Rapid identification of potential nonsteroidal anti-inflammatory drug overdose-induced liver toxicity and prediction of follow-up exposure: Integrating bioanalytical and population pharmacokinetic assay.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most frequently used drugs that can cause liver toxicity. The aim of this study was to integrate bioanalytical and population pharmacokinetic (PopPK) assay to rapidly screen and quantify the concentrations of NSAIDs in plasma and monitor clinical safety. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous quantification of acetaminophen (APAP), flurbiprofen (FLB), aspirin (ASP), and ibuprofen (IBP), four commonly used NSAIDs. The PopPK model of the signature toxicant was analyzed based on the published literature. The LC-MS/MS method was successfully validated and applied to determine NSAID concentrations in patient plasma samples. APAP, ASP, and IBP data were best fitted using a one-compartment model, and FLB data were best fitted using a two-compartment model. Bootstrapping and visual predictive checks suggested that a robust and reliable pharmacokinetic model was developed. A fast, simple, and sensitive LC-MS/MS method was developed and validated for determining APAP, FLB, ASP, and IBP in human plasma. Combined with the PopPK model, this method was applied to rapidly analyze the concentrations of NSAIDs in clinical samples from patients presenting to the emergency department with acute liver dysfunction and monitored NSAIDs clinical safety.

Time-Dependent Changes in the Serum Levels of Neurobiochemical Factors After Acute Methadone Overdose in Adolescent Male Rat.

Acute methadone toxicity is a major public health concern which has adverse effects on brain tissue and results in recurrent or delayed respiratory arrest. Our study aimed to investigate the time-dependent changes in several serum biochemical markers of brain damage, spatial working memory, and the brain tissue following acute methadone overdose. Adolescent male rats underwent an intraperitoneal (i.p.) injection of 15 mg/kg methadone. In case of apnea occurrence, resuscitation was performed by a ventilatory pump and administrating naloxone (2 mg/kg; i.p.). The animals were classified into groups of treated rats; methadone and naloxone-Apnea (M/N-Apnea), M/N-Sedate, Methadone, Naloxone, and control (saline) groups. The serum levels of S100B, neuron-specific enolase (NSE), myelin basic protein factors, and (Lactate/Pyruvate) L/P ratio were evaluated at the time-points of 6, 24, and 48 h (h). We found that the alterations of S100B and L/P ratio were considerable in the M/N-Apnea and Methadone groups from the early hours post-methadone overdose, while NSE serum levels elevation was observed only in M/N-Apnea group with a delay at 48 h. Further, we assessed the spatial working memory (Y-maze test), morphological changes, and neuronal loss. The impaired spontaneous alternation behavior was detected in the M/N-Apnea groups on days 5 and 10 post-methadone overdose. The morphological changes of neurons and the neuronal loss were detectable in the CA1, striatum, and cerebellum regions, which were pronounced in both M/N-Apnea and Methadone groups. Together, our findings suggest that alterations in the serum levels of S100B and NSE factors as well as L/P ratio could be induced by methadone overdose with the presence or absence of apnea before the memory impairment and tissue injury in adolescent male rats.

Relatively mild symptoms after chronic overdose with a double-dose encorafenib: a case report.

Encorafenib (Braftovi) is indicated for the treatment of adult patients with unresectable or metastatic melanoma with a BRAF V600 mutation, in combination with binimetinib (Mektovi). According to the product label of encorafenib, there are no specific treatment recommendations in case of an overdose. We report on a 63-year-old man who ingested a double dose (900 mg) of encorafenib for 16 days. He developed overall minor chronic overdose symptoms such as nausea and vomiting grade 1 and muscle pain. Based on the most occurring adverse events of encorafenib, liver values, kidney function parameters and QTc interval were measured. Kidney function parameters were normal, whereas liver values were slightly increased (grade 1) and QTc slightly prolonged. The plasma concentration 3 h after the last dose was 2110 ng/mL. We describe the course of a case with a chronic overdose during 16 days of the double dose of encorafenib as well as the followed approach, which could be taken into account when observing an encorafenib overdose. Providing information in times of Covid-19 is challenging, but remains necessary for good clinical care.

Time to Peak International Normalized Ratio Rise in Acute and Acute-on-Chronic Warfarin Overdoses.

