Time to case the joint? Teryoshi/plainpicture

COMPONENTS of cannabis might help those addicted to crack cocaine to quit. Such people may find it easier to curb their usage or give up entirely when they take some form of cannabis, suggests a small study that builds on similar results from research in rodents.

“This is a promising development that will provide more alternatives to those in need,” says Ric Curtis at the City University of New York, who wasn’t involved in the work.

Some of the first hints that cannabis might help curb crack cravings were anecdotal, says Curtis, who studied crack dealers in the 1980s. “They would wean themselves off crack by smoking it with marijuana.”


To find out if this approach might work, Michael-John Milloy at the University of British Columbia in Vancouver assessed the findings from three long-term studies of drug users in the city. Across the studies, 3000 people with a history of drug use completed questionnaires detailing their habits, including whether they had started taking cannabis with the intention of reducing their crack cravings.

Milloy and his colleagues identified 122 crack users who started taking cannabis for this purpose. Over an average of 30 months, these individuals were 89 per cent more likely to have reduced their crack use when they were using cannabis, compared with when they were not using it.

“People were 89 per cent more likely to reduce their crack use when they were taking cannabis”

It also appeared to help some of them quit crack altogether or stay off it if they had already done so. “Before intentional cannabis use, 11 per cent were not using crack at all,” says Milloy. “After intentional use, that increased to 28 per cent.” His team presented the results at the Harm Reduction International Conference in Montreal last month.

The study wasn’t a clinical trial, so the team can’t be certain that the decline in crack use wasn’t down to willpower or some other factor. Another flaw in the research is that the team didn’t account for the form or amount of cannabis used.

Still, the results are intriguing and deserve further investigation, says Nora Volkow, director of the US National Institute on Drug Abuse in Maryland.

Milloy is currently planning a randomised and controlled trial, in which half the participants will receive a placebo. The other half will be given measured doses of medical-grade cannabis or specific components of cannabis that don’t deliver a high.

It will be vital to learn which components might help most in treating drug addictions. Cannabis comes in various forms, which might explain why other studies have found that people who take cannabis find it harder to quit cocaine.

Animal studies suggest that a component called cannabidiol (CBD) might be the best bet. This compound is thought to interfere with reward pathways in the brain, potentially limiting the rewarding feeling of taking some addictive drugs, says Volkow. “From doing lots of studies in animals, CBD has been shown to be beneficial in reducing drug intake,” she says.

This article appeared in print under the headline “Cannabis helps addicts quit crack”