Overview of Toxic Ingestions in Adolescents.

There has been an overall increase in the number of suspected suicide attempts by self-poisoning among the adolescent population. Incidences of self-poisoning have increased since the coronavirus 2019 pandemic, particularly among patients age 10 to 19 years. Common agents used in self-poisoning include over-the-counter and prescription medications. It is crucial to identify adolescent patients with risk factors and provide appropriate resources to reduce the likelihood of intentional toxic ingestion. This article aims to summarize the current state of intentional toxic ingestions by adolescents, provide an overview of the most common agents implicated in self-poisoning, and discuss the best practices in screening patients. [Pediatr Ann. 2024;53(9):e330-e336.].

Drug Decriminalization, Fentanyl, and Fatal Overdoses in Oregon.

Importance: With the implementation of Measure 110 (M110) in 2021, Oregon became the first US state to decriminalize small amounts of any drug for personal use. To date, no analysis of the association of this law with overdose mortality has fully accounted for the introduction of fentanyl-a substance that is known to drive fatal overdose-to Oregon's unregulated drug market. Objective: To evaluate whether the decriminalization of drug possession in Oregon was associated with changes in fatal drug overdose rates after accounting for the rapid spread of fentanyl in Oregon's unregulated drug market. Design, Setting, and Participants: In this cohort study, the association between fatal overdose and enactment of M110 was analyzed using a matrix completion synthetic control method. The control group consisted of the 48 US states and Washington, DC, all of which did not decriminalize drugs. The rapid spread of fentanyl in unregulated drug markets was determined using the state-level percentage of all samples reported to the National Forensic Laboratory Information System that were identified as fentanyl or its analogues. Mortality data were obtained from the Centers for Disease Control and Prevention for January 1, 2008, to December 31, 2022. Data analysis was performed from fall 2023 through spring 2024. Exposures: Measure 110 took effect in Oregon on February 1, 2021. Main Outcomes and Measures: The primary outcome assessed was fatal drug overdose rates per half-year. A changepoint analysis also determined when each state experienced a rapid escalation of fentanyl in its unregulated drug market. Results: In this analysis, rapid spread of fentanyl in Oregon's unregulated drug supply occurred in the first half of 2021, contemporaneous with enactment of M110. A positive crude association was found between drug decriminalization and fatal overdose rate per 100 000 per half year (estimate [SE], 1.83 [0.47]; P < .001). After adjusting for the spread of fentanyl as a confounder, the effect size changed signs (estimate [SE], -0.51 [0.61]; P = .41) and there was no longer an association between decriminalization and overdose mortality in Oregon. Sensitivity analyses were consistent with this result. Conclusions and Relevance: In this cohort study of fatal drug overdose and the spread of fentanyl through Oregon's unregulated drug market, no association between M110 and fatal overdose rates was observed. Future evaluations of the health effects of drug policies should account for changes in the composition of unregulated drug markets.

Evaluating fentanyl test strips as a harm reduction strategy in rural and urban counties: study protocol for a randomized controlled trial.