ABSTRACT: Guidelines exist on the management of supratherapeutic/subtherapeutic international normalized ratio (INR) values for patients on warfarin. However, there is a paucity of the literature relating to an acute overdose of warfarin. This is a retrospective cohort study for all acute and acute-on-chronic (AOC) warfarin overdoses reported to the Maryland Poison Center in patients ≥12 years between January 1st, 2000, until October 31st, 2019, managed in a health care facility. The primary outcome was to determine the time after presentation to peak INR. Secondary outcomes included risk factors associated with INR >10 and describing patient characteristics. A total of 163 overdoses were included, 68 acute and 95 AOC. In patients who did not receive reversal therapies, INR peaked at a median value of 3.8 (interquartile range 2.6-5.5) between 24 and 36 hours. The median time to phytonadione was 22.0 hours. Most patients received phytonadione (62.0%), with fewer receiving blood products (16.6%). The median warfarin dose ingested was 75 mg. The AOC group had a greater mean age (56 vs. 43 years), median INR value (2.4 vs. 1.4), and men (62.1% vs. 41.2%). Factors associated with an INR > 10 included initial INR and reported quantity ingested. Peak INR was greater in the AOC than the acute overdose group (6.1 vs. 3.4), although the bleeding rate was similar. Peak INR values after warfarin overdose occur between 24 and 36 hours after presentation. Initial INRs and reported quantity ingested may be useful to predict those needing treatment.

Biomarkers of endothelial dysfunction in cocaine overdose and overdose-related cardiovascular events.

Overdose of stimulant drugs has been associated with increased risk of adverse cardiovascular events (ACVE), some of which may be ascribed to endothelial dysfunction. The aims of this study were to evaluate biomarkers of endothelial dysfunction in emergency department (ED) patients with acute cocaine overdose and to assess the association between in-hospital ACVE in ED patients with any acute drug overdose. This was a prospective consecutive cohort study over 9 months (2015-2016) at two urban, tertiary-care hospital EDs. Consecutive adults (≥18 years) presenting with suspected acute drug overdose were eligible and separated into three groups: cocaine (n = 47), other drugs (n = 128), and controls (n = 11). Data were obtained from medical records and linked to waste serum specimens, sent as part of routine clinical care, for biomarker analysis. Serum specimens were collected and analyzed using enzyme-linked immunosorbent assay kit for three biomarkers of endothelial dysfunction: (a) endothelin-1 (ET-1), (b) regulated upon activation normal T cell expressed and secreted (RANTES), and (c) soluble intercellular adhesion molecule-1 (siCAM-1). Mean siCAM was elevated for cocaine compared with controls and other drugs (p < .01); however, mean RANTES and ET-1 levels were not significantly different for any drug exposure groups. Receiver operating characteristics curve analysis for prediction of in-hospital ACVE revealed excellent performance of siCAM-1 (area under curve, 0.86; p < .001) but lack of predictive utility for either RANTES or ET-1. These results suggest that serum siCAM-1 is a viable biomarker for acute cocaine overdose and that endothelial dysfunction may be an important surrogate for adverse cardiovascular events following any drug overdose.

Prognostic utility of lactate concentrations and kinetics to predict adverse events associated with acute drug overdose.

OBJECTIVE: Clinical research on drug intoxication is necessary for appropriate action in emergency departments (EDs). However, currently, there are no evident biomarkers for predicting adverse events (AEs) in patients with drug intoxication. We aimed to evaluate the prognostic value of serum lactate concentrations and lactate kinetics for AEs such as cardiogenic or respiratory failure in patients admitted to the ED with acute drug overdose. METHODS: We conducted a single-center retrospective study by reviewing the prospective suicide registry of patients visiting the ED. The primary outcome was composite AEs at any point during the ED visit or hospital stay. RESULTS: A total of 566 patients with acute drug overdose were enrolled in this study. Of these, 62 patients had AEs, whereas 363 patients did not, yielding an AE rate of 14.6%. The median 0 h lactate concentrations in the AE and non-AE groups were 2.7 [2.1-5.1] mmol/L and 2.1 [1.4-2.9] mmol/L, respectively (p < 0.001). The median 6 h lactate concentrations in the AE and non-AE groups were 2.0 [1.5-3.9] mmol/L and 1.3 [0.9-2.2] mmol/L, respectively (p < 0.001). The area under the curve of lactate at 0 h for predicting AEs was 0.705 (95% CI: 0.659-0.748). The optimal lactate cutoff point was 4.2 mmol/L (37.1% sensitivity, 92.8% specificity). Multivariable analysis using a stepwise backward method showed that the 0 h lactate concentration was associated with AEs in acute drug intoxication after adjusting for confounders (adjusted OR of 0 h lactate, 1.47; 95% CI, 1.23-1.77). However, the 6 h lactate concentrations, lactate clearance, and delta lactate levels did not predict the outcomes. CONCLUSION: Lactate concentrations and kinetics in patients admitted to the ED with an acute drug overdose exhibited limited prognostic utility in predicting AEs and should be interpreted with caution when considered for clinical decision-making.

