PT  - JOURNAL ARTICLE
AU  - Wyllie, Elaine
AU  - Wyllie, Robert
AU  - Rothner, A. David
AU  - Erenberg, Gerald
AU  - Cruse, Robert P.
TI  - Valproate-induced hyperammonemia in asymptomatic children
DP  - 1983 Sep 21
TA  - Cleveland Clinic Journal of Medicine
PG  - 275--277
VI  - 50
IP  - 3
4099  - http://www.ccjm.org/content/50/3/275.short
4100  - http://www.ccjm.org/content/50/3/275.full
SO  - Cleve Clin J Med1983 Sep 21; 50
AB  - Since its introduction in the United States in 1978 for treatment of seizure disorders, valproic acid (VPA) has been associated with hepatic dysfunction. Patients who received VPA have developed a spectrum of toxicity from fulminant hepatic failure to lethargy with elevated serum ammonia levels and normal transaminase. To determine the frequency of hyperammonemia, venous ammonia levels were obtained in three groups of asymptomatic patients: 16 receiving VPA only, 40 receiving VPA plus other anticonvulsants, and 32 control patients receiving a variety of other seizure medications. Seventy-three percent of patients receiving VPA had elevated serum ammonia levels greater than 45 Mg/dl compared to 28% of the control group (p < 0.0001). In 88% of the patients receiving VPA, the serum VPA level was <110 gg/ml (therapeutic range, 50-100 gg/ml), and all VPA levels were <168 gg/ml. There was no correlation between serum VPA levels and ammonia levels. Patients receiving VPA demonstrated hyperammonemia more frequently than did the control group, regardless of the concurrent use of additional anticonvulsants.