Successful treatment of valproic acid overdose with hemodialysis

A 43-year-old woman took a large amount of depakote (divalproex, a slow-rel ease form of valproate), became comatose, and developed severe hypotension refractory to fluid resuscitation and high dose vasopressors. The serum val proic acid (VPA) concentration on admission was 1,380 mu g/mL (therapeutic range, 50 to 100 mu g/mL). She also had metabolic acidosis, thrombocytopeni a, and normal renal and liver functions. Hemodialysis was initiated 4 hours after presentation, After 6 hours of hemodialysis with a high-flux dialyze r, her serum VPA concentration decreased from 940 mu g/mL to 164 mu g/mL, c oincident with improvement in clinical status. The half-life of VPA was red uced to 2.4 hours with hemodialysis, whereas it was 7.2 hours before the pr ocedure. Hemodialysis could be a valuable therapeutic intervention in VPA t oxicity. (C) 1999 by the National Kidney Foundation, Inc.