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Test ID 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.

Method Name

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

Reporting Name

Fentanyl w/metabolite Conf, CoC, U

Specimen Type


Ordering Guidance

For monitoring therapeutic drug levels, order FENTS / Fentanyl, Serum.

Specimen Required

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

Specimen Volume: 5 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 less than 5 mL will compromise the ability to perform all necessary testing.

Specimen Minimum Volume

1 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Urine Refrigerated (preferred) 28 days
  Frozen  28 days
  Ambient  21 days

Reference Values



Cutoff concentrations:

Immunoassay screen

<2 ng/mL


Fentanyl by liquid chromatography-tandem mass spectrometry (LC-MS/MS)

0.2 ng/mL


Norfentanyl by LC-MS/MS

1.0 ng/mL

Day(s) Performed

Tuesday, Thursday, Sunday

Performing Laboratory

Mayo Clinic Laboratories in Rochester

CPT Code Information


G0480 (if appropriate)

LOINC Code Information

Test ID Test Order Name Order LOINC Value
FENTX Fentanyl w/metabolite Conf, CoC, U 67822-7


Result ID Test Result Name Result LOINC Value
36653 Fentanyl Immunoassay Screen 59673-4
36191 Fentanyl by LC-MS/MS 58381-5
36190 Norfentanyl by LC-MS/MS 58383-1
36192 Fentanyl Interpretation 69050-3
36193 Chain of Custody 77202-0

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 US Food and Drug Administration.

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.

Report Available

4 to 6 days

NY State Approved



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.