Valproic Acid, Free, Serum or Plasma
Also known as: Depacon®, Depakene®, Depakote®, Free Valproic Acid, Stavzor™
Use
Since valproic acid is highly bound, drugs that compete for protein binding sites can increase the amount of free valproic acid (biologically active protein); these include dicumarol, high dose salicylates, and phenylbutazone. If toxicity is suspected, a free valproic acid level should be obtained.
Special Instructions
Testing schedules may vary. The use of gel-barrier tubes is not recommended due to slow absorption of the drug by the gel, which can affect the test results. Depending on the specimen volume and storage time, the decrease in drug level due to absorption may be clinically significant. Transfer separated serum or plasma to a plastic transport tube.
Limitations
This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration. The use of gel-barrier tubes is not recommended because the absorption of valproic acid by the gel may lead to decreased drug levels that are clinically significant.
Methodology
Immunoassay (Other)
Biomarkers
LOINC Codes
- 4087-3
- 4087-3
Result Turnaround Time
2-4 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
3 mL
Minimum Volume
1.1 mL
Container
Red-top tube
Collection Instructions
Transfer separated serum to a plastic transport tube.
Storage Instructions
Room temperature
Causes for Rejection
Gel-barrier tube; hemolysis; serum not removed from cells
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 14 days |
| Refrigerated | 14 days |
| Frozen | 14 days |