Protein binding of valproic acid in uremic patients

Protein binding of valproic acid was studied in four uremic patients on long-term hemodialysis. Before dialysis, the free fraction was 0.31 +/- 0.11 (SD); this was larger than in nonuremic subjects. During hemodialysis, the free fraction increased significantly (p less than 0.01) in three patients (mean, 0.64 +/- 0.32 SD).