CBD Could Help People Quit Cannabis
The results of the very first randomized clinical trial of CBD for cannabis use disorders suggest that prescribed doses of the non-intoxicating constituent of the cannabis plant may help people get rid of this addiction.
In the MRC-funded clinical trial published in The Lancet Psychiatry, researchers administered CBD or a placebo to 82 volunteers who were motivated to stop using cannabis but who had previously failed. They measured the effects of the drug on levels of cannabis use both during a four-week treatment period and up to six months of follow-up.
Since this was the first clinical trial to evaluate CBD for reducing cannabis use, they tested three different doses of CBD in an adaptive design to find out which doses might be the most effective:
- In the first stage of the trial, 48 volunteers were given placebo or CBD in doses of 200 mg, 400 mg or 800 mg. The researchers found that the lower dose of 200 mg of CBD was ineffective, so they dropped it from the trial.
- In the second stage of the trial, the researchers recruited 34 additional volunteers to receive a placebo, 400 mg or 800 mg of CBD. At the end of the trial, they found consistent evidence that 400 mg or 800 mg CBD was more effective than a placebo in reducing cannabis use.
Their results showed that participants treated with CBD had lower levels of cannabis in their urine and more days of abstinence compared to those treated with a placebo.
CBD was well tolerated at all doses and there was no increase in side effects compared to placebo. 94% of the volunteers completed the treatment. Importantly, the tested CBD doses were significantly higher than CBD products bought online or on the street (typically 25 mg per day).
All trial participants encountered a clinical diagnosis of a cannabis use disorder, indicating a problematic pattern of cannabis use that created significant impairment and distress for the individual. All of the participants had failed to quit cannabis at least once before and had participated in the trial as part of an attempt to quit.
Lead author Dr Tom Freeman, Director of the Addiction and Mental Health Group in the Department of Psychology at the University of Bath, explains: “The results of our trial open up a new therapeutic strategy for managing problematic use of cannabis in clinical settings.” As we point out, CBD in daily oral doses of 400 mg and 800 mg has the potential to meet the substantial and currently unmet clinical need for pharmacological treatment of cannabis use disorders.
“While it may seem counterintuitive to treat problematic cannabis use with CBD, a building block of the cannabis plant, THC and CBD have contrasting effects on our own endogenous cannabinoid system. Unlike THC, CBD does not produce an intoxicating or gratifying high, and it shows potential for treating several other medical conditions.”
Cannabis is now the main drug cited by new clients coming to drug treatment services across Europe, with the number of people entering treatment increasing 76% over the past decade. The increase in the treatment of cannabis problems has come along with an increase in the concentrations of THC, the intoxicating component of cannabis. Daily consumption of cannabis with high concentrations of THC is associated with a five times higher risk of psychosis.
Currently, there are no recommended drug therapies to help people with problematic cannabis use. By demonstrating how CBD could be a promising treatment strategy, this trial adds to existing research on the potential medicinal uses of CBD, including the treatment of severe childhood epilepsy syndromes and psychosis. Importantly, the CBD treatment does not include any of the intoxicating constituents of cannabis (THC) which could carry a risk of side effects.
Professor Valerie Curran, senior author and director of the Clinical Psychopharmacology Unit at University College London, UK, said: “Our results indicate that doses of CBD ranging from 400 mg to 800 mg per day have the potential to reduce cannabis use in clinical settings, but higher doses are unlikely to provide additional benefit. Larger studies are needed to determine the extent of the daily benefits of CBD for reducing cannabis use.”