Project details:
In May 2025, Bristol ESG were asked to undertake a systematic review of the evidence for the comparative effectiveness, safety and acceptability of pharmacological and psychosocial interventions for the treatment of cannabis use disorders (CUD). The project is funded by the NIHR Evidence Synthesis Programme (project number: NIHR176717) and involves a secondary network meta-analysis of data from two completed systematic reviews examining the effectiveness and safety of pharmacotherapies (NIHR165373) and psychosocial interventions (NIHR167862) for CUD in adults and young persons aged ≥16 years.
Project status: completed
Contact: bristol-esg@bristol.ac.uk
What is the problem?
Cannabis is commonly used worldwide as a recreational drug. Cannabis use disorder is a condition characterized by frequent use, craving and inability to stop using cannabis even when it is causing physical or psychological problems for the user. This condition has become much more common during the past three decades and this has led to an increase in the number of people seeking treatment for it. While specific medicines are not widely available and none are approved for this purpose, psychosocial treatments (such as talking therapies, or giving people incentives like vouchers for staying in treatment) are currently the first choice of treatment.
What did we do?
We brought together the available evidence on medicines and psychosocial treatments for cannabis use disorder. We compared the different types of treatments (or combination of treatments) to identify which are the best approaches for the people with cannabis use disorder.
What did we find?
We combined the results from 57 studies involving over 6,000 people with cannabis use disorder. There was very little reliable evidence that medicines help reduce cannabis use. Medicines such as CBD (non-intoxicating part of cannabis), NAC (supplement helping to balance brain chemicals linked to cravings and self-control), and varenicline (medicine used to help people quit smoking), might help people stop using cannabis or stay in treatment, but the evidence is weak. Many medicines had no clear benefit and some of them had side effects. However, some psychosocial interventions may help people reduce cannabis use, achieve abstinence and stay in treatment. Useful therapies involved teaching people skills to manage difficult emotions, accept challenging thoughts and stay focused on the present moment, or practical strategies to change unhelpful thoughts and actions and boost motivation, as well as giving people incentives for staying off cannabis or staying in treatment. Overall, the evidence is limited and uncertain, meaning we cannot be confident about which treatments work best. More high-quality studies are needed to understand which treatments are safe and effective. For now, talking therapies and incentives remain the main option for people seeking help with cannabis use disorder.
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