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Test Code
DOXEP
Test Name
Doxepin, Quantitative, Whole Blood
CPT Codes
AMA 80335, CMS G0480
Expected Turnaround Time
5 - 7 days
Clinical Utility

Useful in determining the use or abuse of Doxepin.

Testing includes identification and quantitation of:

  • Doxepin
  • n-Desmethyldoxepin (Doxepin Metabolite)
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)

Toxic (ng/mL)

Doxepin + n-Desmethyldoxepin

50-100

>300
Limitations

Analyte

Reporting Limit (ng/mL)

Doxepin

25

n-Desmethyldoxepin

25
Performing Location
Roble Road Core Laboratory
Alternate Names
  • Adapin
  • Sinequan
  • Zonalon
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.
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