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HelpTest ID THCU Carboxy-Tetrahydrocannabinol (THC) Confirmation, Urine
Useful For
Detection and confirmation of drug abuse involving delta-9-tetrahydrocannabinol (marijuana)
Method Name
Gas Chromatography-Mass Spectrometry (GC-MS) Confirmation with Quantitation
Reporting Name
Carboxy-THC Confirmation, USpecimen Type
UrineCollection Container Tube: Plastic urine container
Submission Container/Tube: Plastic, 60-mL urine bottle
Specimen Volume: 20 mL
Collection Instructions:
1. Collect a random urine specimen.
2. Submit 20 mL in 1 plastic bottle.
3. No preservative.
Additional Information:
1. No specimen substitutions.
2. No STATS are accepted for this procedure.
3. For situations where chain of custody is required, a Chain-of-Custody Kit (T282) is available. For chain-of-custody testing, order THCX / Carboxy-THC Confirmation, Chain of Custody, Urine.
4. Additional drug panels and specific requests are available. Call Mayo Medical Laboratories at 800-533-1710 or 507-266-5700.
5. If urine creatinine is required or adulteration of the sample is suspected, the following test should be requested, ADULT / Adulterants Survey, Urine. For additional information, please refer to ADULT / Adulterants Survey, Urine.
6. Submitting less than 20 mL will compromise our ability to perform all necessary testing.
Forms: Chain-of-Custody Request Form is included in the Chain-of-Custody Kit (T282). A copy of this form is also available at http://www.mayomedicallaboratories.com/it-mmfiles/chain-of-custody-request-form.pdf.
Specimen Minimum Volume
5 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Urine | Refrigerated (preferred) | 14 days |
| Frozen | 14 days | |
| Ambient | 72 hours |
Clinical Information
Delta-9-tetrahydrocannabinol is the active agent of the popularly abused street drug, marijuana.
Following consumption of the drug, either by inhalation or ingestion, it is metabolized to a variety of inactive chemicals, one of them being delta-9-tetrahydrocannabinol carboxylic acid.
The immunochemical procedure used to screen for tetrahydrocannabinol (THC) as part of IDOAU / Drug Abuse Survey, Urine is designed to cross-react with THC carboxylic acid.
In almost all medico-legal cases and in screening of employees, or when the patient adamantly denies THC use and the immunochemical test is positive, confirmation of the result by gas chromatography-mass spectrometry (GC-MS) and EIA are required.
Reference Values
Negative
Cutoff concentration:
Carboxy-THC- by GC/MS <3.0 ng/mL
Cautions
No significant cautionary statements
Day(s) Performed
Monday through Friday
Report Available
2 daysPerforming Laboratory
Mayo Medical 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
80349
G0480 (if appropriate)