Cannabidiol and cognition: a literature review of human randomized controlled trials.
Jyotpal Singh, C. Ellingson, M. A. Shafiq, Jane Alcorn, J. Neary
Behavioural Pharmacology June 10, 2025 DOI: 10.1097/fbp.0000000000000837 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Systematic review Randomized Peer reviewed |
|---|---|
| Population | Healthy participants and patients with neurological disease, psychiatric disease, psychosis, paranoia, schizophrenia, and drug-use disorders, across 36 randomized controlled trials |
| Intervention | Cannabidiol (CBD) |
| Dose | 75-300 mg; 300-400 mg; 600 mg; up to 1000 mg per day; up to 800 mg |
| Topics | CBD |
| Key findings | Across 36 randomized controlled trials, CBD's cognitive effects varied by population and dose: mild improvements in daily activities at 75-300 mg in Parkinson's disease, reduced subjective anxiety at 300-400 mg in psychiatric patients, inconsistent cognitive results at 600 mg in psychosis and paranoia, and minimal cognitive effects at up to 1000 mg/day in schizophrenia and up to 800 mg in substance use disorders. The authors conclude that standardized dosing and formulations are needed to assess efficacy. |
Abstract
Cannabidiol (CBD) is a phytocannabinoid without intoxicating properties. While CBD can improve neurophysiological functions and subjective symptoms, its effect on cognitive function remains unclear. We summarized the available randomized controlled trials investigating CBD administration and cognitive function. A review of the literature was conducted using the following keywords on PubMed/Medline: (cannabis OR cannabidiol OR cannabinoid OR CBD OR Δ9-tetrahydrocannabinol OR tetrahydrocannabinol) AND (neurology OR brain OR psychiatric OR neuroscience OR psychology OR cognition) AND (human) AND (randomized controlled trial OR RCT). The search yielded 1038 articles with 36 total included for this literature review. The articles included healthy participants, neurological disease, psychiatric disease, psychosis, paranoia, schizophrenia, and drug-use disorders. Studies with healthy participants included a variety of dosing strategies, suggesting an effect on cognitive function and sleep quality. In Parkinson's disease, 75-300 mg CBD resulted in mild improvements in daily life activities. Decreases in subjective anxiety were found in patients with psychiatric disease using CBD doses ranging from 300 to 400 mg. In patients with psychosis and paranoia, 600 mg CBD showed inconsistent results in cognitive function. In patients with schizophrenia, up to 1000 mg CBD per day had minimal effects on cognition. Finally, up to 800 mg CBD had minimal effects on cognitive function in patients with substance use disorders. The findings are limited by utilization of acute dosing, variations in CBD dose, and different routes of administration. Standardized dosing and CBD formulations are needed to assess its efficacy for improving cognition.
Comparable studies
Other systematic reviews and meta-analyses on CBD, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Neuroimaging in cannabis use: a systematic review of the literature Cannabis users and controls in neuroimaging studies | 2009 | Systematic review | |
| Cannabis, a cause for anxiety? A critical appraisal of the anxiogenic and anxiolytic properties | 2020 | Systematic review | |
| Effects of Cannabis on Impulsivity: A Systematic Review of Neuroimaging Findings | 2014 | Systematic review | |
| Association between formal thought disorder and cannabis use: a systematic review and meta-analysis Individuals along the psychosis continuum (healthy individuals, patients with... | 2022 | Meta-analysis | n = 5,191 |
| The Relationship Between Cannabis Use and Schizophrenia As a Risk Factor or For Its Therapeutic Potential: A Systematic Review of Evidence | 2025 | Systematic review |
Citations in the library
Cites 13
- Distinct Effects of Δ9-Tetrahydrocannabinol and Cannabidiol on Neural Activation During Emotional Processing Archives of General Psychiatry 2009
- Modulation of effective connectivity during emotional processing by Δ9-tetrahydrocannabinol and cannabidiol The International Journal of Neuropsychopharmacology September 24, 2009
- The acute effects of cannabidiol on the neural correlates of reward anticipation and feedback in healthy volunteers Journal of Psychopharmacology August 5, 2020
- Determining the magnitude and duration of acute Δ9-tetrahydrocannabinol (Δ9-THC)-induced driving and cognitive impairment: A systematic and meta-analytic review. Neuroscience and biobehavioral reviews January 23, 2021
- The “Entourage Effect”: Terpenes Coupled with Cannabinoids for the Treatment of Mood Disorders and Anxiety Disorders Current Neuropharmacology January 23, 2020
and 8 more in the library