Test Code VALPF 
Test VALPROIC ACID, FREE (MMC Inpatient Only) 
Methodology Fluorescence Polarization 
Description Valproic Acid (dipropylactic acid) is primarily used in the treatment of petit mal seizures and other generalized and partial complex seizures. Due to the potential of severe adverse reactions, it is important that levels of valproic acid be monitored during therapy. A branched chain fatty acid, over 90% of valproic acid is protein bound, mainly to albumin. Numerous factors, including serum albumin levels, total drug concentration, free fatty acid levels, multi-drug usage and various physiological conditions, significantly influence this binding. The result is considerable inter - and - inrtra individual variation in the free (unbound) biologically active fraction of valproic acid. For these reasons, it has been concluded that monitoring free valproic acid is justified and may even be the method of choice under all circumstances. 
Specimen 2 mLs of serum or plasma
Serum - Red Top Tube or Gold Top Tube (SST)
Plasma - Lithium Hepatin Tube 
Reference Values Therapeutic Range: 5-25 ug/mL 
Analytic Time 1 Day, Vailable STAT 
Day(s) Test Set Up Monday through Sunday 
CPT Code(s) 80165