Days Set Up
Thursday
Analytic Time

4 hours

MiChart Code
Doxepin and Desmethyldoxepin Level
Soft Order Code
DXPN

Test Updated:

Synonyms

Adapin
Sinequan
Tricyclics, Doxepin
DOXEPIN AND DEMETHYLDOXEPIN
DEDOX
DOX
Doxepin and Nordoxepin
DEMETHYLDOXEPIN
DOXEPIN
DOXEPIN RESULT
DOXEPIN & DEMETHYLDOXEPIN LEV
DOXEPIN + DEMETHYLDOXEPIN LEV

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Find a Requisition

All specimens should be accompanied by a requisition.

Submitting Specimens

Learn about how to properly label and where to ship specimens.

Order Kits and Supplies

MLabs provides all the supplies necessary for the collection of specimens.

Test FAQ

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Test Overview

Test Methodology

Liquid Chromatography - Tandem Mass Spectrometry (LC-MS/MS)

Test Usage

Monitor therapeutic drug levels; monitor patient compliance; evaluate doxepin toxicity

Reference Range

Therapeutic: 75-200 ng/mL; Toxic: > 500 ng/mL; Lethal: 1000 ng/mL (sum of Doxepin and Desmethyldoxepin).

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Specimen Requirements

Offsite Collection Instructions

Collect blood in a red top or green top tube; do not use SST tube. Centrifuge, aliquot serum or plasma into plastic vial as soon as possible and refrigerate.

Red Top Tube
Normal Volume
1 mL serum or plasma
Minimum Volume
0.7 mL serum or plasma

Billing Information

CPT Code
80335
Pro Fee Code
 
LOINC
Z134-7

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Our High Standard

Quality that sets us apart

As the reference laboratory division of Michigan Medicine's Department of Pathology, MLabs shares the institution's commitment to applying established quality principles to clinical laboratory testing. Like other large organizations in complex, consequential fields, we rely on an established approach to monitor quality throughout the testing process.