Case: Valproat-Induced Hyperammonemic Encephalopathy


  • Aysel Ünlüsoy Aksu Gazi University
  • Ebru Petek Arhan Gazi University
  • Ercan Demir Gazi University
  • Ayşe Aysima Özçelik Gaziantep University
  • Ayşe Serdaroğlu Gazi University
  • Kıvılcım Gücüyener Gazi University


Valproate induced hyperammonemic encephalopathy (VHE) is a severe adverse effect of medicine. An epileptic patient with an acute hyperammonemia after the addition of valproic acid to his treatment  presented with acute mental status changes consistent with encephalopathy. Notably, plasma ammonia level was 2 times of the upper limit, despite normal liver function tests. Plasma valproic acid level was in the therapeutic range. His symptoms resolved with the discontinuation of valproic acid and L-carnitine administration. We discuss this case and review the possible mechanisms of valproic acid–associated encephalopathy and the efficacy of L-carnitine. 

Author Biographies

Aysel Ünlüsoy Aksu, Gazi University


Ebru Petek Arhan, Gazi University

Pediatric Neurology

Ercan Demir, Gazi University

Pediatric Neurology

Ayşe Aysima Özçelik, Gaziantep University

Pediatric Neurology

Ayşe Serdaroğlu, Gazi University

Pediatric Neurology

Kıvılcım Gücüyener, Gazi University

Pediatric Neurology


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