Study objective: To describe the clinical effects of carbamazepine ingestion in a pediatric population.
Design: Case series of prospectively evaluated patients and a historical retrospective group.
Participants: All patients younger than 18 years who presented to an urban emergency department with history of carbamazepine ingestion and positive laboratory confirmation.
Interventions: Patient demographics, findings on physical examination, serum carbamazepine levels, analysis of 12-lead ECGs, and time and doses of activated charcoal were recorded.
Results: Seventy-seven patients were enrolled, of whom 17 were evaluated prospectively. Serum carbamazepine levels were greater than 12 micrograms/mL (50 mumol/L) in 61 patients. In those 61 patients, mean peak serum level was significantly higher in patients with dystonic reactions (P = .009), coma (P = .002), and apnea (P = .008) than in patients without these symptoms. There was no significant difference in mean peak serum levels between patients with and without seizures. Serum carbamazepine half-life was significantly shorter (P = .022) in patients who received multiple doses of activated charcoal (8.2 +/- 1.6 hours) than in those who received a single dose (12.1 +/- hours).
Conclusion: Pediatric patients with suspected carbamazepine ingestion are at higher risk for dystonic reactions, coma, and apnea if the peak serum carbamazepine level exceeds 28 micrograms/mL (117 mumol/L). The development of seizures is not related to peak serum level. Multiple doses of activated charcoal can significantly shorten serum carbamazepine half-life.