Case: We report a case with concurrent ingestion of carbamazepine (CBZ) overdose and grapefruit juice. A 23-year-old man, with a history of epilepsy, was admitted to our emergency department 2 h after ingesting 10 g CBZ with 1 L grapefruit juice. On arrival, the patient's Glasgow Coma Scale score was 9 and he showed signs of restlessness. Grapefruit juice-like gastric fluid, with tablet residue, was observed in his stomach after we inserted a gastric tube. Our initial test detected a blood CBZ level of 41.5 mg/L.
Outcome: We treated the patient with gastric lavage, activated charcoal, and charcoal hemoperfusion. His blood CBZ level began to decrease after gastrointestinal decontamination, and he was discharged without any sequelae on day 9.
Conclusion: Gastric lavage or aspiration may be considered in cases where drug residue is found in the stomach, especially if materials are involved that might exacerbate the drug's toxicity.
Keywords: Blood concentration; carbamazepine; gastrointestinal decontamination; grapefruit juice; overdose.