Medical cannabis may help treat cannabis addiction, according to Australian researchers.
In the first study of its kind, cannabis replacement therapy involving cannabis-based medication and cognitive behavioural therapy resulted in 40% fewer cannabis use days by those who smoked the illicit drug, compared with a placebo group.
The 12-week trial, conducted by the University of Sydney and NSW Health, involved 128 cannabis users who had previously tried to curb their use unsuccessfully by taking nabiximol medication.
The cannabis concentrate, comprising equal proportions of cannabidiol and the psychoactive tetrahydrocannabinol, was sprayed under patients’ tongues at an average dose of about 18 sprays a day.
South East Sydney Local Health District Director of Drug & Alcohol Services and University of Sydney Conjoint Professor Nick Lintzeris said the clinical trial provided strong evidence that so-called cannabinoid agonist medication targeting receptors in the brain could reduce the rate of relapse.
“We’ve never had the evidence before that medication can be effective in treating cannabis dependency; this is the first big study to show this is a safe and effective approach,” Professor Lintzeris said.
“The principles are very similar to nicotine replacement; you are providing patients with a medicine which is safer than the drug they’re already using, and linking this with medical and counselling support to help people address their illicit cannabis use.”
Nabiximols have primarily been used to treat pain symptoms associated with multiple sclerosis.
Alternative medical cannabis products exist but are only available through special access schemes and unlike the trial medication, also require Therapeutic Goods Administration approval.
An earlier study by the same researchers had shown nabiximols reduced withdrawal symptoms in a short-term hospital treatment program.
“The latest study is even more important in that it shows that nabiximols can be effective in helping patients achieve longer term changes in their cannabis use,” Professor Lintzeris said.
An oral spray can be an effective substitute for smoked cannabis in heavy recreational users seeking treatment for their cannabis use, according to researchers.
“Our study is an important step in addressing the lack of effective treatments – currently four in five patients relapse to regular use within six months of medical or psychological interventions,” Professor Lintzeris said.
The research was published in JAMA Internal Medicine.
