ACMT Position Statement: Interpretation of Urine for Tetrahydrocannabinol Metabolites

  • Nicholas Connors
  • Michael J. Kosnett
  • Ken Kulig
  • Lewis S. Nelson
  • Andrew I. StolbachEmail author
Position Statement

The position of the American College of Medical Toxicology (ACMT), endorsed by the American Academy of Clinical Toxicology (AACT), the American Academy of Emergency Medicine (AAEM), the American College of Emergency Physicians (ACEP), and the American Society of Addiction Medicine (ASAM) is as follows:

A positive test for tetrahydrocannabinol (THC) metabolite indirectly indicates that THC, a psychoactive compound in cannabis, has been present in the body. Urine THC metabolite tests are not designed to identify synthetic cannabinoids or CBD. The test results do not identify route of THC exposure, source of exposure, specific timing of exposure, dose, intentional or accidental nature of exposure, or clinical impairment.


Urine cannabinoid testing has been used to improve workplace safety, although the benefit of such testing is not supported for many forensic or clinical applications. Forensic testing refers to application of an assay to answer a legal question; clinical...


Cannabidiol Cannabinoid Drug testing THC Urine tox screen 


Compliance with Ethical Standards


While individual practices may differ, this is the position of the American College of Medical Toxicology at the time written, after a review of the issue and pertinent literature.

Conflict of Interest



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Copyright information

© American College of Medical Toxicology 2020

Authors and Affiliations

  • Nicholas Connors
    • 1
    • 2
  • Michael J. Kosnett
    • 3
  • Ken Kulig
    • 4
  • Lewis S. Nelson
    • 5
  • Andrew I. Stolbach
    • 6
    Email author
  1. 1.Department of Emergency MedicineMedical University of South CarolinaCharlestonUSA
  2. 2.Palmetto Poison CenterColumbiaUSA
  3. 3.University of Colorado School of MedicineAuroraUSA
  4. 4.Toxicology Associates, Prof LLCDenverUSA
  5. 5.Rutgers New Jersey Medical SchoolNewarkUSA
  6. 6.Johns Hopkins University School of MedicineBaltimoreUSA

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