Treatment of Valproate-Induced Hyperammonemia

The document discussed a case of valproate-induced hyperammonemia in a 79-year-old man with paranoid schizophrenia, who developed lethargy and confusion after his valproate dosage was increased. Despite normal liver enzymes and therapeutic valproate levels, his serum ammonia was elevated. Treatment involved discontinuing valproate, intravenous hydration, protein restriction, and lactulose, leading to rapid recovery. This was noted as the first report of using lactulose for this condition in an adult, with previous use in a child with Down's syndrome. The mechanism of valproate-induced hyperammonemia was linked to urea cycle inhibition, and the condition should be considered in patients on valproic acid presenting with lethargy or confusion.