Accurately characterize marijuana use through urine THC testing

Test in Focus

Mayo Clinic Laboratories’ new marijuana monitoring evaluation not only detects the metabolite of delta-9 tetrahydrocannabinol (THC), which is the most prominent psychoactive compound found in marijuana, but also for the metabolite of delta-8 THC. Delta-8 THC, also psychoactive, has grown in popularity in recent years. In this test-specific episode of the "Answers From the Lab" podcast, Paul Jannetto, Ph.D., and Loralie Langman, Ph.D., discuss how this innovative assay can clarify and characterize patients’ marijuana use.

“Delta-8 carboxy THC is the unique metabolite of delta-8 THC, which naturally exists in the cannabis plant in very small quantities, and it only has about half of the psychoactivity as delta-9-THC." "However, we're now seeing delta-8 THC containing products appearing in both marijuana and hemp marketplaces. The legal status of delta-8 THC actually varies across the United States, so it actually may be legal in some states if it's derived from hemp. Therefore, it's really important for laboratory assays to be able to identify both the delta-8 and the delta-9 carboxy THC metabolites.”

Testing to accurately identify both delta-8 and delta-9 carboxy THC metabolites can be useful for a number of reasons, including monitoring patients enrolled in addiction rehabilitation programs and determining the cause of adverse, drug-related medical events.

“Because we have the ability to test for both substances…patients who might be saying, Well, most of the assays only pick up the delta-9, so I'm going to use the delta-8 because I won't get caught, we have the ability to pick them both up,” Dr. Langman says. “And I think that gives us an advantage.”

Listen to learn about other advantages of Mayo Clinic Laboratories’ marijuana testing.

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Useful information

Detection and confirmation of drug use of cannabis/marijuana and will specifically identify and quantify delta-8-THC-COOH and delta-9-THC-COOH.

Specimen requirements

  • Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
  • Collection Container Tube: Plastic urine container
  • Submission Container/Tube: Plastic, 5-mL tube
  • Specimen Volume: 3 mL
  • Specimen Minimum Volume: .5 mL

Collection Instructions:

  1. Collect a random urine specimen.
  2. No preservative.

Additional Information:

  1. No specimen substitutions.
  2. STAT requests are not accepted for this test.

Performance information

Analytic time: 3 to 5 days

Days performed: Monday through Friday

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Robin Huiras-Carlson

Robin Huiras-Carlson is a senior marketing specialist at Mayo Clinic Laboratories and a Mayo Clinic employee since 2015. Her writing focuses on specialty testing, innovation, and patient-focused initiatives.