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Test Code 2383 Valproic Acid, Plasma

Performing Laboratory

Barnes-Jewish Hospital Laboratory


Enzyme Immunoassay

Literature References:

Package Insert: valproic Acid VALP. Roche Corporation 03/2012

Specimen Requirements

Specimen Type: Plasma
Container/Tube: Mint-green top (lithium heparin)
Specimen Volume: Full tube

Collection Instructions: Draw specimen no earlier than 60 minutes prior to dose. Since absorption is complete by 4 hours, a specimen drawn 4 hours or more after last dose is acceptable.

Day(s) Test Set Up

Monday through Sunday

Turnaround Time:
STAT: 1 hour after receipt in laboratory 
Routine: 2-4 hours after receipt in laboratory

Reference Values

Therapeutic range: 50-100 mcg/mL
Critical result (automatic call-back): ≥200 mcg/mL
Therapeutic or toxic effects of anticonvulsant drugs may occur at different concentrations in different patients and the correlation between dose and clinical effect must be evaluated individually.

Literature References:

Waldman SA, Terzic A. Pharmacology and therapeutics, principles to practice. Saunders Elsevier, Philadelphia, PA, 2009.

Test Classification and CPT Coding


Additional Information

For BJH Laboratory Use Only

Alternate Tube(s):

1 dark green-top (lithium or sodium heparin) tube

1 plain, red-top tube
Separator gel tube is acceptable

Analyte Stability:

Ambient: 2 days

2° C to 8° C: 7 days

≤-20° C: >24 hours

Laboratory Processing Instructions:

Test performed in BJH Core Lab.  Processed by automated line for delivery to the Cobas 8000. Completed specimens are stored refrigerated for 5 days.

Specimen Transport Temperature


LOINC Code Information

Name LOINC Code
Valproic Acid, Plasma 4086-5