Early acetaminophen-protein adducts predict hepatotoxicity following overdose (ATOM-5).

BACKGROUND & AIMS: Acetaminophen-protein adducts are specific biomarkers of toxic acetaminophen (paracetamol) metabolite exposure. In patients with hepatotoxicity (alanine aminotransferase [ALT] >1,000 U/L), an adduct concentration ≥1.0 nmol/ml is sensitive and specific for identifying cases secondary to acetaminophen. Our aim was to characterise acetaminophen-protein adduct concentrations in patients following acetaminophen overdose and determine if they predict toxicity. METHODS: We performed a multicentre prospective observational study, recruiting patients 14 years of age or older with acetaminophen overdose regardless of intent or formulation. Three serum samples were obtained within the first 24 h of presentation and analysed for acetaminophen-protein adducts. Acetaminophen-protein adduct concentrations were compared to ALT and other indicators of toxicity. RESULTS: Of the 240 patients who participated, 204 (85%) presented following acute ingestions, with a median ingested dose of 20 g (IQR 10-40), and 228 (95%) were treated with intravenous acetylcysteine at a median time of 6 h (IQR 3.5-10.5) post-ingestion. Thirty-six (15%) patients developed hepatotoxicity, of whom 22 had an ALT ≤1,000 U/L at the time of initial acetaminophen-protein adduct measurement. Those who developed hepatotoxicity had a higher initial acetaminophen-protein adduct concentration compared to those who did not, 1.63 nmol/ml (IQR 0.76-2.02, n = 22) vs. 0.26 nmol/ml (IQR 0.15-0.41; n = 204; p <0.0001), respectively. The AUROC for hepatotoxicity was 0.98 (95% CI 0.96-1.00; n = 226; p <0.0001) with acetaminophen-protein adduct concentration and 0.89 (95% CI 0.82-0.96; n = 219; p <0.0001) with ALT. An acetaminophen-protein adduct concentration of 0.58 nmol/ml was 100% sensitive and 91% specific for identifying patients with an initial ALT ≤1,000 U/L who would develop hepatotoxicity. Adding acetaminophen-protein adduct concentrations to risk prediction models improved prediction of hepatotoxicity to a level similar to that obtained by more complex models. CONCLUSION: Acetaminophen-protein adduct concentration on presentation predicted which patients with acetaminophen overdose subsequently developed hepatotoxicity, regardless of time of ingestion. An adduct threshold of 0.58 nmol/L was required for optimal prediction. LAY SUMMARY: Acetaminophen poisoning is one of the most common causes of liver injury. This study examined a new biomarker of acetaminophen toxicity, which measures the amount of toxic metabolite exposure called acetaminophen-protein adduct. We found that those who developed liver injury had a higher initial level of acetaminophen-protein adducts than those who did not. CLINICAL TRIAL REGISTRATION: Australian Toxicology Monitoring (ATOM) Study-Australian Paracetamol Project: ACTRN12612001240831 (ANZCTR) Date of registration: 23/11/2012.

Determination of the cut-off prothrombin time to estimate plasma rivaroxaban overdose status.

Laboratory monitoring of rivaroxaban (RIV) is required under certain conditions. Mass spectrometry and anti-factor Xa assays are the recommended methods, which may not be readily available. Prothrombin time (PT) is the most widely used and simple coagulation assay. To set the cutoff PT and international normalized ratio (INR) to estimate RIV overdose status. RIV-spiked pooled normal plasma was used. PT test was performed using a CA-7000 coagulometer and Thromborel S reagent. The precise measurement of RIV concentration at the cut-off PT was evaluated according to the Clinical and Laboratory Standard Institute (CLSI) EP12-A2 guideline. The RIV concentration at 275 ng/mL was analyzed using 40 replicates. Receiver operating characteristic (ROC) analysis was performed to determine the cutoff value for the determination of RIV potential overdose status. An imprecision estimation of PT was conducted with 220.00 ng/mL, 247.50 ng/mL, 261.25 ng/mL, 288.75 ng/mL, 302.50 ng/mL and 330.00 ng/mL concentrations of RIV in 60 replicates. According to the ROC analysis, the cutoff clotting times and INR values to determine the overdose status of RIV were 13.45 s and 1.39. With these values, there was a 92.6% probability that plasma samples with RIV concentration ≤ 247.50 ng/mL yielded consistently negative (on-therapy dose) results, and those with ≥ 302.50 ng/mL yield consistent positive (potential overdose) results using our PT assay. PT with a reliable cutoff clotting time and INR can be used to determine the potential overdose status of RIV to facilitate the diagnosis and treatment by controlling the dose.

