Test Code THCM 11-nor-Delta-9-Tetrahydrocannabinol-9-Carboxylic Acid (Carboxy-THC) Confirmation, Meconium
Ordering Guidance
For chain-of-custody testing, order THCMX / 11-nor-Delta-9-Tetrahydrocannabinol-9-Carboxylic Acid (Carboxy-THC) Confirmation, Chain of Custody, Meconium.
Specimen Required
Supplies: Stool container, Small (Random), 4 oz (T288)
Container/Tube: Stool container
Specimen Volume: 1 g (approximately 1 teaspoon)
Collection Instructions: Collect entire random meconium specimen.
Useful For
Detecting in utero drug exposure to marijuana (tetrahydrocannabinol) up to 5 months before birth
Method Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Reporting Name
Carboxy-THC Confirmation, MSpecimen Type
MeconiumSpecimen Minimum Volume
0.3 g (approximately 1/4 teaspoon)
Specimen Stability Information
Specimen Type | Temperature | Time |
---|---|---|
Meconium | Frozen (preferred) | 28 days |
Refrigerated | 21 days | |
Ambient | 14 days |
Reject Due To
Grossly bloody | Reject; Pink OK |
Stool Diapers |
Reject |
Reference Values
Negative
Positives are reported with a quantitative liquid chromatography tandem mass spectrometry result.
Cutoff concentration: 5 ng/g
Day(s) Performed
Monday through Sunday
Report Available
2 to 3 daysPerforming Laboratory

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
G0480
80349 (if appropriate for select payers)
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
THCM | Carboxy-THC Confirmation, M | 69007-3 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
31863 | Carboxy-THC | 69007-3 |
31876 | Interpretation | 69050-3 |
31877 | Chain of Custody | 77202-0 |
Forms
If not ordering electronically, complete, print, and send a Therapeutics Test Request (T831) with the specimen.