Lab Test

Pentobarbital Level


Test Codes

Antrim #17010, EPIC: LAB5408, SOFT: PENTO

Specimen Collection Criteria

Collect: One plain Red-top tube. (Minimum Whole Blood: 2.0 mL)

See Minimum Pediatric Specimen Requirements for Microtainer® collection.
Do not use Serum Separator Tubes.
Record the exact time of specimen collection on the tube or in the computer system.

Physician Office/Draw Specimen Preparation

Let specimens clot 30-60 minutes. Centrifuge specimen to separate serum from cells. Refrigerate (2-8°C or 36-46°F) the centrifuged collection tube within two hours of collection. (Minimum: 1.0 mL serum)

Preparation for Courier Transport

Transport: Centrifuged collection tube, refrigerated (2-8°C or 36-46°F). (Minimum: 1.0 mL serum)

Rejection Criteria

  • Serum Separator (SST) tubes.
  • Severely lipemic or hemolyzed specimens.  

In-Lab Processing

Let specimens clot 30-60 minutes. Centrifuge specimen to separate serum from cells. Deliver immediately to the appropriate testing station.


Specimen Stability for Testing:

Room Temperature (20-26°C or 68-78.8°F): 24 hours
Refrigerated (2-8°C or 36-46°F): 7 days
Frozen (-20°C/-4°F or below): 3 months

Specimen Storage in Department Prior to Disposal:

Frozen (-20°C/-4°F or below): 2 months


Royal Oak Toxicology Laboratory


Sunday – Saturday, 24 hours a day.
STAT results available within 2 hours of receipt in the Laboratory.
Routine results available within 24 hours. 

Reference Range

Therapeutic Range: 1-5 mcg/mL. 
Critical: Greater than 20 mcg/mL.

For pentobarbital coma or decreasing intracranial pressure:
Therapeutic Range: 30-45 mcg/mL.
Critical: Greater than 60 mcg/mL.

Test Methodology

Liquid Chromatography/ Tandem Mass Spectrometry

This test was developed and its performance characteristics determined by Beaumont Health. It has not been cleared or approved by the FDA. The Laboratory is regulated under CLIA as qualified to perform high-complexity testing. This test is used for clinical purposes and should not be regarded as investigational or for research.


Barbiturates are respiratory depressants and serum levels above the therapeutic range may indicate toxicity.

Clinical Utility

This assay is used to monitor the therapeutic drug level and evaluate the toxicity of pentobarbital. Pentobarbital is a short-acting barbiturate used as a sedative, hypnotic for the short-term treatment of insomnia, as a preanesthetic, and as an anticonvulsant in the emergency control of certain acute convulsive episodes.

CPT Codes

80345 (alternate: G0480).


Last Updated


Microtainer® and Vacutainer® are registered trademarks of Becton, Dickinson and Company.
UroVysion® is a registered trademark of Abbott Laboratories. ThinPrep® is a registered trademark of Hologic, Incorporated.


This directory currently reflects information only for specimens collected and/or processed at the
Farmington Hills, Grosse Pointe, Royal Oak, and Troy campuses.