A comparison of blood toxicology in fatalities involving alcohol and other drugs in patients with an opioid use disorder treated with methadone, buprenorphine, and implant naltrexone.

Background: Methadone, buprenorphine, and implant naltrexone have comparable efficacy in preventing death from drug intoxication during treatment, but there may be differences between treatments in the specific drugs contributing to death and in the risk of death during different phases of treatment.Objective: The objective of this study was to compare concentrations of individual drugs in decedents for evidence that the three medications use to treat opioid use disorders differed in the protection they offered against fatal overdose.Methods: Fatalities with a primary or co-diagnosis of alcohol or other drug poisoning in patients treated with methadone (n = 66, 74.2% male), buprenorphine (n = 54, 74.1% male), or naltrexone (n = 28, 85.7% male) were identified by combining treatment (Monitoring of Drugs of Dependence System and clinical records) and mortality records (Western Australian Death Registry). Quantitative postmortem blood drug analysis data were obtained for drug-related deaths. The presence/absence of drugs were compared between the three medication groups and between phases of treatment (on-treatment/off-treatment).Results: Opioids (89.8%) and benzodiazepines (76.2%) were most commonly identified in postmortem blood. The three medication groups did not differ materially in the drugs present postmortem, except that alcohol was less prevalent in naltrexone-treated cases. Morphine or heroin intoxication was implicated in more patients dying off-treatment than on-treatment but levels of morphine and other drugs were comparable across the two phases.Conclusion: Comparisons of postmortem concentrations of specific drugs indicated that patients treated with methadone, buprenorphine, and implant naltrexone had comparable susceptibilities to lethal co-intoxication and that similar drug mixtures contributed to death.

The Clinical Value of Routine Acetaminophen Level Screening in Pediatric Patients Presenting to the Emergency Department.

BACKGROUND: Acetaminophen is the most common drug involved in pediatric poisonings, both intentionally and accidentally, and is the leading cause of acute liver failure among all age groups. OBJECTIVES: To define the characteristics of patients admitted to a pediatric emergency department (ED) where serum acetaminophen concentrations were measured, and to determine which variables are associated with significant risk of acetaminophen toxicity. METHODS: Acetaminophen serum concentrations were measured, in a retrospective case series, of patients younger than 18 years who had been admitted to the ED at Shamir Medical Center between 1 January 2008 and 31 December 2015. RESULTS: During the study period 180,174 children were admitted to the ED. Acetaminophen serum concentrations were measured in 209 (0.12%) patients. Mean age was 12.4 ± 5.9 years. Elevated liver enzymes were found in 12 patients, 5 of whom had documented acute liver injury. All five were older than 11years.Two cases of acute liver injury were attributable to acetaminophen ingestion. In both cases the cause was intentional overdose. Univariate analysis showed a significant (P < 0.05) correlation between detectable acetaminophen blood level and a positive history of drug or acetaminophen ingestion, and suicide attempt. Not all children with non-severe acetaminophen poisoning had been diagnosed during the study period. A positive history of acetaminophen ingestion was associated with a 28-fold higher risk for detectable acetaminophen blood level. CONCLUSIONS: In the absence of a positive history of acetaminophen ingestion and in young children with accidental intoxication, the risk of hepatotoxicity is relatively low.

Acetaminophen is Undetectable in Plasma From More Than Half of Patients Believed to Have Acute Liver Failure Due to Overdose.

