A narrative review of psychological cannabis use treatments with and without pharmaceutical adjunct

Background: As policy responses to cannabis use and availability change internationally, levels of cannabis use disorder rise and treatment seeking increases. Diversion to cannabis treatment from the criminal justice system also increases demand in the system. At a time of developing treatment systems in response to this demand, an understanding of the evidence is increasingly important. Objective: To provide a narrative review of the developing evidence-base for psycho-social interventions for cannabis use disorder, including adjunctive cannabinoid agonist therapy. Method: Two researchers independently conducted a literature search for articles published prior to February 2016, located through online search of four electronic databases (Google Scholar, CINAHL, Medline, and PsycINFO). Only randomised controlled trials describing treatment(s) for cannabis use or cannabis use disorder with a measure of either cannabis use frequency or cannabis use disorder severity were included. Non-English papers, review papers, posters, opinion pieces, letters or editorials, case studies (N<10) and published abstracts were excluded. Results: The cannabis treatment most likely to be effective for adolescents and adults is based on the combination of Motivational Enhancement Therapy (MET) and Cognitive Behavioural Therapy (CBT) with the inclusion of contingency management and agonist replacement therapy showing promise. Conclusion: A more concrete and robust evidence base is required for these interventions. Replication of treatment studies is needed using standardised interventions, methods and measures to minimise conflicting findings, inconsistent follow-up periods and relatively poor treatment effects over time.(243 words).