Valproic acid

Tube Type

Test ID		LAB24
EPIC Order		VALPROIC ACID LEVEL
CPT Code(s)		80164
Group/Individual Test		Individual
Laboratory		Core Laboratory
Tube Station		Routine: 30; STAT: 888
Specimen	Routine:	2 mL blood/navy blue plain tube/red plain tube also acceptable; See Comments
	Micro:	300 µL blood/red plain (no gel) bullet; See Comments
Stability		Unspun: 24 hours Spun/separated, Room Temperature: 8 hours Spun/separated, Refrigerator: 2 days Spun/separated, Frozen: 30 days
Availability		24 hours/day
Turnaround Time		Routine: 2 hours; STAT: 1 hour
Reference Range	Therapeutic:	50-100 µg/mL (trough, steady state)
	Toxic:	>200 µg/mL
Comments	Collection information: Use trough levels for routine monitoring Collect immediately before next dose Red top tubes must NOT contain Serum Separator Gel Reference Range effective 4-5-2010.

Reviewed by J. Carr on January 09, 2026

UNC Hospitals
McLendon Clinical Laboratories
101 Manning Drive
Chapel Hill, NC 27514