A case of valproate-induced hyperammonemia due to carnitine deficiency who responded well to levocarnitine therapy

Abstract

A 75-year-old male who was diagnosed as epilepsy in 1958 and started antiepileptic drugs containing valproic acid. γ-GTP high level and hyperammonemia were pointed out in 2011. No data or findings suggesting liver cirrhosis were observed with blood test, abdominal echo, abdominal contrast CT. Carnitine showed a markedly low value. He was diagnosed with hyperammonemia secondary to carnitine deficiency due to valproic acid therapy. Improvement of serum carnitine concentration, blood ammonia level and subjective symptoms was observed after the administration of levocarnitine. In the case of valproic acid administration, hyperammonemia should be noted and carnitine is needed to be measured to judge adaptation of carnitine replacement therapy.