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25 results for "Meta-analysis: What does the research say about CBD?"

Cannabis and Mental Health: A Systematic Review and Meta-analysis of the Neuropsychiatric Effects, Therapeutic Potentials, and Policy Implications of THC and CBD

Archives of Psychiatry and Mental Health July 29, 2026 Diamond Onyekachi Okoroezi

Aim: This systematic review and meta-analysis examined the neuropsychiatric effects of cannabis, focusing on the contrasting roles of Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD). It evaluated their associations with psychiatric outcomes, assessed the therapeutic potential of cannabis-based products (CBPs), and identified evidence gaps relevant to clinical practice and mental health...

Acute behavioural effects of low-dose cannabidiol: A randomised crossover trial in healthy volunteers.

Journal of Psychopharmacology July 15, 2026 Lucy A Chester, François-Olivier Hebert, Pamela Lachance-Touchette et al.

BACKGROUND Cannabidiol (CBD) is widely consumed in low-dose products. However, evidence for its psychotropic effects at non-clinical doses is sparse and inconsistent. AIMS To characterise the acute behavioural effects of low-dose synthetic CBD in healthy volunteers. We hypothesised that 200 mg of CBD would produce a greater peak pleasant drug effect than a placebo. METHODS In a triple-blind,...

Prophylactic efficacy of cannabidiol and sodium nitroprusside in a ketamine model of schizophrenia: sex-dependent effects on positive-like and cognitive impairments

Brazilian Journal of Psychiatry June 16, 2026 Daniel B.a. Prado, Matheus T. Rossignoli, Rafael N. Ruggiero et al.

Objective: Current treatments for schizophrenia (SZ) are often not effective for all symptoms, with sex-dependent effects poorly understood. Cannabidiol (CBD) and sodium nitroprusside (SNP) have emerged as potential prophylactic options. We evaluated their efficacy in preventing positive, negative, and cognitive deficits in a ketamine (KET) rodent model of SZ in both sexes. Methods: Wistar rats...

Psychedelic-Assisted Psychotherapy for the Treatment of PTSD: A Systematic Review and Meta-Analysis

Psychoactives June 8, 2026 Fizza Mitter, Anton Sheptooha, Janni Leung et al.

Post-traumatic stress disorder (PTSD) remains inadequately treated by existing pharmacological and psychological interventions, prompting growing interest in psychedelic-assisted psychotherapy. Although randomised controlled trials have evaluated several psychedelic agents for PTSD, to our knowledge, no prior PTSD-specific synthesis has quantitatively examined multiple agent classes within a...

Effects of THC, CBD, and Their Combination on EEG Dynamics in Rats.

Physiological research May 12, 2026 Marcel Bochin, Čestmír Vejmola, Vlastimil Koudelka et al.

Cannabinoids modulate brain network activity, yet the spatial organization and temporal evolution of their electrophysiological effects remain insufficiently characterized in animal models. Here, we investigated how acute oral administration of ?9-tetrahydrocannabinol (THC; 10 mg/kg), cannabidiol (CBD; 10 mg/kg), and their combination influences resting-state EEG dynamics in freely moving rats....

Effect of cannabinol, tetrahydrocannabivarin and cannabidiol on voluntary alcohol consumption.

Alcohol and alcoholism (Oxford, Oxfordshire) March 17, 2026 Ieva Poceviciute, Martynas Arbaciauskas, Rokas Buisas et al.

Previous studies have demonstrated that the endocannabinoid system plays a significant role in the development of alcohol use disorder (AUD), and CB1 receptor antagonists/inverse agonists show promise as a novel AUD pharmacotherapy. However, these compounds failed in clinical trials due to the severe psychiatric side effects. Non-psychoactive phytocannabinoids may have a better safety profile...

Cannabidiol Mitigates Ketamine-Induced Hyperlocomotion Via Allosteric Potentiation of Ventral Tegmental Glycine Receptor α1 Signaling.

Biological Psychiatry March 16, 2026 Xianglian Wang, Jing Xia, Heyi Luo et al.

Ketamine produces rapid antidepressant and antidepressant-like effects in both humans and animal models. However, its therapeutic benefits are tempered by psychoactive side effects, such as hyperlocomotion associated with enhanced dopaminergic activity in the ventral tegmental area (VTA). We tested the therapeutic effect of cannabidiol (CBD) on locomotor activity after systemic (30 mg/kg) or...

Acute cannabidiol (CBD), tetrahydrocannabinol (THC) and their mixture (THC:CBD) exert differential effects on brain activity and blood flow in rats: A translational neuroimaging study.

Journal of psychopharmacology (Oxford, England) March 1, 2026 Eilidh Macnicol, Michelle Kokkinou, Maria Elisa Serrano Navacerrada et al. 2 citations

Cannabis constituents, including Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), show distinct pharmacological profiles with therapeutic relevance for neurological and psychiatric conditions. THC exerts euphoric effects primarily via CB1 receptor activation, while CBD displays non-euphoric properties affecting various pathways. This study evaluated the effects of THC, CBD, and their...

