Propoxyphene, Urine Screen with Reflex to Quantitation
Also known as: PPXY RFX U
Use
This test is useful for general screening in contexts of compliance and/or abuse. The initial screening is performed using an immunoassay, which is designed to detect the presence of propoxyphene at or above a certain concentration level. If a presumptive positive result is obtained, confirmation and quantification are performed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). This reflex testing approach ensures more accurate confirmation of propoxyphene exposure.
Special Instructions
Propoxyphene and Metabolite, Urine (3003726) is preferred for follow-up testing in case of presumptive results. Ensure that 4 mL of urine is transferred to a container without preservatives or additives, such as an ARUP Standard Transport Tube.
Limitations
The test is for medical purposes and not valid for forensic use. Positive results may be affected by inappropriate specimen collection timing relative to drug administration, poor drug absorption, or diluted/adulterated urine. It is designed to detect drugs at class-specific concentrations, so limitations may exist in distinguishing between different metabolites or other substances in the same class.
New York Approved
Methodology
Mass Spectrometry
Biomarkers
LOINC Codes
- 19429-0
- 54247-2
Result Turnaround Time
1-8 days
Related Documents
For more information, please review the documents below
Specimen
Urine
Volume
4 mL
Minimum Volume
2 mL
Container
ARUP Standard Transport Tube
Collection Instructions
Collect random urine and transfer to an appropriate container without preservatives.
Causes for Rejection
Breast milk.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 1 week |
| Refrigerated | 1 month |
| Frozen | 1 month |
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