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HelpTest Code THCU Delta-8 and Delta-9-Carboxy-Tetrahydrocannabinol (THC) Confirmation, Random, Urine
Reporting Name
Carboxy-THC Confirmation, UUseful For
Detection and confirmation of drug use of cannabis/marijuana and to specifically identify and quantify delta-8-carboxy tetrahydrocannabinol (THC-COOH) and delta-9-THC-COOH
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Specimen Type
UrineOrdering Guidance
For situations where chain of custody is required, a Chain-of-Custody Kit (T282) is available. For chain-of-custody testing, order THCX / Delta-8 and Delta-9-Carboxy-Tetrahydrocannabinol (THC) Confirmation, Chain of Custody, Random, Urine
Additional drug panels and specific requests are available. Call 800-533-1710 or 507-266-5700.
Additional Testing Requirements
If urine creatinine is required or adulteration of the sample is suspected, order, ADULT / Adulterants Survey, Random, Urine.
Specimen Required
Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
Collection Container Tube: Plastic urine container
Submission Container/Tube: Plastic, 5-mL tube
Specimen Volume: 3 mL
Collection Instructions:
1. Collect a random urine specimen.
2. No preservative.
Additional Information:
1. No specimen substitutions.
2. STAT requests are not accepted for this test.
Specimen Minimum Volume
0.5 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Urine | Refrigerated (preferred) | 14 days | |
| Frozen | 14 days | ||
| Ambient | 72 hours |
Reference Values
Not Detected
Cutoff concentration:
DELTA-8 CARBOXY-TETRAHYDROCANNABINOL (THC) by LC-MS/MS: <5.0 ng/mL
DELTA-9 CARBOXY-TETRAHYDROCANNABINOL (THC) by LC-MS/MS: <5.0 ng/mL
Day(s) Performed
Monday through Friday
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
80349
G0480 (if appropriate)
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| THCU | Carboxy-THC Confirmation, U | 20521-1 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 618770 | Delta-8 Carboxy-Tetrahydrocannabinol by LC-MS/MS | 20521-1 |
| 2497 | Delta-9 Carboxy-Tetrahydrocannabinol by LC-MS/MS | 20521-1 |
| 21186 | Carboxy-THC Interpretation | 69050-3 |
Clinical Information
There are over 100 different cannabinoids in cannabis/marijuana. The main psychoactive cannabinoid is delta-9-tetrahydrocannabinol (delta-9-THC), which is the active agent of the popularly abused street drug, cannabis/marijuana. Delta-8 tetrahydrocannabinol (delta-8 THC) is another psychoactive substance found in the Cannabis sativa plant, of which cannabis/marijuana and hemp are 2 varieties. Delta-8 THC is one of over 100 cannabinoids produced naturally by the cannabis plant but is not typically found in significant amounts in the plant itself. As a result, concentrated amounts of delta-8 THC are typically manufactured from hemp-derived cannabidiol.
Following consumption of cannabis/marijuana, delta-9-THC metabolizes to a variety of inactive products, one of them being the carboxy metabolite (delta-9-THC-COOH). In almost all medico-legal cases or when the patient adamantly denies cannabis/marijuana use and the immunoassay test is positive, confirmation of the result by a definitive test is required. This test is a definitive, confirmatory test using liquid chromatography tandem mass spectrometry to identify and quantify delta-8-THC-COOH and delta-9 THC-COOH.
Interpretation
The presence of delta-8 and/or delta-9 carboxy tetrahydrocannabinol (THC-COOH) in urine is a strong indicator that the patient has used cannabis/marijuana.
THC-COOH has a long half-life and can be detected in urine for more than 7 days after a single use.
Chronic use causes accumulation of THC and THC-COOH in adipose tissue, such that it is excreted into the urine for as long as 30 to 60 days from the time chronic use is halted.
Report Available
3 to 5 daysSpecimen Retention Time
2 weeksReject Due To
| Gross hemolysis | OK |
| Gross icterus | Reject |
Method Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Forms
If not ordering electronically, complete, print, and send 1 of the following forms with the specimen:
-General Request (T239)
-Therapeutics Test Request (T831)