We present a case of acute oxcarbazepine and atomoxetine overdose combined with excess quetiapine in a 19-y-old male. The patient ingested approximately 36 g oxcarbazepine (514 mg/kg), 1.2 g atomoxetine (17 mg/kg), and 9 mg Quetiapine (128 mg/kg). Central nervous system (CNS) depression with initial unresponsiveness developed within 1 h of ingestion, necessitating intubation for airway protection. Despite aggressive therapy with whole bowel irrigation and charcoal administration, the patient's somnolence persisted for 4 d, punctuated by occasional violent outbursts. Prolonged QTc was noted initially, but normalized within 4 d. This case suggests that acute overdose of oxcarbazepine and atomoxetine combined with quetiapine is associated with rapid and prolonged CNS depression.