5. Acute effects of four CBD:THC ratios on attentional bias to cannabis and food cues: a randomized, double-blind, crossover study

Introduction and aims: Increasing THC content in cannabis has been associated with higher incidence of cannabis use disorder, whereas CBD has shown to help in reducing cannabis use in individuals with cannabis use disorder. This study aimed to determine if THC acutely increases implicit wanting and explicit liking of cannabis stimuli and food stimuli in healthy people, and if CBD reduces this effect, through manipulating the ratio of CBD:THC. Method/ approach: Forty-six healthy volunteers were recruited to a randomised, double-blind, within-subject study. Each was assessed on four occasions, following inhalation of cannabis containing CBD and THC in one of four different ratios: (0mg CBD: 10mg THC; 10mg CBD: 10mg THC; 20mg CBD: 10mg THC; 30mg CBD: 10mg THC). Participants completed two tasks: 1) attentional bias (AB), including 28 target (drug/food) and non-target (control) stimuli measuring implicit wanting; 2) picture rating (PR) where drug, food and control stimuli were rated on a 7-point scale, measuring explicit liking. Key findings: No significant differences were seen in AB or PR scores between baseline and the 0:1 condition (p>0.05). Similarly, there were no significant effect of CBD on either AB or PR scores (p>0.05). Discussions AND conclusions There was no change seen in implicit wanting or explicit liking with acute THC or CBD in healthy participants with infrequent cannabis use. The effect of THC is more likely to be seen in individuals with cannabis use disorder. Due to the promise of CBD as a treatment for addiction, further research needs to be performed in this population to establish potential mechanisms of action.