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Context:Lamotrigine is a broad-spectrum anticonvulsant commonly used to treat seizure and bipolar mood disorders. Evidence from case series and retrospective studies indicate that lamotrigine overdose is usually benign. However, there are reported cases of cardiac arrest and mortality following lamotrigine overdose. We undertook a systematic review of the literature on lamotrigine overdoses to better understand the clinical severity, the relevance of serum concentrations, and therapeutic interventions for overdose. Objectives:To characterize manifestations of acute lamotrigine overdose, determine if serum concentrations predict poisoning severity, and evaluate the effectiveness of overdose management interventions. Methods:We performed a literature search across eight databases, including Medline, EMBASE, and the Cochrane Library, from database inception to April 2014. Major bibliographic databases were updated on 31 May 2017. Articles were eligible if they described acute or acute on chronic lamotrigine overdose. At least one serum lamotrigine concentration had to be reported for inclusion. Reports on chronic poisoning, studies describing adverse effects of therapeutic use, and animal studies were excluded. Results:We retrieved 6238 records; 48 (51 cases) met the inclusion criteria. Cases primarily involved adults (70.6%). Potentially life-threatening symptoms of overdose included seizures (55%), Glasgow Coma Scale ≤8 (20%), hypotension (12%), and wide complex tachycardia (WCT) and cardiac arrest (6%). Among the 25 cases exposed to lamotrigine alone (13 adult; 12 pediatric), 2 adult fatalities occurred (4 g and 7.5 g ingested) and 8 pediatric cases experienced seizures (all children ≤3.5-years-old, 75% without an underlying seizure disorder, ≥ 525 mg ingested). The lowest seizure-associated serum concentration was 3.8 mg/L and 25.6 mg/L for pediatric and adult patients, respectively, suggesting children may be more susceptible to CNS toxicity. Cardiovascular toxicities occurred primarily in adult patients (threshold >25 mg/L). Overdose interventions included benzodiazepines (53%), propofol or barbiturates (14%), NaHCO3(20%), lipid therapy (12%), and extracorporeal elimination (10%). NaHCO3yielded no response in four of nine cases with conduction delays; however, two of the four cases subsequently responded with lipid therapy. Conclusions:Most cases reporting lamotrigine exposures observed mild or no toxicity; however, large exposures were associated with severe CNS depression, seizures, cardiac conduction delays, wide complex tachycardia, and death. In adults with a serum concentration >25 mg/L, severe toxicity may occur. In patients ≤3.5 years of age, ingestions of ≥525 mg may produce severe CNS depression and seizures. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]