Reversible dementia and gait disturbance after prolonged use of valproic acid.

Valproic acid (VPA) has been reported to cause cognitive decline and parkinsonism that are reversed with cessation of medication. Common imaging findings among these reports demonstrate reversible cortical pseudoatrophy and enlargement of the lateral ventricles. This case exemplifies these adverse effects of VPA which can cause reversible neurological symptoms even in long-term treated patients and can present as dementia syndromes such as normal pressure hydrocephalus.