Test Code VALPA Valproic Acid, Total, Serum
Reporting Name
Valproic Acid, Tot, SPerforming Laboratory
Mayo Clinic Laboratories in RochesterUseful For
Monitoring total valproic acid in therapy
Assessing compliance
Evaluating potential toxicity
Method Name
Immunoassay
Specimen Required
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 0.5 mL
Collection Instructions:
1. Serum gel tubes should be centrifuged within 2 hours of collection.
2. Red-top tubes should be centrifuged and serum aliquoted into a plastic vial within 2 hours of collection.
Specimen Type
SerumSpecimen Minimum Volume
0.25 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 14 days | |
Frozen | 28 days | ||
Ambient | 72 hours |
Reject Due To
Gross hemolysis | Reject |
Reference Values
Therapeutic: 50 (trough)-125 (peak) mcg/mL
Critical value: ≥151 mcg/mL
Interpretation
The generally acceptable range for total valproic acid used as a reference to guide therapy is 50 to 125 mcg/mL. Peak levels should not exceed 125 mcg/mL.
Because the concentration of valproic acid fluctuates considerably depending on the time from last dose, interpretation of the clinical significance of the valproic acid concentration must take into consideration the timing of the blood specimen. For this reason, 2 collections are sometimes made to assess the trough and peak concentrations.
Day(s) Performed
Monday through Sunday
Report Available
Same day/1 to 2 daysTest Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
80164
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
VALPA | Valproic Acid, Tot, S | 4086-5 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
VALPA | Valproic Acid, Tot, S | 4086-5 |
Forms
If not ordering electronically, complete, print, and send 1 of the following forms with the specimen:
-Neurology Specialty Testing Client Test Request (T732)
-Therapeutics Test Request (T831)