Toxic dose
Toxicity from carbamazepine ingestion is mediated through both the drug and its active metabolite. Clinical features of carbamazepine poisoning are dose related. Sedation is likely with ingestions of more than 20 mg/kg; more significant central nervous system (CNS) depression, cardiovascular toxicity and gastrointestinal effects can occur after ingestions of more than 50 mg/kg.
Oxcarbazepine is a prodrug and its toxicity is less clearly dose related.
Drug-naive children who have ingested more than 20 mg/kg of carbamazepine, or more than 30 mg/kg of oxcarbazepine, require medical assessment and observation (see Potential toxic doses of some antiepileptic drugs in drug-naive children for potential toxic doses of some antiepileptic drugs in drug-naive children).