Pharmacotherapy for the treatment of cannabis use disorder: A systematic review

Background: Cannabis use disorder (CUD) is a growing concern, and evidence-based data are needed to inform treatment options. Purpose: To review the benefits and risks of pharmacotherapies for the treatment of CUD. Data Sources: MEDLINE, PsycINFO, Cochrane Database of Systematic Reviews, and clinical trial registries from inception through September 2019. Study Selection: Pharmacotherapy trials of adults or adolescents with CUD that targeted cannabis abstinence or reduction, treatment retention, withdrawal symptoms, and other outcomes. Data Extraction: Data were abstracted by 1 investigator and confirmed by a second. Study quality was dually assessed, and strength of evidence (SOE) was determined by consensus according to standard criteria. Data Synthesis: Across 26 trials, the evidence was largely insufficient. Low-strength evidence was found that selective serotonin reuptake inhibitors (SSRIs) do not reduce cannabis use or improve treatment retention. Low- to moderate-strength evidence was found that buspirone does not improve outcomes and that cannabinoids do not increase abstinence rates (moderate SOE), reduce cannabis use (low SOE), or increase treatment retention (low SOE). Across all drug studies, no consistent evidence of increased harm was found. Limitations: Few methodologically rigorous trials have been done. Existing trials are hampered by small sample sizes, high attrition rates, and heterogeneity of concurrent interventions and outcomes assessment. Conclusion: Although data on pharmacologic interventions for CUD are scarce, evidence exists that several drug classes, including cannabinoids and SSRIs, are ineffective. Because of increasing access to and use of cannabis in the general population, along with a high prevalence of CUD among current cannabis users, an urgent need exists for more research to identify effective pharmacologic treatments.