Valproic Acid, Free
Depakene®, Depakote®, Valproate, Valproex®
Test Codes
Mayo: VALPF, EPIC: LAB6173, Beaker: XVALF
Department
Send Outs
Specimen Collection Criteria
Collect (preferred specimen): One Gold-top SST tube.
Also acceptable: One plain Red-top tube.
Physician Office/Draw Specimen Preparation
Let specimen clot 30-60 minutes then centrifuge to separate serum from cells within two hours of collection. Transfer serum to a plastic transport tube and refrigerate (2-8°C or 36-46°F).
Preparation for Courier Transport
Transport: 2.0 mL serum, refrigerated (2-8°C or 36-46°F). (Minimum: 1.0 mL)
Rejection Criteria
Specimens not collected and processed as indicated.
In-Lab Processing
Let specimen clot 30-60 minutes then centrifuge to separate serum from cells within two hours of collection. Transfer serum to a plastic transport tube and refrigerate (2-8°C or 36-46°F).
Transport: 2.0 mL serum, refrigerated (2-8°C or 36-46°F). (Minimum: 1.0 mL)
Storage
Specimen Stability for Testing:
Room Temperature (20-26°C or 68-78.8°F): 72 hours
Refrigerated (2-8°C or 36-46°F): 14 days
Frozen (-20°C/-4°F or below): 28 days
Specimen Storage in Department Prior to Disposal:
Specimen retention time is determined by the policy of the reference laboratory. Contact the Send Outs Laboratory with any questions.
Laboratory
Sent to Mayo Clinic Laboratories in Rochester, MN.
Performed
Sunday – Saturday.
Results available within 2-3 days.
Reference Range
By report.
Test Methodology
Ultrafiltration Followed by Immunoassay.
Interpretation
Free valproic acid may be important to monitor in patients with altered or unpredictable protein binding capacity because valproic acid exhibits variable, dose-dependent protein binding. Valproic acid is also subject to drug-drug interactions due to displacement of protein binding. Calculating percent free attempts to minimize differences in assay cross-reactivity and may be useful in dose optimization.
CPT Codes
80165
LOINC: 4087-3, Last Dose Date 29742-4, Last Dose Time 29637-6
Contacts
Send Outs Laboratory – RO
248-551-9045
Name: Send Outs Laboratory – RO
Location:
Phone: 248-551-9045
Last Updated
7/19/2021
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