BACKGROUND: Opioid-related fatalities are a leading cause of death in Ohio and nationally, with an increasing number of overdoses attributable to fentanyl. Rapid fentanyl test strips can identify fentanyl and some fentanyl analogs in urine samples and are increasingly being used to check illicit drugs for fentanyl before they are used. Fentanyl test strips are a promising harm reduction strategy; however, little is known about the real-world acceptability and impact of fentanyl test strip use. This study investigates fentanyl test strip distribution and education as a harm reduction strategy to prevent overdoses among people who use drugs. METHODS: The research team will recruit 2400 individuals ≥ 18 years with self-reported use of illicit drugs or drugs purchased on the street within the past 6 months. Recruitment will occur at opioid overdose education and naloxone distribution programs in 16 urban and 12 rural Ohio counties. Participating sites will be randomized at the county level to the intervention or non-intervention study arm. A brief fentanyl test strip educational intervention and fentanyl test strips will be provided to participants recruited from sites in the intervention arm. These participants will be eligible to receive additional fentanyl test strips for 2 years post-enrollment. Participants recruited from sites in the non-intervention arm will not receive fentanyl test strip education or fentanyl test strips. All participants will be followed for 2 years post-enrollment using biweekly, quarterly, and 6-month surveys. Primary outcomes include (1) identification of perceived barriers and facilitating factors associated with incorporating fentanyl test strip education and distribution into opioid overdose education and naloxone distribution programs; (2) differences in knowledge and self-efficacy regarding how to test drugs for fentanyl and strategies for reducing overdose risk between the intervention and non-intervention groups; and (3) differences in non-fatal and fatal overdose rates between the intervention and non-intervention groups. DISCUSSION: Findings from this cluster randomized controlled trial will contribute valuable information about the feasibility, acceptability, and impact of integrating fentanyl test strip drug checking in rural and urban communities in Ohio and help guide future overdose prevention interventions. TRIAL REGISTRATION: ClinicalTrials.gov NCT05463341. Registered on July 19, 2022. https://clinicaltrials.gov/study/NCT05463341.

State Mandates On Naloxone Coprescribing Associated With Short-Term Increase In Naloxone Codispensing.

In the midst of the opioid crisis in the US, efforts to mitigate overdose risks have become paramount, leading some states to introduce mandates for coprescribing the life-saving overdose reversal drug naloxone. These mandates were designed to specifically address people receiving opioid analgesics who had an elevated risk for overdose. This included people receiving high opioid dosages, those concurrently using benzodiazepines, or those with a history of substance use disorder or overdose. Using a nationally representative, multipayer cohort of patients receiving prescription opioids, we investigated how naloxone codispensing rates changed at the state level from 2016 to 2021 among patients with an elevated risk for overdose. Then we used controlled interrupted time series analyses to assess mandates' longitudinal impact on naloxone codispensing in ten states that implemented mandates. We observed an immediate and significant increase in the naloxone codispensing rates in eight states after the implementation of mandates. Nevertheless, in five of these states, the codispensing rates exhibited a subsequent downward trend after the initial increase. State mandates show potential for improving naloxone codispensing; however, mandates alone might not be adequate for sustained change. Further research is needed to identify strategies complementing and enhancing the impact of mandates in combating the overdose crisis.

Benefits and challenges of geographic information systems (GIS) for data-driven outreach in black communities experiencing overdose disparities: results of a stakeholder focus group.

BACKGROUND: Black individuals in the U.S. face increasing racial disparities in drug overdose related to social determinants of health, including place-based features. Mobile outreach efforts work to mitigate social determinants by servicing geographic areas with low drug treatment and overdose prevention access but are often limited by convenience-based targets. Geographic information systems (GIS) are often used to characterize and visualize the overdose crisis and could be translated to community to guide mobile outreach services. The current study examines the initial acceptability and appropriateness of GIS to facilitate data-driven outreach for reducing overdose inequities facing Black individuals. METHODS: We convened a focus group of stakeholders (N = 8) in leadership roles at organizations conducting mobile outreach in predominantly Black neighborhoods of St. Louis, MO. Organizations represented provided adult mental health and substance use treatment or harm reduction services. Participants were prompted to discuss current outreach strategies and provided feedback on preliminary GIS-derived maps displaying regional overdose epidemiology. A reflexive approach to thematic analysis was used to extract themes. RESULTS: Four themes were identified that contextualize the acceptability and utility of an overdose visualization tool to mobile service providers in Black communities. They were: 1) importance of considering broader community context; 2) potential for awareness, engagement, and community collaboration; 3) ensuring data relevance to the affected community; and 4) data manipulation and validity concerns. CONCLUSIONS: There are several perceived benefits of using GIS to map overdose among mobile providers serving Black communities that are overburdened by the overdose crisis but under resourced. Perceived potential benefits included informing location-based targets for services as well as improving awareness of the overdose crisis and facilitating collaboration, advocacy, and resource allocation. However, as GIS-enabled visualization of drug overdose grows in science, public health, and community settings, stakeholders must consider concerns undermining community trust and benefits, particularly for Black communities facing historical inequities and ongoing disparities.

