Delta-9-Carboxy-Tetrahydrocannabinol Confirmation and Creatinine Ratio, Random, Urine
Use
Measuring the delta-9 carboxy-tetrahydrocannabinol to creatinine ratio is useful for determining if a patient has used cannabis/marijuana. The presence of delta-9-THC-COOH is a strong indicator of cannabis/marijuana use. However, increases in urine concentrations due to changes in urinary output can be mistaken for new drug use, rather than carryover from previous exposure. Monitoring delta-9-THC-COOH/creatinine ratios over time helps discern new cannabis/marijuana use episodes.
Special Instructions
This test is only orderable as part of a profile. No specimen substitutions are accepted. STAT requests are not accepted for this test.
Limitations
Urine analysis can confirm cannabis/marijuana abstinence. However, if the concentration of delta-9-THC-COOH increases due to hydration changes, it may be misinterpreted as new drug use. Accurate determination of new use requires comparing creatinine-normalized delta-9-THC-COOH concentrations from at least two urine specimens collected between 1-7 days apart. Ratios that exceed certain thresholds indicate new use.
Methodology
Mass Spectrometry (LC-MS/MS)
Biomarkers
LOINC Codes
- 19055-3
- 20521-1
- 69050-3
- 19055-3
Result Turnaround Time
3-5 days
Related Documents
For more information, please review the documents below
Specimen
Urine
Volume
3 mL
Minimum Volume
0.5 mL
Container
Plastic urine container
Collection Instructions
Collect a random urine specimen. No preservative.
Causes for Rejection
Gross icterus
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours |
| Refrigerated | 14 days |
| Frozen | 14 days |
