format. A two-round modified Delphi method was chosen to reach a consensus on voting statements and the RAND/UCLA Appropriateness Method was used to quantify disagreement. Anonymous votes were compiled, returned, and discussed in person. A second vote was conducted to determine the final workgroup recommendations.

RESULTS

The latest literature search conducted in November 2014 retrieved a total of 79 articles for final qualitative analysis, including one observational study, one uncontrolled cohort study with aggregate analysis, 70 case reports and case series, and 7 pharmacokinetic studies, yielding a very low quality of evidence for all recommendations. Clinical data were reported for 82 overdose patients while pharmaco/toxicokinetic grading was performed in 55 patients. The workgroup concluded that VPA is moderately dialyzable (level of evidence = B) and made the following recommendations: ECTR is recommended in severe VPA poisoning (1D); recommendations for ECTR include a VPA concentration > 1300 mg/L (9000 μmol/L)(1D), the presence of cerebral edema (1D) or shock (1D); suggestions for ECTR include a VPA concentration > 900 mg/L (6250 μmol/L)(2D), coma or respiratory depression requiring mechanical ventilation (2D), acute hyperammonemia (2D), or pH ≤ 7.10 (2D). Cessation of ECTR is indicated when clinical improvement is apparent (1D) or the serum VPA concentration is between 50 and 100 mg/L (350-700 μmol/L)(2D). Intermittent hemodialysis is the preferred ECTR in VPA poisoning (1D). If hemodialysis is not available, then intermittent hemoperfusion (1D) or continuous renal replacement therapy (2D) is an acceptable alternative.

CONCLUSIONS

VPA is moderately dialyzable in the setting of overdose. ECTR is indicated for VPA poisoning if at least one of the above criteria is present. Intermittent hemodialysis is the preferred ECTR modality in VPA poisoning.

Effect of sorbitol, single, and multidose activated charcoal administration on carprofen absorption following experimental overdose in dogs

OBJECTIVE

To compare the effectiveness of single dose activated charcoal, single dose activated charcoal with sorbitol, and multidose activated charcoal in reducing plasma carprofen concentrations following experimental overdose in dogs.

DESIGN

Randomized, four period cross-over study.

SETTING

University research setting.

ANIMALS

Eight healthy Beagles.

INTERVENTIONS

A 120 mg/kg of carprofen was administered orally to each dog followed by either (i) a single 2 g/kg activated charcoal administration 1 hour following carprofen ingestion (AC); (ii) 2 g/kg activated charcoal with 3.84 g/kg sorbitol 1 hour following carprofen ingestion (ACS); (iii) 2 g/kg activated charcoal 1 hour after carprofen ingestion and repeated every 6 hours for a total of 4 doses (MD); (iv) no treatment (control).

MEASUREMENTS AND MAIN RESULTS

Plasma carprofen concentrations were obtained over a 36-hour period following carprofen ingestion for each protocol. Pharmacokinetic modeling was performed and time versus concentration, area under the curve, maximum plasma concentration, time to maximum concentration, and elimination half-life were calculated and compared among the groups using ANOVA followed by Tukey's multiple comparisons test. Activated charcoal, activated charcoal with sorbitol (ACS), and multiple-dose activated charcoal (MD) significantly reduced the area under the curve compared to the control group. AC and MD significantly reduced the maximum concentration when compared to the control group. MD significantly reduced elimination half-life when compared to ACS and the control group. There were no other significant differences among the treatment groups.

CONCLUSIONS

Activated charcoal and ACS are as effective as MD in reducing serum carprofen concentrations following experimental overdose in dogs. Prospective studies are warranted to evaluate the effectiveness of AC, ACS, and MD in the clinical setting.

Extracorporeal treatment for theophylline poisoning: systematic review and recommendations from the EXTRIP workgroup

BACKGROUND

The Extracorporeal Treatments in Poisoning workgroup was created to provide evidence-based recommendations on the use of extracorporeal treatments (ECTRs) in poisoning. Here, the workgroup presents its systematic review and recommendations for theophylline.

METHODS

After a systematic review of the literature, a subgroup reviewed articles, extracted data, summarized findings, and proposed structured voting statements following a pre-determined format. A two-round modified Delphi method was chosen to reach a consensus on voting statements and the RAND/UCLA Appropriateness Method was used to quantify disagreement. Anonymous votes were compiled, returned, and discussed. A second vote determined the final recommendations.

