An apparent fatal valproic acid poisoning.

While extensive data on therapeutic concentrations of valproic acid in plasma exist, data on toxic or fatal levels are very limited and superficial, interpretation of isolated blood levels obtained post-mortem is therefore a difficult task. A case of sudden death is described here. The circumstances are known and strongly indicate a fatal, suicidal poisoning by valproic acid at a dose of 56.4 g. Valproic acid was quantified in tissues by gas chromatography, and its identity confirmed by gas chromatography/mass spectrometry. The tissue concentrations found post-mortem were as follows: blood 720 mg/L; liver 800 mg/kg; stomach contents 1700 mg. Phenobarbitone and propoxyphene were also present at therapeutic concentrations. This data should provide a useful reference for interpretive purposes.