Study From King's College London Shows CBD Can't Reduce Negative Effects Of Cannabis, But It Can Make You Cough More

Can CBD minimize some of the negative effects of marijuana?

According to new research from the Institute of Psychiatry, Psychology & Neuroscience (IoPPN) at King's College London, no, it can’t.

The study, published in Neuropsychopharmacology examined whether marijuana with higher levels of CBD can protect consumers from psychotic experiences and memory problems, reported Medical Express.

Research Summary

Forty-six healthy volunteers participated and completed a randomized and double-blind trial. There were four experiments, and in each, every participant inhaled marijuana vapor with 10mg of THC and a different level of CBD (0mg, 10mg, 20mg, or 30mg).

After that, they had to perform several tasks, fill out questionnaires and complete interviews created to assess the effect on their cognitive abilities, the severity of psychotic symptoms, and how pleasurable the marijuana experience was.

Previously the same study confirmed that pre-emptively taking a high dose of CBD in a capsule several hours before weed could reduce the adverse effects of THC.

The new research revealed that the higher dose of CBD didn’t notably change the effect of THC on cognitive performance, psychotic symptoms, or how enjoyable the experience was.

"None of the CBD levels studied protected our volunteers from the acute negative effects of cannabis, such as anxiety, psychotic symptoms, and worse cognitive performance,” Dr. Amir Englund, a research fellow at King's IoPPN and the study's lead author said. “It also did not change the quality of the intoxication in any way.

"The only effect of CBD we saw was that as the concentration of CBD increased, the more the participants coughed, Englund continued. “We asked volunteers to listen to a favorite song on each visit and taste a piece of chocolate. Although cannabis increased the pleasurability of music and chocolate compared to when volunteers were sober, CBD had no impact.”

Conclusions

He further highlighted that it may still be safer for consumers to pick marijuana with higher CBD:THC ratios, only because the same amount of marijuana will contain less THC than a lower CBD:TCH variety.

“Overall, our advice to people wanting to avoid the negative effects of THC is to use less of it,” Englund concluded.

Professor Philip McGuire, the study's senior author and former Head of the Department of Psychosis Studies at King's IoPPN explained the importance of these kinds of studies. "These findings make an important contribution to the ongoing debate around the risks of cannabis use,” McGuire said. “While CBD on its own is known to have a number of positive effects in humans, our data suggest that, at the doses that are typically present in cannabis, it does not protect against the negative effects of THC. This challenges the commonly held view by many cannabis users that cannabis with a higher CBD content provides a buffer against the adverse effects of cannabis."

Previous Studies

Interestingly though, a study published in May in The Journal of Psychopharmacology had some opposing findings.

Researchers used data from another study that examined the brain activity of 17 healthy participants taking various marijuana strains (some high in both THC and CBD, others high in THC but without CBD, and placebo), using functional magnetic resonance imaging (fMRI).

In this new research, the study author Mat Wall, a senior imaging scientist at Invicro and his colleagues measured brain activity in 23 healthy participants after they consumed oral CBD and a placebo. They also used fMRI to examine brain activity.

The researchers revealed that THC and CBD have opposing effects.

The findings suggested that “different types of cannabis have different effects on the brain,” Wall said. “High-strength, relatively pure-THC cannabis can severely affect some brain networks, but when THC is combined with cannabidiol (CBD) in a more ‘balanced’ way, these effects may be reduced somewhat, making a balanced strain of cannabis potentially safer to use. CBD by itself seems to have quite minimal effects on the brain networks we looked at, which means it’s probably safe for use as a potential therapy.”

Though the study concluded that CBD can minimize some of the negative effects THC has on the brain, there were important limitations to the research – both studies were very small, and data were used from two different cohorts of subjects which means direct comparison between those two groups was not really possible. 

Photo: Benzinga Edit; Sources: Erin_Hinterland, mohamed_hassan and surfwiz17 by Pixabay