Acute effects of cannabis on speech illusions and psychotic-like symptoms: two studies testing the moderating effects of cannabidiol and adolescence. Issue 12 (28th September 2021)

• Record Type: Journal Article
• Authors: Mokrysz, Claire; Shaban, Natacha D. C.; Freeman, Tom P.; Lawn, Will; Pope, Rebecca A.; Hindocha, Chandni; Freeman, Abigail; Wall, Matthew B.; Bloomfield, Michael A. P.; Morgan, Celia J. A.; Nutt, David J.; Curran, H. Valerie
• Is Part Of: Psychological medicine. Volume 51:Issue 12(2021)
• Page Start: 2134
• Page End: 2142
• Publication Date: 2021-09-28
• Subjects: acute effects -- adolescence -- cannabidiol -- cannabis -- CBD -- psychosis -- psychotic-like -- speech illusion -- vulnerability; Psychiatry -- Periodicals; Medicine and psychology -- Periodicals; Clinical psychology -- Periodicals; 616.89
• DOI: 10.1017/S0033291720001038
• Languages: English
• ISSNs: 0033-2917

Abstract

Abstract: Background: Acute cannabis administration can produce transient psychotic-like effects in healthy individuals. However, the mechanisms through which this occurs and which factors predict vulnerability remain unclear. We investigate whether cannabis inhalation leads to psychotic-like symptoms and speech illusion; and whether cannabidiol (CBD) blunts such effects (study 1) and adolescence heightens such effects (study 2). Methods: Two double-blind placebo-controlled studies, assessing speech illusion in a white noise task, and psychotic-like symptoms on the Psychotomimetic States Inventory (PSI). Study 1 compared effects of Cann-CBD (cannabis containing Δ-9-tetrahydrocannabinol (THC) and negligible levels of CBD) with Cann+CBD (cannabis containing THC and CBD) in 17 adults. Study 2 compared effects of Cann-CBD in 20 adolescents and 20 adults. All participants were healthy individuals who currently used cannabis. Results: In study 1, relative to placebo, both Cann-CBD and Cann+CBD increased PSI scores but not speech illusion. No differences between Cann-CBD and Cann+CBD emerged. In study 2, relative to placebo, Cann-CBD increased PSI scores and incidence of speech illusion, with the odds of experiencing speech illusion 3.1 (95% CIs 1.3–7.2) times higher after Cann-CBD. No age group differences were found for speech illusion, but adults showed heightened effects on the PSI. Conclusions: Inhalation of cannabis reliably increases psychotic-like symptoms in healthy cannabis users and may increase the incidence of speech illusion. CBD did not influence psychotic-like effects of cannabis. Adolescents may be less vulnerable to acute psychotic-like effects of cannabis than adults.