Test Directory

Clear All
Test Code
DIAZP
Test Name
Diazepam, Quantitative, Whole Blood
CPT Codes
AMA 80346, CMS G0480
Expected Turnaround Time
5 - 7 days
Clinical Utility

Identification and quantitation of diazepam and metabolites to monitor therapy or assess toxicity.

Useful in determining the use or abuse of Diazepam.

Testing includes identification and quantitation of:

  • Diazepam
  • Nordiazepam
  • Oxazepam
  • Temazepam
Specimen and Container Info

Specimen

Container

Volume

Whole Blood

Grey Top* (Sodium Fluoride, Potassium Oxalate)

3 mL

Whole Blood

Dark Green Top (Lithium Heparin)

3 mL

Whole Blood

Lavender Top (EDTA)

3 mL

Serum

Red Top, Plain

1 mL

*Preferred Specimen
Processing and Submission Instructions

For forensic or legal purposes, submit specimen in a plastic evidence bag with a Chain-of-Custody Form.
Transport Instructions

Transport to the laboratory refrigerated.
Stability Requirements

Room Temperature

 7 days

Refrigerated

 7 days
Causes for Rejection

Specimens collected in separator tubes will be rejected. 
Methodology
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
Reference Intervals

 Analyte

Therapeutic Range (ng/mL)

Diazepam

100-1000

Nordiazepam

100-1000

 Oxazepam

 200-1400

 Temazepam Peak concentrations

 200-1100

*Steady state concentrations following chronic dosing of 70 mg/day of diazepam : 50-400 ng/ml
Limitations

Analyte

Reporting Limit (ng/mL)

Diazepam

20

Nordiazepam

20

Oxazepam

20

Temazepam

20
Performing Location
Roble Road Core Laboratory
Alternate Names

Diazepam Alternate Names:

  • Valium
  • Diastat
  • Diazepam
  • Nordiazepam

Oxazepam Alternate Names:

  • Serax
  • Oxazepam

Temazepam Alternate Names:

  • Restoril
  • Normison
  • Nortem
  • Temazepam
Testing Schedule
Routine, 2 times per week
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
© 2026 HNL Lab Medicine. All rights reserved.