Minimal effects after a massive intravenous terbutaline overdose in a child.

A 22-kg female in early childhood with a history of reactive airway disease presented to a paediatric emergency department with acute shortness of breath, tachypnoea and wheezing. Despite treatment with albuterol and corticosteroids, her bronchospasm persisted, prompting the administration of terbutaline. The patient received 220 mcg (10 mcg/kg) terbutaline intravenously, followed immediately by an inadvertent supratherapeutic intravenous dose of 10 000 mcg (454.5 mcg/kg). The patient's laboratory results obtained minutes after the medication error were notable for: potassium, 3.1 mmol/L, lactate, 2.6 mmol/L and troponin I, 0.30 ng/mL (normal <0.03 ng/mL). Over the next 48 hours, serial serum troponin values decreased. The patient was discharged home approximately 72 hours after the initial presentation and she remained well based on follow-up calls over the next several months. Given the timing and trend of troponin concentrations, we do not believe the terbutaline overdose to be responsible for the myocardial injury.

Harm Reduction and Treatment Among People at High Risk of Overdose.

Importance: Rates of overdose deaths involving synthetic opioids remain high, increasingly involve stimulants combined with opioids, and are increasing rapidly in racially and ethnically minoritized communities, yet little is known about access to harm reduction and treatment services in these groups. Objective: To characterize access and barriers to harm reduction and treatment in a racially and ethnically diverse population of people who use drugs. Design, Setting, and Participants: A cross-sectional telephone survey of people recruited from 39 treatment, harm reduction, and social service organizations in Milwaukee County, Wisconsin; Flint and Detroit, Michigan; and statewide in New Jersey was conducted from January 30 to July 28, 2023. Adults who used cocaine, methamphetamine, or opioids in the past 30 days called a study hotline and completed an interview in English or Spanish. Exposures: Overdose experience, drug types used (opioids only, stimulants only, and polysubstance), and social risk factors (eg, financial instability and criminal legal involvement). Main Outcomes and Measures: Recent use of any harm reduction services, fentanyl test strips, naloxone possession, treatment, and self-reported barriers to services. Results: Of the total sample of 1240 adults, 486 (39.2%) were Black non-Hispanic, 183 (14.8%) were Hispanic, and 464 (37.4%) were White non-Hispanic. In the past 30 days, 826 individuals (66.6%) were polysubstance users, 135 (10.9%) used only opioids, and 279 (22.5%) used only stimulants. A total of 349 respondents (28.1%) experienced a prior-year overdose. Compared with those without a prior-year overdose, people with overdose were more likely to possess naloxone (80.7% vs 68.2%; P < .001), possess fentanyl test strips (36.8% vs 23.5%; P < .001), and use harm reduction services (63.4% vs 53.0%; P = .003), while differences in treatment use were nonsignificant (52.0% vs 46.6%; P = .24). Among stimulant-only users, 51.4% possessed naloxone compared with 77.3% of opioid-only users (P < .001) and 77.6% of polysubstance users (P < .001), with similar disparities in fentanyl test strip possession. Conclusions and Relevance: In this cross-sectional study of people who used drugs in the past 30 days, findings highlighted low use of harm reduction and treatment services among people who use stimulants. Additional communication regarding their importance may help increase the use of the services amidst a rapidly changing drug supply.

A quantitative LC-MS/MS method for investigation of polysubstance use involving heroin and cocaine.

