Valproate induced hyperammonemic encephalopathy successfully treated with levocarnitine.

Valproate-induced hyperammonemic encephalopathy is an unusual but serious adverse effect that is usually characterized by the acute onset of impaired consciousness, focal neurological symptoms and increased seizure frequency. It has been reported to occur at therapeutic valproate levels. We report a patient who developed valproate-induced hyperammonemic encephalopathy after a short treatment with valproate and was successfully treated with levocarnitine. We discuss this patient and review the literature regarding the use of levocarnitine in similar patients.