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Test Code FENTX Fentanyl with Metabolite Confirmation, Chain of Custody, Random, Urine

Useful For

Detection and confirmation of illicit drug use involving fentanyl


Chain of custody is required whenever the results of testing could be used in a court of law. Its purpose is to protect the rights of the individual contributing the specimen by demonstrating that it was under the control of personnel involved with testing the specimen at all times; this control implies that the opportunity for specimen tampering would be limited.

Additional Tests

Test ID Reporting Name Available Separately Always Performed
COCH Chain of Custody Processing No Yes
ADLTX Adulterants Survey, CoC, U Yes Yes

Testing Algorithm

Adulterants testing will be performed on all chain of custody urine samples as per regulatory requirements.

Reporting Name

Fentanyl w/metabolite Conf, CoC, U

Specimen Type


Specimen Required

Container/Tube: Chain-of-Custody Kit (T282) containing the specimen containers, seals, and documentation required.

Specimen Volume: 20 mL

Collection Instructions: Collect specimen in the container provided, seal, and submit with the associated documentation to satisfy the legal requirements for chain-of-custody testing.

Additional Information: Submitting <20 mL will compromise our ability to perform all necessary testing.

Specimen Minimum Volume

2.1 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Urine Refrigerated (preferred) 14 days
  Frozen  14 days
  Ambient  72 hours

Reject Due To

All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.

Day(s) and Time(s) Performed

Friday, Varies

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Test Classification

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.

CPT Code Information


G0480 (if appropriate)

LOINC Code Information

Test ID Test Order Name Order LOINC Value
FENTX Fentanyl w/metabolite Conf, CoC, U In Process


Result ID Test Result Name Result LOINC Value
36653 Fentanyl Immunoassay Screen 3637-6
36191 Fentanyl 58381-5
36190 Norfentanyl 58383-1
36192 Fentanyl Interpretation 69050-3
36193 Chain of Custody 77202-0

Reference Values



Cutoff concentrations:

Immunoassay screen

<2 ng/mL


Fentanyl by LC-MS/MS

0.2 ng/mL


Norfentanyl by LC-MS/MS

1.0 ng/mL

Method Name

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


1. Chain-of-Custody Request is included in the Chain-of-Custody Kit (T282).

2. If not ordering electronically, complete, print, and send a Therapeutics Test Request (T831) with the specimen.