CDHB
Valproic acid is an anticonvulsant that is commonly used as a mood stabilizer. In overdose, response may be variable and development of toxicity may be delayed up to 12 hours.
Elimination by haemodialysis may be considered in cases where severe toxicity is anticipated (dose >1000 mg/kg) and ideally before multiorgan dysfunction has occurred (consult ICU).
Effects of sodium valproate overdosage |
|
Dose |
Effect |
<200 mg/kg |
Asymptomatic or mild drowsiness and/or ataxia |
200-400 mg/kg |
Variable CNS depression |
400-1000 mg/kg |
Significant CNS depression. Coma requiring intubation may occur up to 12 hours post ingestion. Multiorgan toxicity more likely in higher dose range. |
>1000 mg/kg |
Potentially lethal with profound coma and multi-organ failure (cerebral oedema, hypotension, lactic acidosis, hypoglycaemia, hyponatraemia, rarely hypernatraemia, etc) |
Topic Code: 35089