Hopeful Research into Cannabis Treatment for Cannabis Dependency
Whether you believe you’re addicted to cannabis, or severely dependent on it, if you’re trying to reduce consumption and have been unable to do so with behavioral therapy alone, there may be some hopeful news. Researchers at the University of Sydney have found promising results from their study of a cannabinoid agonist medication that targets brain receptors in reducing cannabis relapse rates.
The study, which was published in the JAMA Internal Medicine noted that cannabis is the most widely-used psychoactive substance worldwide, with some 10% of Australians saying they’ve consumed it in the last year. About 10% of those individuals reported patterns of use that were dependent.
Yet, existing cannabis dependence treatments are ineffective, with relapse rates of about 80% within 6 months to a year of cannabis withdrawal or psychotherapy in the form of cognitive behavioral therapy (CBT). Therefore, there’s a great deal of interest in a cannabinoid agonist medication that may be combined with CBT to help improve treatment outcomes and reduce relapse rates.
To gain more insight into this research, I spoke with the study’s lead author, Conjoint Professor Nicholas Lintzeris, of the University of Sydney’s Faculty of Medicine and Health, and Director of Drug & Alcohol Services at the South East Sydney Local Health District.
Describe what led your team to study using nabiximols in connection with cannabis dependency?
Nicholas Lintzeris: There is a long history of studies looking at different medication approaches for cannabis dependence. Researchers have looked at a wide variety of different types of medications (e.g. antidepressants), although none have shown much promise across studies. In contrast, researchers over the past 10 years have been looking at cannabinoid medications, such as THC-based medications, and these have shown considerable promise. Nabiximols is particularly interesting, as it is a combination of THC and CBD extracted from cannabis plants. CBD dampens some of the side effects of THC (e.g. anxiety, paranoia) and may be considered a safer combination of cannabinoids than high-THC cannabis that predominates in illicit markets in countries such as Australia. Nabiximols also has the advantage of being an oral spray, avoiding the need for patients to smoke cannabis. Finally, nabiximols is licensed in many countries (for multiple sclerosis) and it is always easier to undertake research with a licensed pharmaceutical medication than unlicensed products.
More broadly, the concept of replacement therapy, whereby we prescribe patients a safer form of the drug on which they are dependent, is common in addiction treatment. We use this approach widely in treating nicotine dependence (e.g. nicotine patches) and heroin dependence (e.g. methadone treatment). The rationale is that the medication enables patients to make the behavioral lifestyle changes necessary in stopping an addiction (e.g. routine patterns of behavior, links to certain social networks, etc.), while gradually reducing the medication over time, such that withdrawal and cravings are minimized. This approach is extremely effective in treating other drugs of addiction, and we were optimistic this would also work in treating cannabis dependence.
What did you learn from that first study that helped shape the latest research you did on how using nabiximols can help cannabis users make long-term behavioral changes?