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Updated: May 17, 2026

Administration of Δ9-Tetrahydrocannabinol (THC) in Adolescent and Adult Mice
Published on: August 1, 2025
Synthetic delta-9-tetrahydrocannabinol elicits schizophrenia-like negative symptoms which are distinct from sedation
1Kings College London, The Institute of Psychiatry, De-Crespigny Park, Denmark Hill, London SE5 8AF, UK. paul.morrison@iop.kcl.ac.uk
Objective:
It is unknown if cannabis recreates the negative symptoms of schizophrenia.
Methods:
Healthy male volunteers (n = 22) completed two experimental sessions in which they received intravenous (IV) delta-9-tetrahydrocannabinol (THC) 2.5 mg or placebo in a randomised counterbalanced order. Negative symptoms were rated using the self-reported community assessment of psychic experiences scale (CAPE). Sedation was rated using the mood-adjective check-list (UMACL). Plasma concentrations of THC were measured over the course of the study. Data were analysed by non-parametric tests.
Results:
Participants reported an increase in negative symptoms from baseline under THC but not placebo conditions (p < 0.001). Negative symptoms showed no relationship with self-rated sedation or plasma concentrations of THC.
Conclusions:
At plasma concentrations resembling recreational use, THC elicited schizophrenia-like negative symptoms which were not merely attributable to sedation. In the community, negative symptoms may be an adverse effect of cannabis use.
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