Test Details
Methodology
Ultrafiltrate assayed by Immunoassay (IA)
Result Turnaround Time
2 - 4 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
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.
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.
This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration. |
References
Specimen Requirements
Specimen
Serum or plasma
Volume
3 mL
Minimum Volume
1.1 mL
Container
Red-top tube or lavender-top (EDTA) tube. Do not use a gel-barrier tube. The use of gel-barrier tubes is not recommended due to slow absorption of the drug by the gel. Depending on the specimen volume and storage time, the decrease in drug level due to absorption may be clinically significant.
Collection Instructions
Transfer separated serum or plasma to a plastic transport tube.
Stability Requirements
| Temperature | Period |
|---|---|
| Room temperature | 14 days |
| Refrigerated | 14 days |
| Frozen | 14 days |
| Freeze/thaw cycles | Stable x3 |
Reference Range
Therapeutic: 6.0-22.0 μg/mL
Storage Instructions
Room temperature
Causes for Rejection
Gel-barrier tube; hemolysis; serum or plasma not removed from cells
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 070789 | Free Valproic Acid (Depakote) | 4087-3 | 070790 | Free Valproic Acid (Depakote) | ug/mL | 4087-3 |
| Order Code | 070789 | |||||
| Order Code Name | Free Valproic Acid (Depakote) | |||||
| Order Loinc | 4087-3 | |||||
| Result Code | 070790 | |||||
| Result Code Name | Free Valproic Acid (Depakote) | |||||
| UofM | ug/mL | |||||
| Result LOINC | 4087-3 |