Test Overview

Test Methodology

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

Test Usage

Assessing toxicity or abuse.

Reference Range*

Propoxyphene: 100 - 400 ng/mL; Norpropoxyphene: 200 - 2200 ng/mL; Propoxyphene + Norpropoxyphene: 400 - 3000 ng/mL.

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

Test Details

Days Test Performed


Analytic Time

7 days

Soft Order Code




Laboratory Reference

Mayo FPPOX (57140) (MedTox 108)

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Specimen Requirements

Offsite Collection Instructions

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

Rejection Criteria

SST or PST tube not acceptable.


Yellow Top Tube
Red Top Tube

Normal Volume

5 mL serum or plasma

Minimum Volume

2 mL serum or plasma

Additional Information

Test sent to Mayo Medical Laboratories; performed by MedTox Laboratories.

Billing Information

Fee Codes

CPT Code


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