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Cannabinoid Screening and Confirmation Panel (Serum/Plasma)

Published: August 9, 2026Updated: August 16, 2026

This test measures the presence of cannabinoids, the active compounds found in cannabis, in your blood or plasma. It helps detect recent use and can be used for screening or confirmation purposes.

Quick summary

["This test helps determine if cannabinoids have entered your system, often used in medical, legal, or workplace settings."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
19291-4
Short code
THCSC
Synonyms
Cannabinoids CtO Ur Scn-mCnc
Category
chemistry
Sample
urine
Container
Sterile, leak-proof urine collection container without preservatives; clinical specimen. For forensic testing, use tamper-evident chain-of-custody container.
Units
N/A
Ref low
0
Ref high
49
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
screen
CPT
80307
SNOMED
271280006
Specimen volume
30-50 mL (minimum 10 mL for screening)
Stability
Refrigerated (2-8°C): up to 7 days. Frozen (-20°C or below): up to 1 month or longer for forensic specimens. Room temperature (15-25°C): up to 2-3 days. Avoid repeated freeze-thaw cycles.
Hemolysis max
0
Lipemia max
0
Icterus max
0
TAT
1–24 hours
Order
routine

Why This Test Is Done

Doctors may order this test if you’ve been suspected of using cannabis recently, if you’re undergoing treatment for a condition affected by cannabinoids, or if you’re required for employment, legal, or safety reasons. It can also help monitor long-term use or assess impairment.

What to Expect Before the Test

No special preparation is needed, but you may be asked to fast for a few hours if blood is drawn. If you’re taking medications, let your provider know. For urine tests, avoid certain foods or supplements that could affect results.

How the Test Works

The test uses advanced laboratory techniques, such as high-performance liquid chromatography (HPLC) or immunoassay, to detect cannabinoid compounds in your blood, plasma, or urine. It screens for common cannabinoids like THC (tetrahydrocannabinol) and its metabolites.

What the Results Mean

Results are qualitative (positive/negative) for screening and may include confirmation for specific cannabinoids. Positive results indicate recent cannabis use, but they don’t confirm the exact amount or duration. Follow-up testing may be needed for further details.

Reference range

Cutoff: 50 ng/mL. Negative: <50 ng/mL THC-COOH. Positive: ≥50 ng/mL THC-COOH. This is a screening test; positive results should be confirmed by GC-MS or LC-MS/MS.N/A

Specimen: urine

No special preparation required. Patient should be informed that adulteration, dilution, or substitution of urine specimen may invalidate results. Collect under chain-of-custody protocol when required for forensic or workplace testing.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Cannabinoid testing is critical in identifying substance use disorders, guiding treatment plans, and ensuring workplace safety. It also plays a role in legal proceedings, medical evaluations, and research. However, results should be interpreted alongside clinical context, as cannabinoids can affect mood, coordination, and health.

Short name

Cannabinoid Panel

Frequently asked questions

What Does a Positive Result Mean?
A positive result means cannabinoids were detected in your sample, suggesting recent cannabis exposure. This could be from smoking, vaping, or other consumption methods. It doesn’t indicate how long you’ve been using or the exact amount.
Can Cannabinoids Affect My Driving or Work Performance?
Yes, cannabinoids can impair judgment, reaction time, and coordination, even if you’re not high. Some employers or legal systems use these tests to assess impairment, so results may impact your ability to drive, work, or participate in certain activities.
How Long Do Cannabinoids Stay in My System?
Detection depends on the type of sample and how frequently you use cannabis. THC metabolites can be detected in blood for days to weeks, in urine for weeks to months, and in saliva for hours to days. Results vary by individual metabolism and usage patterns.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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