FEB 01, 2019 5:02 PM PST

Study Adds to Our Knowledge of CBDs

WRITTEN BY: Amy Loriaux

Cannabidiol (CBD) oil has been touted as the "safe" cannabinoid, different from its psychoactive cousin delta9-tetrahydrocannabinol (THC). Reports have suggested that CBDs have therapeutic benefits, are generally considered non-psychoactive, and, most prominently, CBDs counteract the effects of THC, essentially bringing down your "high". Well, a new study out of Australia by Dr. Nadia Solowi and colleagues have found evidence that CBD actually enhances the effects of THC in ingested cannabis.

Photo source: Pixabay.com

The authors, who published in the journal European Archives of Psychiatry and Clinical Neuroscience, used subjective reports from 36 study participants while on THC alone or a combination of THC and low or high doses of CBD. It was previously believed that these two substances counteracted each other, at both the subjective level and the pharmacological level.

THC is a partial agonist at CB1 receptors. This means it weakly activates the CB1 receptor while blocking endogenous ligands (such as endocannabinoids), while CBD is a low-affinity CB1 and CB2 receptor agonist. That means that it activates endogenous cannabinoid receptors, but are easily unbound. It is also a negative allosteric modulator at CB1, which means it reduces ligands from binding to CB1. Thus, pharmacologically speaking, it would seem that CBD would counteract THC's effect at the receptor level.

The previous evidence that CBD counteracts THC comes from in vitroex vivo, and human imaging studies. A functional resonance imaging (fMRI) study showed that different regions of the brain were activated/inactivated when participants were pretreated with CBD before THC administration (both IV). However, this study does not definitively demonstrate a CBD-countereffect of THC, nor suggests a mechanism.

Photo source: Adobe (with permission)

The counteractive assumption may also be due to the different effects THC and CBD produce when taken alone. Too high of a dose of THC can produce psychotic-like symptoms, while CBD has anti-psychotic properties. Also of note, is the rise in psychotic episodes in marijuana smokers of today's cannabis, which has had CBD bred out to leave as little as 3% to 0% of CBD left. These high-potent strains also have a significant amount of THC in them (as much as 20%). These observations contribute to the idea that CBD and THC oppose each other.

While CBD does ameliorate the anxiety- and psychosis-producing properties, there are also additive effects. For one, the preclinical literature has shown additive effects of CBD on THC's effects on movement in rats. Furthermore, CBD administration potentiates THC's antinociceptive (pain-blocking). And not only THC's "good" effects were potentiated, but also were its "bad" ones. CBD exacerbated the impairing effects of THC on spatial memory, hypoactivity, and hypothermia.

The current study found that the interaction of CBD and THC is very complex and nuanced and that the dosages of each, when combined, have a lot of influence on the subjective feelings of being "high".  Interestingly, a high-dose of CBD alone produced feelings of a "high". However, the end results found that the participants felt the "highest" with a combination of THC and a low dose of CBD. They felt the least "high" with THC administered with a high dose of CBD. Thus, to say that one compound counteracts the other is an oversimplification. Many factors, including dose, potency and route of administration have to be considered when deciding how and when to take extra CBDs while smoking (legally, please) pot. 

Sources: NeuropsychopharmacologyEuropean Archives of Psychiatry and Clinical Neuroscience, British Journal of PharmacologyGlaskoSmithKline, JAMA PsychiatryNeuroscience and Biobehavioral ReviewsPsychopharmacologia, Psychopharmacology 

About the Author
  • I currently work at a small CRO involved in clinical trial management.
You May Also Like
NOV 22, 2019
Health & Medicine
NOV 22, 2019
Federal Government Weighs in on Marijuana and Opioid Addiction
The U.S. government is weighing in on the hot topic of whether or not medical marijuana is a successful tool in treating opioid addiction by barring the us...
DEC 02, 2019
Cannabis Sciences
DEC 02, 2019
Scientists List Several Reasons Not to Use Marijuana During Pregnancy
An estimated 16 percent of women use marijuana on a daily basis while pregnant, and a large majority of women do so without realizing the potential health...
DEC 17, 2019
Cannabis Sciences
DEC 17, 2019
Let's Talk Cannabis: Vermont Launches New Site
When cannabis is legalized, people have questions. The state of Vermont created a new website to advise people on safe medical and recreational cannabis us...
JAN 07, 2020
Cannabis Sciences
JAN 07, 2020
Health Concerns with Cannabis Edibles
After the legalization of edible cannabis products in Canada in October of last year, members of the Canadian Medical Association speak up about the risks ...
FEB 12, 2020
Cannabis Sciences
FEB 12, 2020
Smoking Marijuana Leads to False Memory Formation
Smoking marijuana is known to make people forgetful. Now however, research has shown that smoking the substance may also make people remember things that n...
FEB 25, 2020
Cannabis Sciences
FEB 25, 2020
Marijuana Use Among Seniors Over 65 Skyrockets
Following its legalization, cannabis and its products have become increasingly popular- and not just among young people. Researchers from New York Universi...
Loading Comments...