Is Cannabidiol (CBD) a Non-Psychoactive Phytocannabinoid?

Psychoactives February 3, 2026 Eliana Rodrigues

Interest in psychoactive substances, including psychedelics, is rapidly expanding in medical, academic, and other popular fields. Despite the classifications established within the psychopharmacological scientific community, certain plants, animals, and fungi, as well as the substances obtained from them, have been misclassified by both the media and academic circles. This opinion piece aims to...

A Systematic Review of Therapeutic Potential of Illicit Drugs: A Narrative Overview of How Cannabinoids and Psychedelics Can be Used in Medicine

Iranian Journal of Chemistry & Chemical Engineering December 7, 2025 Sajedeh Rabipour, Evan Abdolkareem Mahmood, Abdol Ghaffar Ebadi et al.

To aid the therapeutic process, illicit chemical substances and drugs are used in drug therapy. Various cultures have used illegal substances for thousands of years in medicine and various practices. The present study is a general approach to pharmaceutical science and attempts to contextualize drug-assisted therapy through an integrative literature review. All related articles were found...

Cannabis, a cause for anxiety? A critical appraisal of the anxiogenic and anxiolytic properties

Journal of Translational Medicine October 2, 2020 Lara Sharpe, Justin Sinclair, Andrew Kramer et al. 122 citations

BACKGROUND: -tetrahydrocannabinol (THC) has been associated with an anxiogenic response, while anxiolytic activity has been attributed mainly to cannabidiol (CBD). In animal studies, the effects of THC are highly dose-dependent, and biphasic effects of cannabinoids on anxiety-related responses have been extensively documented. A more precise assessment is required of both the anxiolytic and...

Cannabidiol (CBD) content in vaporized cannabis does not prevent tetrahydrocannabinol (THC)-induced impairment of driving and cognition

Psychopharmacology May 1, 2019 Thomas R. Arkell, Nicholas Lintzeris, Richard C. Kevin et al. 177 citations

BACKGROUND: The main psychoactive component of cannabis, delta-9-tetrahydrocannabinol (THC), can impair driving performance. Cannabidiol (CBD), a non-intoxicating cannabis component, is thought to mitigate certain adverse effects of THC. It is possible then that cannabis containing equivalent CBD and THC will differentially affect driving and cognition relative to THC-dominant cannabis. AIMS:...

The neuropsychopharmacology of cannabis: A review of human imaging studies

Pharmacology & Therapeutics October 20, 2018 Michael Bloomfield, Chandni Hindocha, Sebastian F Green et al. 236 citations

receptor. Acutely, cannabis and THC produce a range of effects on several neurocognitive and pharmacological systems. These include effects on executive, emotional, reward and memory processing via direct interactions with the endocannabinoid system and indirect effects on the glutamatergic, GABAergic and dopaminergic systems. Cannabidiol, a non-intoxicating cannabinoid found in some forms of...

Inverted U-Shaped Dose-Response Curve of the Anxiolytic Effect of Cannabidiol during Public Speaking in Real Life

Frontiers in Pharmacology May 11, 2017 Antônio Waldo Zuardi, Natália Pegoraro Rodrigues, Angélica L. Silva et al. 292 citations

The purpose of this study was to investigate whether the anxiolytic effect of cannabidiol (CBD) in humans follows the same pattern of an inverted U-shaped dose-effect curve observed in many animal studies. Sixty healthy subjects of both sexes aged between 18 and 35 years were randomly assigned to five groups that received placebo, clonazepam (1 mg), and CBD (100, 300, and 900 mg). The subjects...

Acute and chronic effects of cannabinoids on effort-related decision-making and reward learning: an evaluation of the cannabis ‘amotivational’ hypotheses

Psychopharmacology September 2, 2016 Will Lawn, Tom P. Freeman, Rebecca Pope et al. 177 citations

RATIONALE: Anecdotally, both acute and chronic cannabis use have been associated with apathy, amotivation, and other reward processing deficits. To date, empirical support for these effects is limited, and no previous studies have assessed both acute effects of Δ-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), as well as associations with cannabis dependence. OBJECTIVES: The objectives of...

Cannabidiol inhibits THC-elicited paranoid symptoms and hippocampal-dependent memory impairment

Journal of Psychopharmacology October 5, 2012 Amir Englund, Paul D. Morrison, Judith Nottage et al. 463 citations

Community-based studies suggest that cannabis products that are high in Δ⁹-tetrahydrocannabinol (THC) but low in cannabidiol (CBD) are particularly hazardous for mental health. Laboratory-based studies are ideal for clarifying this issue because THC and CBD can be administered in pure form, under controlled conditions. In a between-subjects design, we tested the hypothesis that pre-treatment...

