Acceptability, Feasibility, and Effectiveness of Concurrent High-Definition Transcranial Direct Current Stimulation and Cue Exposure in Cannabis Use Disorder: A Pilot Double-Blind Randomized Controlled Trial.

Objectives: We studied the acceptability, feasibility, tolerability, and preliminary effectiveness of combined cue exposure and anodal high-definition transcranial direct current stimulation (HD-tDCS) on the right dorsolateral prefrontal cortex (DLPFC) on cannabis craving in cannabis use disorder (CUD).

Methods: We randomly assigned 48 participants equally in 4 groups: A, tDCS and cannabis cue exposure; B, tDCS and neutral image; C, sham tDCS and cue exposure; and D, sham tDCS and neutral image. The images were validated by Delphi consensus. All participants received 6 sessions. We explored the acceptance, protocol completion, and follow-up rates. We assessed cannabis cravings twice, at the end of sessions and 4 weeks after intervention; change in frequency and amount of cannabis and other substance use were assessed at 4 weeks after intervention; working memory and executive functions were tested at the end of sessions. We performed an intention-to-treat analysis.

Results: We observed low acceptance (19.6%) but high completion (91.7%) and follow-up rates. There were motivational and logistical reasons for low acceptance; monetary compensation improved treatment acceptance. Participants in all groups showed significant reductions in cannabis cravings at the end of sessions, except for group C, the reduction in cravings sustained at the follow-up. Frequency and amount of cannabis use reduced, and cognitive outcomes improved in all 4 groups; however, there was no between-group difference, and changes were higher in groups B and D. Adverse effects and attrition were not different between HD-tDCS and sham treatment.

Conclusions: Anodal right DLPFC HD-tDCS is a safe and promising treatment for CUD. Cue exposure does not add to its effect.