RESULTS

141 articles were included: 6 in vitro studies, 4 animal studies, 101 case reports/case series, 7 descriptive cohorts, 4 observational studies, and 19 pharmacokinetic studies, yielding a low-to-very-low quality of evidence for all recommendations. Data on 143 patients were reviewed, including 10 deaths. The workgroup concluded that theophylline is dialyzable (level of evidence = A) and made the following recommendations: ECTR is recommended in severe theophylline poisoning (1C). Specific recommendations for ECTR include a theophylline concentration [theophylline] > 100 mg/L (555 μmol/L) in acute exposure (1C), the presence of seizures (1D), life-threatening dysrhythmias (1D) or shock (1D), a rising [theophylline] despite optimal therapy (1D), and clinical deterioration despite optimal care (1D). In chronic poisoning, ECTR is suggested if [theophylline] > 60 mg/L (333 μmol/L) (2D) or if the [theophylline] > 50 mg/L (278 μmol/L) and the patient is either less than 6 months of age or older than 60 years of age (2D). ECTR is also suggested if gastrointestinal decontamination cannot be administered (2D). ECTR should be continued until clinical improvement is apparent or the [theophylline] is < 15 mg/L (83 μmol/L) (1D). Following the cessation of ECTR, patients should be closely monitored. Intermittent hemodialysis is the preferred method of ECTR (1C). If intermittent hemodialysis is unavailable, hemoperfusion (1C) or continuous renal replacement therapies may be considered (3D). Exchange transfusion is an adequate alternative to hemodialysis in neonates (2D). Multi-dose activated charcoal should be continued during ECTR (1D).

CONCLUSION

Theophylline poisoning is amenable to ECTRs. The workgroup recommended extracorporeal removal in the case of severe theophylline poisoning.

Coma After Quetiapine Fumarate Intentional Overdose in a 71-year-old Man: A Case Report

A 71-year-old man developed coma with severe respiratory failure, hypotension, and tachycardia induced by the intentional ingestion of quetiapine fumarate extended release (XR) 20 g. At the time, he had been treated for bipolar depression with venlafaxine 75 mg/day, lamotrigine 100 mg/day, pregabalin 75 mg/day, and quetiapine XR 400 mg/day for approximately 1 year. Comorbidities were hypertension treated with metoprolol, diabetes mellitus type 2 treated with metformin, and benign prostatic hyperplasia treated with silodosin. In the emergency room, about 4 h after ingestion of quetiapine fumarate XR, the presenting symptomatology was characterized by coma (Glasgow Coma Scale score 3), hypotension (blood pressure [BP] 90/60 mmHg), tachycardia (electrocardiogram [ECG] showed sinus tachycardia with heart rate 120 beats per minute and a QTc of 499 ms). A gastric lavage was performed and activated charcoal 50 g and magnesium sulfate 30 g was administered. About 6 h after ingestion, he developed marked desaturation and underwent mechanical ventilation; 13 h after ingestion, a severe hypotensive episode followed (BP 70/40), which was treated with an infusion of ringer lactate 500 cc. On the 3rd day after intentional overdose, an episode of agitation occurred; 4 days after ingestion, the quetiapine plasma level was found to be 42 ng/ml (within therapeutic range). At 5 days after ingestion, the patient developed septicemia caused by staphylococci (probably originating from the central vein catheter), which was treated with antibiotic therapy. On days 10 and 18 after the suicide attempt, two episodes of paroxysmal supraventricular tachycardia (PSVT) occurred and were successfully treated with intravenous adenosine triphosphate. The patient recovered completely without residual symptoms. In line with literature data, in this case report, symptoms of quetiapine overdose were tachycardia, agitation, hypotension, QT interval prolongation, and coma. A causal relationship between PSVT and quetiapine intoxication seems quite unlikely due to the drug level.

Safety concerns in simultaneous use of prescription and 'over-the-counter' medicines- results of patient survey in Estonia

During the last decades, the share of population using prescription (Rx) medicines has considerably increased. With the wider introduction of self-medication and the use of over-the-counter (OTC) medicines, there is a real threat for drug-drug interactions between Rx and OTC medicines neither identified nor overseen by healthcare specialists.

The objectives of this survey were to ascertain how often, and for what conditions OTC and Rx medicines are used simultaneously, and to discuss possible health hazards connected with the concomitant use of these medicines.

This survey was designed as a descriptive, cross-sectional questionnaire-based interview which was conducted amongst pharmacy customers and patients in urban and rural areas of Estonia in between 2010–2012.

In total, 712 respondents participated in the survey. Of those, 50.4% reported concomitant use of Rx and OTC medicines during the survey. The simultaneous use of Rx and OTC medicines increased with age and the number of chronic diseases (both p < 0.001). Of chronic patients, 37.1% used Rx and OTC medicines on a daily basis over a four-week period before the survey, and considering reported chronic diseases and the most widespread OTC medicines, they could encounter drug-drug interactions between Rx medicines (e.g. antihypertensives, anti-inflammatory medicines) and OTC medicines (e.g. paracetamol, NSAID-s, herbal medicines and adsorbents).

The present survey revealed frequent concomitant use of Rx and OTC medicines. Especially vulnerable are chronic and elderly patients. In the future, both patients and healthcare specialists should pay more attention to possible drug-drug interactions of Rx and OTC medicines.