Prevalence and Outcomes of Carbamazepine Toxicity in the Emergency Department: A Single-center Retrospective Study

Background: Carbamazepine (CBX) is widely used for various medical conditions, but its associated toxicity poses significant clinical concerns. This study aims to provide insights into the clinical presentations, management strategies, and outcomes of CBX toxicity cases in an emergency department (ED) setting. Methodology: This was a 10-year retrospective cohort chart review study, including all patients with elevated CBX levels. Data on clinical features, CBX levels, laboratory findings, electrocardiograms (ECGs), patient management, and outcomes were analyzed. Cases were categorized as acute or chronic toxicity. Results: Out of the 1,965 medical charts reviewed, we included 70 patients with CBX levels above the therapeutic range (prevalence: 3.6%). Chronic CBX toxicity cases (55.7%) were predominant, with gastrointestinal (GI) symptoms being the most common. Most patients presented with isolated CBX overdoses (88.6%), while mixed overdoses (11.4%) were less frequent. Patients were categorized based on CBX levels: 44 had mild toxicity (>51 mu mol/L), and 26 had moderate toxicity (>85 mu mol/L). Within the mild group, 15 patients experienced acute toxicity, compared to 16 patients in the moderate group. Four patients who had mixed overdoses and low sensorium required intubation and mechanical ventilation. Three patients received activated charcoal (AC), and another 3 patients received multiple doses of AC to reduce drug absorption. The majority of patients (65.7%) required hospital admission, underscoring the seriousness of CBX toxicity. There were no fatalities among these 70 patients. Conclusion: This study emphasizes the importance of a systematic approach to assessing and managing CBX toxicity, considering its diverse clinical presentations and variations in serum CBX levels.