Update Type: Reference range changed
Test Updated: 08/25/2021
Test Overview
Test Methodology

Homogeneous Enzyme Immunoassay

Test Usage

Monitor therapeutic drug level, compliance, evaluate valproic acid toxicity

Reference Range *

5 - 25 mcg/mL (approximately 10% of the total drug concentration); Toxic >30 mcg/mL.

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Limitations

Use of heparinized blood tubes is not allowed (may lead to artificially high free valproic acid level).

Test Details
Days Set Up
Daily, 24 hrs
Analytic Time

2 hours

Soft Order Code
FVALP
MiChart Code
Valproic Acid Level, Free
Synonyms
  • Depakene
  • Depakene, Protein Free
  • FVALP
  • Free Depakene
  • Free Valproic Acid
Laboratory
Chemical Pathology
Section
Automation
Specimen Requirements
Collection Instructions

Collect blood in a red top tube. Centrifuge, aliquot serum into a plastic vial, and refrigerate.

Alternate Specimen
SST tube
Normal Volume
1 mL serum or plasma
Minimum Volume
0.75 mL serum or plasma
Rejection Criteria
Heparinized samples
Billing
CPT Code
80165
Fee Code
33202
LOINC
4087-3