Test Code LAB4220 VALPROIC ACID
Specimen Type
Preferred Sample: Lithium Heparin Plasma (Mint Green Top, Dark Green Top)
Alternative Sample: Serum (SST, Gold, Corvac, Tiger, Red Top Tube)
* See Test Limitations on this page for information about tubes containing gel.
Collection Instructions
Draw just prior to next dose. Note times of dose and drawing.
Specimen Volume
1 mL
Minimum Volume
0.5 mL
Turnaround Time
STAT: 1 hour
Routine: 4 hours
Test Schedule
Daily
Method
Colorimetric
Reference Ranges
Valproic Acid µg/mL (Peak or Trough)
Therapeutic 50-100
Toxic: Greater Than 150
Synonyms
Depakene; Depakote; Divalproex
Test Components
Valproic Acid, µg/mL.
CPT Codes
80164
Test Limitations
Studies have shown that therapeutic drug levels may be altered in serum/plasma that remains in contact with separator gel. Therapeutic drug levels collected in gel tubes (SST or PST) should be run within 4 hrs of collection. If a physician requests, the test will be performed after the recommended 4 hr stability period but a disclaimer will be attached to the result.