Concurrent use of heroin and cocaine (known as the "speedball") prevails among substance use disorder populations, especially in opioid-dependent individuals, with severe consequences and a high fatality rate. Little is known about the patterns and correlations of the concurrent use of heroin and cocaine. It is vital to investigate such a polydrug use in both humans and animals to uncover concomitant toxicity and the cause of fatal overdose (death). In this study, we aimed to shed some light on the role of cocaine in the etiology of heroin-related deaths in the context of molecular pharmacokinetics (PK). For the purpose, a high-performance liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) method for simultaneous determination of heroin, cocaine, and their metabolites in whole blood was developed and fully validated in accordance with the US Food and Drug Administration (FDA) and European Medicines Agency (EMA) guidelines. Then, this method was used to analyze heroin, cocaine, and their metabolites in blood from the rats intraperitoneally administered non-lethal 10 mg/kg heroin or 20 mg/kg cocaine alone, or their combination that is lethal with a proximal mortality of 33 %. The obtained results from the rats that experienced the lethal toxicity revealed that the concurrent use of heroin and cocaine significantly increased the risk of fatality from overdose. Heroin significantly slowed down the elimination of cocaine and its main metabolites in blood, while cocaine significantly enhanced heroin metabolism from 6-monoacetylmorphine (6-MAM) to morphine. Similar elimination half-lives for other heroin metabolites were observed. These findings are reported for the first time in this study, facilitating our understanding of the polysubstance metabolism and severe consequences produced by the polydrug use.

Increases in housing rules and surveillance during COVID-19: impacts on overdose and overdose response in a community-based cohort of sex workers who use drugs in Vancouver, BC.

INTRODUCTION: Since the beginning of the COVID-19 pandemic, COVID-19 risk mitigation measures have expanded to include increased rules and surveillance in supportive housing. Yet, in the context of the dual public health emergencies of COVID-19 and the unregulated drug toxicity crisis, we have not evaluated the unintended health and social consequences of such measures, especially on criminalized women. In order to address this dearth of evidence, our aim was to assess the association between increased housing rules and surveillance during COVID-19 and (a) nonfatal overdose, and (b) administration of naloxone for overdose reversal among women sex workers who use drugs in Vancouver, BC. METHODS: This study is nested within An Evaluation of Sex Workers Health Access (AESHA), a community-based prospective cohort of women sex workers in Metro Vancouver (2010-present). Using cross-sectional data collected during the first year of COVID-19 (April 2020-2021), we developed separate multivariable logistic regression confounder models to examine the independent associations between experiencing increased housing rules and surveillance during COVID-19 on (a) nonfatal overdose, and (b) administration of naloxone for overdose reversal in the last 6 months. RESULTS: Amongst 166 participants, 10.8% reported experiencing a recent non-fatal overdose and 31.3% recently administered naloxone for overdose reversal. 56.6% reported experiencing increased rules and surveillance within their housing during COVID-19. The prevalence of non-fatal overdose and administering naloxone was significantly elevated among those exposed to increased housing rules and surveillance during COVID-19 versus those who were unexposed (83.3% vs. 52.1%; 75.0% vs. 48.2%, respectively). In separate multivariate confounder models, exposure to increased housing rules and surveillance during COVID-19 was independently associated with increased odds of administering naloxone [AOR: 3.66, CI: 1.63-8.21], and marginally associated with non-fatal overdose [AOR: 3.49, CI: 0.92-13.27]. CONCLUSION: Efforts to prioritize the right to safe, adequate and affordable housing must avoid reinforcing an overly coercive reliance on surveillance measures which, while often well-intended, can negatively shape residents' well-being. Furthermore, public health responses to pandemics must include criminalized populations so that measures do not exacerbate overdose risk. Implementation of a regulated drug supply is recommended, alongside housing policies that promote residents' rights, safety, and health.

An individual-based dynamic model to assess interventions to mitigate opioid overdose risk.

