CBD May Actually Increase THC’s Intoxicating Effect, New Marijuana Study Finds, Contrary To Conventional Wisdom

A recent study examining the combined effects of THC and CBD suggests that, contrary to widespread belief, CBD may actually heighten the experience of a marijuana high rather than diminishing it.

The research, published in the journal Clinical Pharmacology and Therapeutics, found that people who took a high dose of CBD (450 mg) alongside a smaller, 9-mg dose of THC “did not reduce, but instead significantly increased subjective, psychomotor, cognitive, and autonomous effects of THC.”

Smaller doses of CBD, such as 10 mg and 30 mg, did not appear to have the same effect.

The findings are noteworthy in part because conventional wisdom among many in the cannabis community is that CBD can help lessen a too-intense marijuana high by blocking THC’s interaction with the brain’s CB1 receptors. The study suggests that at some level, CBD in fact begins to make the felt effects of cannabis more intense.

“In contrast to what is commonly hypothesized in (popular) literature, CBD did not reduce the adverse effects of THC.”

A seven-person research team in the Netherlands and the U.S. authored the new report, which looked at the results of a randomized, double-blind, placebo-controlled trial involving 37 healthy volunteers.

The team was attempting to test the hypothesis that CBD would reduce the adverse effects of THC. If confirmed, they believed the effect could help make therapeutic THC more tolerable for chronic pain patients by reducing the substance’s psychoactive effects.

Evidence, however, showed the opposite effect. Moreover, the addition of CBD did not appear to produce any additional pain-relieving effects.

“This study found no evidence of CBD reducing adverse THC effects. On the contrary, THC effects were significantly increased by 450 mg of CBD.”

“These results provide evidence against the hypothesis that CBD attenuates THC effects, highlight the potential for drug interactions even at low doses of CBD, and add to the understanding of THC analgesia,” authors wrote in the report.

One author, Geert van Groeneveld, a professor at Leiden University Medical Center and the CEO of the Centre for Human Drug Research, was emphatic that the team’s findings refute the idea that CBD might lessen anxiety or otherwise ease the adverse effects of THC.

“CBD does not in any way alleviate psychomimetic effects of THC or reduce anxiety,” Groeneveld told PsyPost. “If anything, in higher dose levels it will enhance the effects of THC because the breakdown of THC in the liver is inhibited by CBD.”

The study’s conclusion adds to past findings that combinations of cannabinoids and other chemicals in cannabis may produce a stronger high than THC on its own.

Separate research published last year, for example, found that cannabis products with a more diverse array of natural cannabinoids produced a stronger psychoactive experience that lasts longer than the high generated by pure THC alone.

Another scientific review, published this past spring, found that the “complex interaction between phytocannabinoids and biological systems offers hope for novel treatment approaches,” laying the groundwork for a new era of innovation in cannabis-based medicines.

That report, published in the International Journal of Molecular Sciences, underscored the potential of whole-plant cannabis medicine—incorporating the variety of cannabinoids, terpenes and other compounds produced by the cannabis plant—rather than simply THC or CBD on their own.

While results of the new study suggest CBD may not do much to reduce the side-effects of THC consumption, another study published earlier this year found that a terpene produced by marijuana, D-limonene, reduced anxiety and paranoia in people who took THC.

Although the terpene modulated the anxiety-like effects, however, it seemed to have minimal effect otherwise on participants’ experiences.

The addition of D-limonene, which is found in many citrus fruits in addition to cannabis and smells like oranges, “had little impact on other common acute subjective, cognitive, or physiological effects of THC,” researchers found. Inhaling the vaporized terpene by itself, meanwhile, “did not produce any acute effects that differ from placebo.”

Researchers Identify ‘Previously Undiscovered Cannabis Compounds’ That Give Marijuana Strains Their Unique Aromas

Photo courtesy of Kimzy Nanney.