Abstract
BACKGROUND Sub-anesthetic ketamine infusions may benefit a range of psychiatric conditions, including alcohol and cocaine use disorders. Currently, there are no effective pharmacological treatments for cannabis use disorder. OBJECTIVES The objective of this uncontrolled proof of concept trial was to test the feasibility, tolerability, and potential therapeutic effects of integrating ketamine infusions with a behavioral platform of motivational enhancement therapy and mindfulness-based relapse prevention in treating cannabis use disorder (CUD). METHODS Eight cannabis-dependent individuals (four female, four male) receiving motivational enhancement therapy and mindfulness-based relapse prevention behavioral treatments completed this single-blind outpatient 6-week study. Participants received either one or two infusions of ketamine (0.71 mg/kg [infusion 1]; 1.41 mg/kg [infusion 2] for non-responders) during the study. Participants self-reported cannabis use (Timeline Follow-Back) and underwent an assessment of confidence in abstaining from using cannabis (Drug-Taking Confidence Questionnaire) at predetermined time points throughout the study. RESULTS Ketamine infusions were well-tolerated and there were no adverse events. Frequency of cannabis use decreased significantly from baseline (B = 5.1, s.e = 0.7) to the week following the first infusion (B = 0.8, s.e = 0.412), and remained reduced at the end of the study (B = 0.5, s.e = 0.3). Participants' confidence in their ability to abstain from cannabis in potentially triggering situations increased significantly from baseline to the end of study. CONCLUSIONS These findings suggest that combining ketamine with behavioral therapy is feasible,tolerable, and potentially helpful, in treating cannabis-dependent individuals.