BACKGROUND: Illicit opioid overdose continues to rise in North America and is a leading cause of death. Mathematical modeling is a valuable tool to investigate the epidemiology of this public health issue, as it can characterize key features of population outcomes and quantify the broader effect of structural and interventional changes on overdose mortality. The aim of this study is to quantify and predict the impact of key harm reduction strategies at differing levels of scale-up on fatal and nonfatal overdose among a population of people engaging in unregulated opioid use in Toronto. METHODS: An individual-based model for opioid overdose was built featuring demographic and behavioural variation among members of the population. Key individual attributes known to scale the risk of fatal and nonfatal overdose were identified and incorporated into a dynamic modeling framework, wherein every member of the simulated population encompasses a set of distinct characteristics that govern demographics, intervention usage, and overdose incidence. The model was parametrized to fatal and nonfatal overdose events reported in Toronto in 2019. The interventions considered were opioid agonist therapy (OAT), supervised consumption sites (SCS), take-home naloxone (THN), drug-checking, and reducing fentanyl in the drug supply. Harm reduction scenarios were explored relative to a baseline model to examine the impact of each intervention being scaled from 0% use to 100% use on overdose events. RESULTS: Model simulations resulted in 3690.6 nonfatal and 295.4 fatal overdoses, coinciding with 2019 data from Toronto. From this baseline, at full scale-up, 290 deaths were averted by THN, 248 from eliminating fentanyl from the drug supply, 124 from SCS use, 173 from OAT, and 100 by drug-checking services. Drug-checking and reducing fentanyl in the drug supply were the only harm reduction strategies that reduced the number of nonfatal overdoses. CONCLUSIONS: Within a multi-faceted harm reduction approach, scaling up take-home naloxone, and reducing fentanyl in the drug supply led to the largest reduction in opioid overdose fatality in Toronto. Detailed model simulation studies provide an additional tool to assess and inform public health policy on harm reduction.

Fentanyl harm reduction strategies among Latinx communities in the United States: a scoping review.

PURPOSE: Fueled by the prescription opioid overdose crisis and increased influx of illicitly manufactured fentanyl, fentanyl overdoses continue to be a public health crisis that has cost the US economy over $1 trillion in reduced productivity, health care, family assistance, criminal justice, and accounted for over 74,000 deaths in 2023. A recent demographic shift in the opioid crisis has led to a rise in overdose deaths among the Latinx population. Harm reduction interventions, including the use of naloxone and fentanyl test strips, have been shown to be effective measures at reducing the number of opioid overdose deaths. The aim of this scoping review is to summarize naloxone and fentanyl test strip interventions and public health policies targeted to Latinx communities. METHODS: PubMed, CINHAL, Web of Science, Embase, and PsycINFO research databases using the keywords "fentanyl," "Latinx," "Harm Reduction," "Naloxone," and "Fentanyl Test Strips'' to identify studies published between January 1, 2013 and December 31, 2023. Endnote and Covidence software were used to catalog and manage citations for review of studies. Subsequently, studies that met inclusion criteria were then summarized using resulting themes. RESULTS: Twenty-seven articles met the inclusion criteria and were further abstracted for the scoping review. Of these articles, 77.7% (n = 21) included a naloxone intervention, while only 11.1% (n = 3) included a fentanyl test strip intervention. Furthermore, 30.1% (n = 8) of these studies were Latinx targeted, and 7.7% (n = 2) of the studies were adapted for Latinx populations. Four themes, including an overall lack of knowledge and awareness, a lack of access to harm reduction or opioid overdose prevention resources, an overall lack of culturally adapted and/or targeted interventions, and restrictive and punitive policies that limit the effectiveness of protective factors were highlighted in this scoping review. CONCLUSION: Limited published research exists on the use of emerging harm reduction behaviors, such as the use of naloxone and fentanyl test strips as community intervention strategies to prevent opioid overdose deaths. Even fewer publications exist on the targeting and cultural adaptation of harm reduction interventions responsive to Latinx communities, especially those using theoretical approaches or frameworks to support these interventions. Future research is needed to assess the unique needs of Latinx populations and to develop culturally responsive programs to prevent opioid-related overdose deaths among this population.

