Cannabinoid Mass Concentration in Serum or Plasma
This test measures the amount of cannabinoids (active compounds from cannabis) in your blood, often checked for drug screening or monitoring.
["This test helps determine if cannabinoids are present in your system, useful for medical or legal purposes."]
Key facts at a glance
- LOINC
- 26856-5
- Short code
- CANST
- Synonyms
- Cannabinoids Stl-mCnt
- Category
- chemistry
- Sample
- stool
- Container
- Clean, dry, leak-proof stool specimen container with screw-cap lid; sterile wide-mouth container preferred.
- Units
- N/A
- Ref low
- 0
- Ref high
- 10
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- Gas Chromatography-Mass Spectrometry (GC-MS) or Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
- CPT
- 80307
- SNOMED
- 314529007
- Specimen volume
- 5-10 grams of stool (approximately 1-2 tablespoons)
- Stability
- Refrigerated (2-8°C): up to 7 days. Frozen (-20°C or below): up to 30 days for extended storage. Room temperature: not recommended beyond 24 hours.
- TAT
- 48–96 hours
- Order
- routine
Why This Test Might Be Ordered
Your healthcare provider may order this test if you’ve been suspected of using cannabis, if you’re undergoing treatment for a condition influenced by cannabinoids, or if you’re required for employment, legal, or insurance reasons. It can also help monitor long-term use or withdrawal symptoms.
What to Expect Before the Test
No special preparation is usually needed. You may be asked to fast for 8–12 hours before the test if your blood is drawn early in the morning. Bring a list of medications you’re taking, as some may affect results.
What Happens During the Test
A healthcare professional will collect a blood sample from a vein in your arm. The blood is then sent to a lab for analysis using a specialized technique (likely high-performance liquid chromatography or immunoassay).
What the Results Mean
Results are reported as mass concentration (e.g., micrograms per milliliter). A positive result indicates cannabinoids are present, but interpretation depends on context (e.g., recent use vs. chronic exposure).
Reference range
Negative. Cutoff concentration varies by laboratory; typically <10 ng/g for THC metabolites in stool.N/A
No special preparation required. Patient should collect a random stool specimen in a clean, dry container. Avoid contamination with urine or water.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Cannabinoid Level
Frequently asked questions
How long does it take to get results?
Can diet or medications affect cannabinoid test results?
Is this test the same as a urine drug screen?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 15, 2026. · Read our editorial policy