BACKGROUND & AIMS: Evaluation of patients with acute liver injury (ALI) or acute liver failure (ALF) often includes measurement of plasma levels of acetaminophen, to determine exposure and/or toxicity. However, once liver injury has developed, acetaminophen might be undetectable in plasma. We investigated the association between level of acetaminophen measured and outcomes of patients designated as having ALF or ALI due to acetaminophen toxicity. METHODS: We performed a retrospective analysis of data from 434 subjects in the Acute Liver Failure Study Group who met criteria for ALF (coagulopathy and hepatic encephalopathy within 26 weeks of the first symptoms, without pre-existing liver disease) or ALI (severe liver injury with coagulopathy but no encephalopathy) due to acetaminophen toxicity from January 1, 2010 through December 31, 2014. We collected data on patient demographics, biochemical features, reported acetaminophen use, N-acetylcysteine therapy, liver transplant, and outcomes. Descriptive statistics were used to assess patient demographics, clinical characteristics, and outcomes whereas differences in continuous variables between patients with vs without acetaminophen detection on admission were analyzed using the Wilcoxon rank-sum test. The primary aim was to determine the proportion of patients with detectable plasma levels of acetaminophen. RESULTS: Acetaminophen was undetectable in serum samples from 227 patients (52%). There were no significant differences between groups of patients with detectable vs undetectable levels in demographic features, alcohol use, median levels of alanine aspartate, or use of N-acetylcysteine (given to 94.7% of patients with detectable acetaminophen vs 95.9% of those with undetectable acetaminophen; P=.63). We observed a significant difference in median dose taken between patients with detectable (29,500 mg; interquartile range, 15,000 mg-50,007 mg) vs no detectable parent compound (14,950 mg; interquartile range, 3960 mg-25,000) (P=.003). A lower proportion of patients with detectable plasma levels of acetaminophen (72.3%) survived without a liver transplant than of patients with undetectable levels (86.3%) in univariate analysis (P=.0006), although this was not significant in multivariable analysis (P=.12). Although most patients had unintentional overdoses, a higher proportion of patients with suicidal overdoses (43%) had detectable levels of acetaminophen than patients with accidental overdoses (29.3%; P=.01). CONCLUSION: More than half of patients who present at the hospital with acetaminophen-induced ALI or ALF have undetectable levels of acetaminophen. Clinicians should not exclude acetaminophen toxicity because of undetectable levels or withhold N-acetylcysteine for patients with ALI or ALF when acetaminophen toxicity is suspected.

Fighting Fire with Fire: Development of Intranasal Nalmefene to Treat Synthetic Opioid Overdose.

The dramatic rise in overdose deaths linked to synthetic opioids (e.g., fentanyl, carfentanil) may require more potent, longer-duration opiate antagonists than naloxone. Both the high affinity of nalmefene at µ opiate receptors and its long half-life led us to examine the feasibility of developing an intranasal (IN) formulation as a rescue medication that could be especially useful in treating synthetic opioid overdose. In this study, the pharmacokinetic properties of IN nalmefene were compared with an intramuscular (i.m.) injection in a cohort of healthy volunteers. Nalmefene was absorbed slowly following IN administration, with a median time to reach Cmax (Tmax) of 2 hours. Addition of the absorption enhancer dodecyl maltoside (Intravail, Neurelis, Inc., Encinitas, CA) reduced Tmax to 0.25 hour and increased Cmax by ∼2.2-fold. The pharmacokinetic properties of IN nalmefene (3 mg) formulated with dodecyl maltoside has characteristics consistent with an effective rescue medication: its onset of action is comparable to an i.m. injection of nalmefene (1.5 mg) previously approved to treat opioid overdose. Furthermore, the Cmax following IN administration was ∼3-fold higher than following i.m. dosing, comparable to previously reported plasma concentrations of nalmefene observed 5 minutes following a 1-mg i.v. dose. The high affinity, very rapid onset, and long half-life (>7 hours) of IN nalmefene present distinct advantages as a rescue medication, particularly against longer-lived synthetic opioids.

Treatment of γ-Hydroxybutyric Acid and γ-Butyrolactone Overdose with Two Potent Monocarboxylate Transporter 1 Inhibitors, AZD3965 and AR-C155858.

