Cannabinoid Mass Concentration in Urine (24-Hour Collection)
This test measures the presence of cannabinoids, the active compounds found in marijuana, in your urine over a 24-hour period. It helps detect recent marijuana use.
["Detects recent marijuana use via urine cannabinoid levels over a full day."]
Key facts at a glance
- LOINC
- 50338-3
- Short code
- CANNDF
- Synonyms
- Cannabinoids Dial fld-mCnc
- Category
- chemistry
- Sample
- serum
- Container
- Sterile, leak-proof specimen container; red-top tube or specific drug-of-abuse testing container without preservatives
- Units
- N/A
- Ref low
- 0
- Ref high
- 50
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 18 years
- Method
- Immunoassay (screening) with Gas Chromatography-Mass Spectrometry (GC-MS) or Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) for confirmation
- CPT
- 80349
- SNOMED
- 44608003
- Specimen volume
- 10-20 mL of dialysis fluid
- Stability
- Refrigerated (2-8°C): 7 days; Frozen (-20°C or below): 30 days for confirmation testing. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 24–72 hours
- Order
- routine
Why This Test Is Done
Your healthcare provider may order this test if you have concerns about marijuana use, are part of a substance abuse evaluation, or are required for employment, legal, or insurance reasons. It can also be used to monitor ongoing use or treatment progress.
What to Expect Before the Test
You’ll collect all urine produced in a 24-hour period in a special container. Follow instructions carefully to ensure accurate results, such as timing your collection and keeping the sample refrigerated until sent to the lab.
What the Results Mean
Positive results indicate recent marijuana use, while negative results suggest no detectable cannabinoids were present. However, results can vary based on metabolism, frequency of use, and other factors.
Common Causes of Abnormal Results
False positives may occur if you’ve recently used other substances (e.g., hemp products) or if the sample was improperly handled. False negatives can happen if use was very recent or if the collection period was incomplete.
Reference range
Negative (cutoff: typically 50 ng/mL for screening, 15 ng/mL for confirmation by GC-MS/LC-MS/MS). Results should be interpreted in the context of clinical findings.N/A
No special preparation required. Specimen should be collected prior to dialysis session changes or as clinically indicated. Patient consent may be required based on institutional policy.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
Urine Cannabinoid Screen
Frequently asked questions
How long does it take to get results?
Can I drink alcohol before this test?
Does this test detect other drugs besides marijuana?
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 16, 2026. · Read our editorial policy