In 2016, a team of researchers working for Zynerba Pharmaceuticals, a healthcare company creating cannabinoid-based medications primarily for children with neuropsychiatric conditions, set out to uncover why an increasing number of CBD-only patients were reporting minor negative side effects akin to those experienced by THC users. They decided to study what happens to CBD while being digested in the stomach from a CBD tincture, a popular method of CBD consumptions among medical patients. They discovered that, when exposed to gastric acid, CBD degrades to THC, which is then processed and bound within the body.
Exposure to Stomach Acid
CBD can most certainly degrade to THC when exposed to stomach acid, but these conditions were within a lab environment using synthetic gastric acid and were unable to account for the many variables found in a stomach. In the study, just an hour after methanol-emulsified CBD oil was exposed to artificial gastric acid, THC levels spiked dramatically. The solution used was 700 mg of CBD, which degraded to 6.5 mg of THC after 30 minutes, and 13 mg of THC after 1 hour, assuming only 1% of the dosage was soluble.
Building off these reports, another study was conducted in 2017 looking for the same process to occur in live pig stomachs. They introduced a dose of 15 mg/kg of CBD orally twice daily for 5 days, taking blood samples multiple times a day. They looked for both THC and its first metabolite, hydroxy-THC, in the gastrointestinal tract and in the blood samples using liquid chromatography, and were unable to find any traces of THC or its metabolite. With the close connection between pig and human gastrointestinal tract functions, it’s safely assumed that this process cannot occur in humans either with all the of the additional variables at play.
As such, it’s been all-but concluded that the negative THC-like symptoms reported by some CBD patients, the positive drug test results from consumers only taking CBD and other, similar THC issues regarding CBD products come solely from mislabeled and poorly created products, not any chemical reaction in the body itself.
- Merrick, J. Lane, B. Sebree, T. Yaksh, T. O’Neill, C. Banks, SL. Identification of Psychoactive Degradants of Cannabidiol in Simulated Gastric and Physiological Fluid. Cannabis and Cannabinoid Research. (2016)
- Wray, L. Stott, C. Jones, N. Wright, S. Cannabidiol Does Not Convert to Δ9-Tetrahydrocannabinol in an In Vivo Animal Model. Cannabis and Cannabinoid Research. (2017)
- Wall, ME. Perez-Reyes, M. The metabolism of delta 9-tetrahydrocannabinol and related cannabinoids in man. Journal of Clinical Pharmacology. (1981)
- Huestis, MA. Cone, EJ. Henningfield, JE. Blood cannabinoids: I. Absorption of THC and formation of 11-OH-THC and THCCOOH during and after marijuana smoking. Journal of Analytical Toxicology. (1992)
- Mattes, RD. Shaw, LM. Edling-Owens, J. Engelman, K. Elsohly, MA. Bypassing the first-pass effect for the therapeutic use of cannabinoids. Pharmacology, Biochemistry and Behavior. (1993)
- Grotenhermen, F. Pharmacokinetics and pharmacodynamics of cannabinoids. Clinical Pharmacokinetics. (2003)
- Rohrich, J. Schimmel, I. Zorntlein, S. Becker, J. Drobnik, S. Kaufmann, T. Kuntz, V. Urban, R. Concentrations of delta9-tetrahydrocannabinol and 11-nor-9-carboxytetrahydrocannabinol in blood and urine after passive exposure to Cannabis smoke in a coffee shop. Journal of Analytical Toxicology. (2010)
- Hess, C. Kramer, M. Madea, B. Topical application of THC containing products is not able to cause positive cannabinoid finding in blood or urine. Forensic Science International. (2017)
- Miller, S. Introduction to the Endocannabinoid System. Green Flower. (2018)
- Cannabis Edibles. Green Flower. (2018)