The illicit use of γ-hydroxybutyric acid (GHB), and its prodrug, γ-butyrolactone (GBL), results in severe adverse effects including sedation, coma, respiratory depression, and death. Current treatment of GHB/GBL overdose is limited to supportive care. Recent reports indicate that GHB-related deaths are on the rise; a specific treatment may reduce lethality associated with GHB/GBL. Pretreatment with inhibitors of monocarboxylate transporter 1 (MCT1), a transporter that mediates many of the processes involved in the absorption, distribution (including brain uptake), and elimination of GHB/GBL, has been shown to prevent GHB-induced respiratory depression by increasing the renal clearance of GHB. To identify whether MCT1 inhibition is an effective treatment of GHB overdose, the impact of two MCT1 inhibitors, (S)-5-(4-hydroxy-4-methylisoxazolidine-2-carbonyl)-1-isopropyl-3-methyl-6-((3-methyl-5-(trifluoromethyl)-1H-pyrazol-4-yl)methyl)thieno[2,3-day]pyrimidine-2,4(1H,3H)-dione (AZD3965) and 6-[(3,5-dimethyl-1H-pyrazol-4-yl)methyl]-5-[[(4S)-4-hydroxy-2-isoxazolidinyl]carbonyl]-3-methyl-1-(2-methylpropyl)thieno[2,3-day]pyrimidine2,4(1H,3H)-dione (AR-C155858), on the toxicokinetics and toxicodynamics of GHB/GBL was assessed when the administration of the inhibitor was delayed 60 and 120 minutes (post-treatment) after administration of GHB/GBL. AR-C155858 and AZD3965 reduced the toxicodynamic effects of GHB when GHB was administered intravenously, orally, or orally as the prodrug GBL. The impact of these inhibitors on GHB toxicokinetics was dependent on the route of GHB administration and the delay between GHB/GBL administration and administration of the MCT1 inhibitor. The reduction in GHB plasma exposure did not explain the observed effect of MCT1 inhibition on GHB-induced respiratory depression. The efficacy of MCT1 inhibition on GHB toxicodynamics is likely driven by the pronounced reduction in GHB brain concentrations. Overall, this study indicates that inhibition of MCT1 is an effective treatment of GHB/GBL overdose.

Self-poisoning with 60 tablets of Apixaban, a pharmacokinetics case report.

A 67-year-old man was admitted to the emergency department about 5 h after deliberate self-poisoning with 300 mg of Apixaban. The clinical examination did not show any organ dysfunctions or haemorrhagic signs, and the patient's life was not in danger. The first analysis, upon admission, showed a concentration of 2655 µg l-1 of Apixaban. The Cmax was observed 17 h after the intake (3654 µg l-1 ), about four times the classical Tmax value (median [range]: 4 h [2-4]). The Apixaban was then eliminated following a first order elimination with a calculated half-life of 10.8 h. The anti-Xa activity seems to be linearly related to concentration up to 4000 µg l-1 . This report suggests that the use of activated charcoal should be effective up to 17 h after a massive intake.

Levocarnitine for the Treatment of Valproic Acid-Induced Hyperammonemic Encephalopathy in Children: The Experience of a Large, Tertiary Care Pediatric Hospital and a Poison Center.

BACKGROUND: Although rare, symptomatic hyperammonemia is sometimes associated with valproic acid (VPA), especially in children. L-carnitine (levocarnitine), sometimes classified as an essential amino acid, is vital to mitochondrial utilization of fatty acids and can be helpful in treating this condition. The data supporting this, however, are limited. STUDY QUESTION: The aim of the study was to illustrate the role of L-carnitine in the treatment of patients with VPA-induced hyperammonemic encephalopathy (VPE) at 2 different institutions. METHODS: Medical records of affected patients were reviewed; data collected included exposure history, clinical manifestations, physical examination, and laboratory values. RESULTS: There were 13 cases of VPE; 12 were associated with therapeutic dosing and 1 with an overdose. The maximum ammonia concentration was 557 µmol/L, and blood concentrations of VPA ranged from 68 to 600 µg/mL (therapeutic range 50-100 µg/mL). In all cases, liver function tests were normal or only mildly increased. In this study, 12 patients received a daily dose of L-carnitine 100 mg/kg, and 1 received 200 mg/kg (intravenous infusion over 30 minutes) divided every 8 hours until clinical improvement. All patients made a full recovery. None developed adverse effects or reactions, and no cases of toxicity were reported. CONCLUSION: Our series suggests that intravenous L-carnitine, at a dose of 100 mg·kg·d in 3 divided doses each over 30 minutes until clinical improvement occurs, is a safe and effective treatment in the management of VPE in children.

Management of lamotrigine overdose using hemodialysis.