Overdose prevention centres as spaces of safety, trust and inclusion: A causal pathway based on a realist review.

ISSUES: Overdose prevention centres (OPC) are non-residential spaces where people can use illicit drugs (that they have obtained elsewhere) in the presence of staff who can intervene to prevent and manage any overdoses that occur. Many reviews of OPCs exist but they do not explain how OPCs work. APPROACH: We carried out a realist review, using the RAMESES reporting standards. We systematically searched for and then thematically analysed 391 documents that provide information on the contexts, mechanisms and outcomes of OPCs. KEY FINDINGS: Our retroductive analysis identified a causal pathway that highlights the feeling of safety - and the immediate outcome of not dying - as conditions of possibility for the people who use OPCs to build trust and experience social inclusion. The combination of safety, trust and social inclusion that is triggered by OPCs can - depending on the contexts in which they operate - generate other positive outcomes, which may include less risky drug use practices, reductions in blood borne viruses and injection-related infections and wounds, and access to housing. These outcomes are contingent on relevant contexts, including political and legal environments, which differ for women and people from racialised minorities. CONCLUSIONS: OPCs can enable people who live with structural violence and vulnerability to develop feelings of safety and trust that help them stay alive and to build longer term trajectories of social inclusion, with potential to improve other aspects of their health and living conditions.

Trends in toxicological findings in unintentional opioid or stimulant toxicity deaths in Québec, Canada, 2012-2021: Has Québec entered a new era of drug-related deaths?

INTRODUCTION: We aimed to describe rates and toxicological findings of unintentional opioid and stimulant toxicity deaths, 2012-2021. METHODS: The dataset included accidental deaths determined by the Coroner to be due to opioids or stimulants. We calculated annual crude mortality rates and described combinations of drugs identified in toxicological examinations of these deaths. We described temporal trends in the detection of specific opioids, stimulants, benzodiazepines (including novel benzodiazepines), gabapentinoids and z-drugs in deaths due to opioids and stimulants. RESULTS: Mortality rates increased over time, reaching their peak in 2020 and remaining high in 2021. In deaths due to opioids, there was a decline in the proportion of deaths involving pharmaceutical opioids after 2019, and a corresponding increase in the proportion of deaths with fentanyl detected. Benzodiazepines were often present in deaths due to opioids, with novel benzodiazepines increasing rapidly from 2019 onwards. Cocaine was the most frequently detected drug in deaths due to stimulants, but amphetamine/methamphetamine was detected in around half of all stimulant deaths from 2016 onwards. DISCUSSION AND CONCLUSIONS: Despite availability of a multitude of overdose prevention interventions, mortality rates due to drug toxicity have increased in Québec. Toxicological findings of these deaths suggest concerning shifts in the illicit drug market, with Québec potentially having entered a new era of elevated overdose mortality. Intervention scale-up is essential, but unlikely to be sufficient, to reduce drug-related mortality. Policy reform to address the root causes of drug toxicity deaths, including an unpredictable drug supply, strained health systems and socio-economic precarity, is essential.

Preventing overdoses involving stimulants: the POINTS study protocol.

