Encephalopathy and myoclonus triggered by valproic acid.
In recent years, the use of valproic acid (VPA) as a mood-stabilizing agent has continuously increased. Although VPA usually is well tolerated, its use in combination with other psychotropic compounds might bear an elevated risk of adverse reactions. Here, we present the case of a 42-year-old male suffering from treatment-resistant psychotic depression, who was prescribed VPA additionally to lithium, clomipramine, flupentixol and risperidone. By doing so, he developed myoclonus, tremor and encephalopathy with sedation and marked EEG background slowing. Most notably, these side effects occurred in the presence of normal VPA and ammonia serum concentrations. On VPA discontinuation, all symptoms vanished and EEG normalized. We thus suggest that direct VPA-induced encephalopathy in the absence of ammonemia does exist, in this case probably facilitated by psychotropic polypharmacy.
Reif
Andreas
A
Department of Psychiatry, Julius-Maximilians-University of Würzburg, Füchsleinstr. 15, D-97080 Würzburg, Germany. a.reif@gmx.net
Leonhard
Christine
C
Mössner
Rainald
R
Lesch
Klaus-Peter
KP
Fallgatter
Andreas J
AJ
D000328:Adult; D018692:Antimanic Agents / Q000009:adverse effects*; D001927:Brain Diseases / Q000139:chemically induced* / Q000503:physiopathology; D004569:Electroencephalography / Q000187:drug effects; D006801:Humans; D008297:Male; D009207:Myoclonus / Q000139:chemically induced* / Q000503:physiopathology; D014635:Valproic Acid / Q000009:adverse effects*
D018692:Antimanic Agents; D014635:Valproic Acid