[Valproic acid in prophylaxis of bipolar disorder. A case of valproate-induced encephalopathy].

A 28-year-old patient with a 5-year history of bipolar disorder developed signs of encephalopathy 2 weeks after the addition of valproic acid to his treatment regimen of doxepine, risperidone, and biperidene. The clinical signs were drowsiness, ataxic gait, asterixis, and a generalized epileptic seizure. Discontinuation of valproic acid gradually resulted in complete remission of these symptoms. Valproate encephalopathy has been described mainly in patients receiving anticonvulsant polytherapy. This complication might become more prevalent in psychiatric pharmacotherapy due to the increasing use of valproic acid.