Lamotrigine [LTG] is primarily an anti-epileptic drug used to treat seizure disorders, depression, and bipolar disease. It is generally well tolerated with limited side effects reported during routine use. Adverse events after overdose include neurotoxicity in the form of sedation and seizure activity, as well as cardiopulmonary toxicity in the form of sodium-channel blockade and cardiovascular collapse. There is no consensus regarding the role of hemodialysis (HD) in management of lamotrigine toxicity. Based on pharmacological properties, LTG is a candidate for extracorporeal removal, however, the successful use of HD for the treatment of this poisoning is not well described. We report the case of a 44 year-old female after a LTG overdose that experienced prolonged sedation that was ultimately treated with HD with an excellent response.

Re-elevation of serum amlodipine level after lipid emulsion therapy in an overdose case.

WHAT IS KNOWN AND OBJECTIVE: Amlodipine overdose is common; however, the dose and timing of intravenous lipid emulsion (ILE) therapy as a management strategy remain debatable. CASE DESCRIPTION: A 73-year-old man received a single bolus (1.5 mL/kg) of ILE therapy following massive ingestion of multiple drugs, including amlodipine. After approximately 20 hours of ILE therapy, the serum amlodipine level that had decreased from 90.2 to 49.9 ng/mL increased to 70.8 ng/mL. WHAT IS NEW AND CONCLUSION: A single bolus (1.5 mL/kg) of ILE therapy is probably insufficient to completely capture and partition serum amlodipine following amlodipine overdose.

Detection of synthetic cannabinoid intoxication in the Emergency Department: when routine toxicological tests are not enough. / Detección de la intoxicación por cannabinoides sintéticos en Urgencias: cuando las pruebas toxicológicas rutinarias no bastan.

Letter to the editor.

Carta al Editor.

Prognostic Utility of Initial Lactate in Patients With Acute Drug Overdose: A Validation Cohort.

STUDY OBJECTIVE: Previous studies have suggested that the initial emergency department (ED) lactate concentration may be an important prognostic indicator for inhospital mortality from acute drug poisoning. We conduct this cohort study to formally validate the prognostic utility of the initial lactate concentration in a larger, distinct patient population with acute drug overdose. METHODS: This observational, prospective, cohort study was conducted during 5 years at 2 urban teaching hospitals. Consecutive adult ED patients with acute drug overdose had serum lactate levels tested as part of clinical care. The primary outcome was inpatient fatality. Receiver operating characteristics were plotted to determine optimal cut points, test characteristics, area under the curve, odds ratios, and 95% confidence intervals (CIs). RESULTS: Of 3,739 patients screened, 1,406 were analyzed (56% women; mean age 43.1 years) and 24 died (1.7%). The difference in mean initial lactate concentration was 5.9 mmol/L (95% CI 3.4 to 8.1 mmol/L) higher in patients who died compared with survivors. The area under the curve for prediction of fatality was 0.85 (95% CI 0.73 to 0.95). The optimal lactate cut point for fatality was greater than or equal to 5.0 (odds ratio 34.2; 95% CI 13.7 to 84.2; 94.7% specificity). Drug classes for which lactate had the highest utility were salicylates, sympathomimetics, acetaminophen, and opioids (all area under the curve ≥0.97); lowest utility was for diuretics and angiotensin-converting enzyme inhibitors. CONCLUSION: Initial lactate concentration is a useful biomarker for early clinical decisionmaking in ED patients with acute drug overdose. Studies of lactate-tailored management for these patient populations are warranted.

Hypoglycemia and Sudden Death During Treatment With Methadone for Opiate Detoxification.

CLINICAL FEATURES: We present a case of a middle-aged man admitted to an inpatient detoxification facility for withdrawal of intranasal heroin, alprazolam, and ethanol. The patient was placed on methadone and chlordiazepoxide tapers. Ondansetron and trazodone were prescribed as needed for symptom control. On the third hospital day, the patient was found unresponsive with blood glucose of 40 mg/dL. He had no history of glucose dysregulation. The patient was pronounced dead shortly thereafter. Methadone overdose was ruled the cause of death. THERAPEUTIC CHALLENGES: There have been studies linking methadone with glucose dysregulation. Hypoglycemia can induce changes in the electrical system in the heart, including lengthening QT interval, lengthening repolarization, and causing ST wave changes. In addition, there have been studies linking methadone treatment to QT interval prolongation and torsade de pointes. Ondansetron and trazodone have both been associated with cardiac conduction abnormalities. SOLUTION: We recommend initial blood glucose and cardiac monitoring in patients taking methadone 40 mg daily or higher.