Separate and combined effects of alcohol and cannabis on mood, subjective experience, cognition and psychomotor performance

Co-use of alcohol and cannabis is associated with increased frequency and intensity of use and related problems. Researchers examined acute effects of alcohol and cannabis on mood, subjec-tive experience, cognition, and psychomotor performance.
Twenty-eight healthy cannabis users aged 19-29 years with recent history of binge drinking were included in the trial. Participants received: placebo alcohol and placebo cannabis (<0.1% THC); alcohol (target breath alcohol content [BrAC] 80 mg/dL) and placebo cannabis; placebo alcohol and active cannabis (12.5% THC); and active alcohol and cannabis over four sessions. Profile of Mood States (POMS), Addiction Research Centre Inventory (ARCI), verbal free recall (VFR), Digit Symbol Substitution Test (DSST), Continuous Performance Test (CPT), and grooved pegboard (GPB) task were administered before and after each session.
Significant effects of condition were found for the POMS (Tension-Anxiety, Confusion) and ARCI (MBG, LSD, PCAG, Euphoria, Sedation), predominantly with greater increases emerging after cannabis or alcohol-cannabis combined relative to placebo. Significant effects were found for VFR (immediate total and delayed recall, percent retained), DSST (trials attempted, trials correct, reaction time), and GPB (non-dominant hand) predominantly with greater declines in performance after alcohol and alcohol-cannabis combined relative to placebo and/or cannabis.
Cannabis appeared to affect mood and subjective experience, with minimal impact on cognitive performance. Alcohol appeared to impair cognitive and psychomotor performance, with minimal impact on mood and subjective experience. Acute effects of alcohol and cannabis combined were additive at most, the researchers conclude.
Source: Christine M. Wickens, Madison Wright, Robert E. Mann, Bruna Brands, Patricia Di Ciano, et al., Separate and combined effects of alcohol and cannabis on mood, subjective experience, cognition and psychomotor per-formance: A randomized trial, Progress in Neuro-Psychopharmacology and Biological Psychiatry, Volume 118, 2022, 110570, ISSN 0278-5846.