Valproate induced hyperammonemic encephalopathy: a rare adverse effect of a common drug

Abstract

Introduction. Sodium valproate or Valproic acid (VPA) is routinely used in management of epilepsy in neurology practice. It is a well-tolerated drug with mild side effects. Valproate induced encephalopathy (VPE) is a rare but serious adverse effect of this commonly used drug. Presentation of the case. We present a case of a 42-year-old female with valproate-induced encephalopathy. She had history of development of subacute onset of Parkinsonism followed by decreased sensorium after initiation of sodium valproate. On examination, she had tremor of both upper limbs and asterixis. Her serum ammonia was raised and valproate level was mildly raised. There was improvement in her symptoms after stoppage of valproate. Conclusion. We report a case of reversible Valproate induced encephalopathy (VPE) managed by stopping the offending drug. Clinical suspicion for VPE should be considered in any patients developing new neurological symptoms while on sodium valproate.