Acute Effects of a Single, Oral dose of d9-tetrahydrocannabinol (THC) and Cannabidiol (CBD) Administration in Healthy Volunteers

Current Pharmaceutical Design September 12, 2012 Rocío Martín‐Santos, José Alexandre S. Crippa, Albert Batalla et al. 288 citations

RATIONALE: Animal and humans studies suggest that the two main constituents of cannabis sativa, delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) have quite different acute effects. However, to date the two compounds have largely been studied separately. OBJECTIVE: To evaluate and compare the acute pharmacological effects of both THC and CBD in the same human volunteers. METHODS: A...

Tolerance and cross-tolerance to neurocognitive effects of THC and alcohol in heavy cannabis users

Psychopharmacology October 30, 2010 Johannes G. Ramaekers, Eef L. Theunissen, Marjolein de Brouwer et al. 168 citations

INTRODUCTION: Previous research has shown that heavy cannabis users develop tolerance to the impairing effects of Δ9-tetrahydrocannabinol (THC) on neurocognitive functions. Animal studies suggest that chronic cannabis consumption may also produce cross-tolerance for the impairing effects of alcohol, but supportive data in humans is scarce. PURPOSE: The present study was designed to assess...

Performance of schizophrenic patients in the Stroop Color Word Test and electrodermal responsiveness after acute administration of cannabidiol (CBD)

Brazilian Journal of Psychiatry March 1, 2010 Jaime E. C. Hallak, João Paulo Machado‐de‐Sousa, José Alexandre S. Crippa et al. 122 citations

OBJECTIVE: The last decade has seen increasing evidence of dysfunctions in the endogenous cannabinoid system in schizophrenia and of its relationship with the typical cognitive impairment of the disorder. Studies in animal models, healthy volunteers, and psychotic patients clearly suggest an antipsychotic-like effect of cannabidiol. This study investigated the effects of cannabidiol on...

Modulation of effective connectivity during emotional processing by Δ9-tetrahydrocannabinol and cannabidiol

The International Journal of Neuropsychopharmacology September 24, 2009 Paolo Fusar‐poli, Paul Allen, Sagnik Bhattacharyya et al. 165 citations

Cannabis sativa, the most widely used illicit drug, has profound effects on levels of anxiety in animals and humans. Although recent studies have helped provide a better understanding of the neurofunctional correlates of these effects, indicating the involvement of the amygdala and cingulate cortex, their reciprocal influence is still mostly unknown. In this study dynamic causal modelling (DCM)...

Neuroimaging in cannabis use: a systematic review of the literature

Psychological Medicine July 23, 2009 Rocío Martín‐Santos, Ana B. Fagundo, José Alexandre S. Crippa et al. 207 citations

BACKGROUND: We conducted a systematic review to assess the evidence for specific effects of cannabis on brain structure and function. The review focuses on the cognitive changes associated with acute and chronic use of the drug. METHOD: We reviewed literature reporting neuroimaging studies of chronic or acute cannabis use published up until January 2009. The search was conducted using Medline,...

Modulation of Mediotemporal and Ventrostriatal Function in Humans by Δ9-Tetrahydrocannabinol

Archives of General Psychiatry April 1, 2009 Sagnik Bhattacharyya, Paolo Fusar‐poli, Stefan Borgwardt et al. 250 citations

CONTEXT: Cannabis sativa use can impair verbal learning, provoke acute psychosis, and increase the risk of schizophrenia. It is unclear where C. sativa acts in the human brain to modulate verbal learning and to induce psychotic symptoms. OBJECTIVES: To investigate the effects of 2 main psychoactive constituents of C. sativa, Delta9-tetrahydrocannabinol (Delta9-THC) and cannabidiol, on regional...

Distinct Effects of Δ9-Tetrahydrocannabinol and Cannabidiol on Neural Activation During Emotional Processing

Archives of General Psychiatry 2009 Paolo Fusar‐poli, José A. Crippa, Sagnik Bhattacharyya et al. 461 citations

CONTEXT: Cannabis use can both increase and reduce anxiety in humans. The neurophysiological substrates of these effects are unknown. OBJECTIVE: To investigate the effects of 2 main psychoactive constituents of Cannabis sativa (Delta9-tetrahydrocannabinol [Delta9-THC] and cannabidiol [CBD]) on regional brain function during emotional processing. DESIGN: Subjects were studied on 3 separate...

Cannabidiol, a Cannabis sativa constituent, as an antipsychotic drug

Brazilian Journal of Medical and Biological Research April 1, 2006 Antônio Waldo Zuardi, José A. Crippa, Jaime E. C. Hallak et al. 411 citations

A high dose of delta9-tetrahydrocannabinol, the main Cannabis sativa (cannabis) component, induces anxiety and psychotic-like symptoms in healthy volunteers. These effects of delta9-tetrahydrocannabinol are significantly reduced by cannabidiol (CBD), a cannabis constituent which is devoid of the typical effects of the plant. This observation led us to suspect that CBD could have anxiolytic...