Phenobarbital

Message

Important Note

Sample must be centrifuged and separated within 1 hour of collection

Test Code

PHENB

Alias/See Also

Epic: LAB30

Barbita (Phenobarbital)
Luminal
PBR
Solfoton (Phenobarbital)

Preferred Specimen

Specimen Type: Serum
Collection Container: Serum gel
Specimen Volume: 3 mL

Minimum Volume

0.5 mL

Other Acceptable Specimens

Collection Container: Red top

Instructions

Centrifuge and separate cells after clot formation and within 1 hour of collection.

Additional Information

The patient's clinical condition and dosage regiment may influence the sample collection time.

Transport Container

Plastic vial

Specimen Stability

Room temperature: 2 days
Refrigerated: 8 days
Frozen: 6 months

Methodology

Chemiluminescent Microparticle Immunoassay (CMIA)

Setup Schedule

Daily

Report Available

Same day

Reference Range

Therapeutic: 15.0 - 40.0 µg/mL

Clinical Significance

Phenobarbital was introduced in 1912 for the treatment of epilepsy, particularly for controlling focal motor or sensory seizures and grand mal seizures. Phenobarbital is bound to both plasma and tissue proteins. Monitoring serum concentrations of Phenobarbital has been shown to improve patient therapy by providing physicians with a tool for adjusting dosage. In addition, because of the narrow therapeutic index and wide inter-individual variability in the rate of phenobarbital metabolism and clearance, the determination of blood levels of phenobarbital for patients receiving therapy is essential.

Performing Laboratory

Inova Laboratories

2832 Juniper Street

Fairfax, VA 22031

Last Updated: April 14, 2023
Last Review: N. Wolford, April 14, 2023

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.