BACKGROUND: In recent years, overdoses involving illicit cocaine, methamphetamine, and other stimulants have increased in the U.S. The unintentional consumption of stimulants containing illicit fentanyl is a major risk factor for overdoses, particularly in Massachusetts and Rhode Island. Understanding the drug use patterns and strategies used by people who use stimulants (PWUS) to prevent overdose is necessary to identify risk and protective factors for stimulant and opioid-involved overdoses. Mixed-methods research with people who distribute drugs (PWDD) can also provide critical information into the mechanisms through which fentanyl may enter the stimulant supply, and the testing of drug samples can further triangulate PWUS and PWDD perspectives regarding the potency and adulteration of the drug supply. These epidemiological methods can inform collaborative intervention development efforts with community leaders to identify feasible, acceptable, and scalable strategies to prevent fatal and non-fatal overdoses in high-risk communities. METHODS: Our overall objective is to reduce stimulant and opioid-involved overdoses in regions disproportionately affected by the overdose epidemic. To meet this long-term objective, we employ a multi-pronged approach to identify risk and protective factors for unintentional stimulant and opioid-involved overdoses among PWUS and use these findings to develop a package of locally tailored intervention strategies that can be swiftly implemented to prevent overdoses. Specifically, this study aims to [1] Carry out mixed-methods research with incarcerated and non-incarcerated people who use or distribute illicit stimulants to identify risk and protective factors for stimulant and opioid-involved overdoses; [2] Conduct drug checking to examine the presence and relative quantity of fentanyl and other adulterants in the stimulant supply; and [3] Convene a series of working groups with community stakeholders involved in primary and secondary overdose prevention in Massachusetts and Rhode Island to contextualize our mixed-methods findings and identify multilevel intervention strategies to prevent stimulant-involved overdoses. DISCUSSION: Completion of this study will yield a rich understanding of the social epidemiology of stimulant and opioid-involved overdoses in addition to community-derived intervention strategies that can be readily implemented and scaled to prevent such overdoses in two states disproportionately impacted by the opioid and overdose crises: Massachusetts and Rhode Island.

Atrial Fibrillation Secondary to Levothyroxine Overdose with Underlying Secondary Infection.

This case report presents the clinical course and management of a 62-year-old female patient with atrial fibrillation (AF) secondary to levothyroxine overdose along with an underlying secondary infection. The patient was admitted with sudden onset dyspnea, altered sensorium, and neurological deficits. Upon examination, she exhibited tachycardia, irregular heart sounds, and extensive crepitations in the respiratory system. Her electrocardiogram (ECG) showed an absent P wave with a varying RR interval. Laboratory investigations revealed abnormal thyroid function tests (TFTs) and raised polymorphonuclear cells, in addition to hyperglycemia. The patient was managed in the intensive care unit (ICU) with bilevel positive airway pressure (BiPAP) and supplemental oxygen, treated for AF with intravenous (IV) amiodarone, and her blood sugar was controlled with insulin infusion. Discontinuation of levothyroxine therapy was advised. Subsequently, her AF was terminated, and sinus rhythm was restored. Her neurological examination showed right-sided hemiplegia with aphasia. After 1 week of treatment, her TFTs normalized, and she was discharged on appropriate medication.

Rationalising the dose threshold for severe carbamazepine toxicity: a retrospective series.

INTRODUCTION: Carbamazepine causes dose-dependent toxicity in overdose. Resources commonly state that severe toxicity occurs with ingestions >50 mg/kg without supporting evidence. We aimed to compare ingested dose with clinical toxicity. METHODS: This was a retrospective series of patients reportedly ingesting carbamazepine >2,000 mg referred to a clinical toxicology unit and state poisons information centre. Medical records were reviewed to extract patient demographics, ingestion details, clinical effects and management. Severe toxicity was defined as the presence of coma (Glasgow Coma Scale <9), seizure, or hypotension (systolic blood pressure <90 mmHg). RESULTS: There were 69 presentations in 42 patients with a median ingested carbamazepine dose of 113 mg/kg (IQR: 71-151 mg/kg). Coma occurred in 10 cases, eight having ingested >200 mg/kg and the remaining two ingesting 113 mg/kg and 151 mg/kg, respectively. Seizures occurred in four cases (lowest ingested dose 143 mg/kg). Hypotension occurred in five cases (lowest ingested dose 113 mg/kg). DISCUSSION: Severe carbamazepine toxicity did not occur with reported ingestions <100 mg/kg and was uncommon in ingestions <200 mg/kg. CONCLUSION: Severe toxicity was common in ingestions >200 mg/kg. Using the suggested threshold of severe toxicity of >50 mg/kg appeared overly conservative in this series.