A scoping review of the use of cannabidiol in psychiatric disorders

The Development of Cannabinoids as Therapeutic Agents in the United States

Cannabis is one of the oldest and widely used substances in the world. Cannabinoids within the cannabis plant, known as phytocannabinoids, mediate cannabis' effects through interactions with the body's endogenous cannabinoid system. This endogenous system, the endocannabinoid system, has important roles in physical and mental health. These roles point to the potential to develop cannabinoids as therapeutic agents while underscoring the risks related to interfering with the endogenous system during nonmedical use. This scoping narrative review synthesizes the current evidence for both the therapeutic and adverse effects of the major (i.e., Δ9-tetrahydrocannabinol and cannabidiol) and lesser studied minor phytocannabinoids, from nonclinical to clinical research. We pay particular attention to the areas where evidence is well established, including analgesic effects after acute exposures and neurocognitive risks after acute and chronic use. In addition, drug development considerations for cannabinoids as therapeutic agents within the United States are reviewed. The proposed clinical study design considerations encourage methodological standards for greater scientific rigor and reproducibility to ultimately extend our knowledge of the risks and benefits of cannabinoids for patients and providers. SIGNIFICANCE STATEMENT: This work provides a review of prior research related to phytocannabinoids, including therapeutic potential and known risks in the context of drug development within the United States. We also provide study design considerations for future cannabinoid drug development.

Cannabidiol Exerts Sedative and Hypnotic Effects in Normal and Insomnia Model Mice Through Activation of 5-HT1A Receptor

Cannabis sativa has been used for improving sleep for long history. Cannabidiol (CBD) has drown much attention as a non-addictive psychoactive component in Cannabis sativa extract. However, the effects of CBD on sleep architecture and it's acting mechanism remains unclear. In the present study, we evaluated the sedative-hypnotic effect of cannabidiol (CBD), assessed the effects of CBD on sleep using a wireless physiological telemetry system. We further explored the therapeutic effects of CBD using 4-chloro-dl-phenylalanine (PCPA) induced insomnia model and changes in sleep latency, sleep duration and intestinal flora were evaluated. CBD shortened sleep latency and increases sleep duration in both normal and insomnia mice, and those effects were blocked by 5-HT1A receptor antagonist WAY100635. We determined that CBD increases 5-HT1A receptors expression and 5-HT content in the hypothalamus of PCPA-pretreated mice and affects tryptophan metabolism in the intestinal flora. These results showed that activation of 5-HT1A receptors is one of the potential mechanisms underlying the sedative-hypnotic effect of CBD. This study validated the effects of CBD on sleep and evaluated its potential therapeutic effects on insomnia.

Cannabidiol usage, efficacy, and side effects: analyzing the impact of health conditions, medications, and cannabis use in a cross-sectional online pilot study

Background

Products containing cannabidiol (CBD) are attracting attention because of their potential therapeutic benefits and positive impacts on well-being and mental health. Although additional research is needed to understand their effectiveness in treating mental disorders, cross-sectional studies may help identify the factors influencing CBD use patterns. This study examined the impact of variables such as health status, medication use, medical supervision, gender, age, and cannabis use on CBD consumption patterns.

Materials and methods

A self-selected sample (n =267) of current or former CBD users was recruited via social media and participated in an online survey designed to collect data on basic demographics, health status, cannabis use, and CBD usage patterns.

Results

The sample (n = 267) consisted of 68.5% women with an average age of 30.21 years, of which 25.8% reported diagnosed psychiatric disorders and 49.4% reported cannabis use. The top five reasons for using CBD were self-reported stress (65.3%), sleep problems (51.7%), overall improvement in well-being (52.5%), improved mood (44.9%), and anxiety relief (40.9%). Our findings suggest that individuals with psychiatric disorders and those taking psychotropic medications are more likely to use CBD to relieve stress and anxiety. Overall, nearly 70% of the individuals found CBD products to be effective. Sublingual administration was more popular among non-cannabis users, while cannabis users preferred smoking and vaping to CBD administration.

Conclusion

Our results indicate that individuals using CBD for health and wellness reasons believe that it has potential health benefits. Further research using rigorous longitudinal designs is needed to delve deeper into the effectiveness of low-dose CBD and to better understand the therapeutic potential of CBD.

An Intravenous Pharmacokinetic Study of Cannabidiol Solutions in Piglets through the Application of a Validated Ultra-High-Pressure Liquid Chromatography Coupled to Tandem Mass Spectrometry Method for the Simultaneous Quantification of CBD and Its Carboxylated Metabolite in Plasma

Cannabidiol (CBD) has multiple therapeutic benefits that need to be maximized by optimizing its bioavailability. Numerous formulations are therefore being developed and their pharmacokinetics need to be studied, requiring analytical methods and data from intravenous administration. As CBD is susceptible to hepatic metabolism, the requirement of any method is to quantify metabolites such as 7-COOH-CBD. We demonstrated that CBD and 7-COOH-CBD could be simultaneously and correctly quantified in piglet plasma by using an UHPLC-MS/MS technique. The validated method allowed for an accurate bioanalysis of an intravenously injected solution consisting of CBD-HPβCD complexes. The experimental pharmacokinetic profile of CBD showed multi-exponential decay characterized by a fast apparent distribution half-life (0.25 h) and an elimination half-life of two hours. The profile of 7-COOH-CBD was not linked with the first-pass metabolism, since 80% of the maximum metabolite concentration was reached at the first sampling time point, without any decrease during the period of study. A two-compartment model was optimal to describe the experimental CBD profile. This model allowed us to calculate macro-micro constants and volumes of distribution (Vss = 3260.35 ± 2286.66 mL) and clearance (1514.5 ± 261.16 mL·h-1), showing that CBD is rapidly distributed to peripheral tissues once injected and slowly released into the bloodstream.

Treatment of Posttraumatic Stress Disorder: A State-of-the-art Review

This narrative state-of-the-art review paper describes the progress in the understanding and treatment of Posttraumatic Stress Disorder (PTSD). Over the last four decades, the scientific landscape has matured, with many interdisciplinary contributions to understanding its diagnosis, etiology, and epidemiology. Advances in genetics, neurobiology, stress pathophysiology, and brain imaging have made it apparent that chronic PTSD is a systemic disorder with high allostatic load. The current state of PTSD treatment includes a wide variety of pharmacological and psychotherapeutic approaches, of which many are evidence-based. However, the myriad challenges inherent in the disorder, such as individual and systemic barriers to good treatment outcome, comorbidity, emotional dysregulation, suicidality, dissociation, substance use, and trauma-related guilt and shame, often render treatment response suboptimal. These challenges are discussed as drivers for emerging novel treatment approaches, including early interventions in the Golden Hours, pharmacological and psychotherapeutic interventions, medication augmentation interventions, the use of psychedelics, as well as interventions targeting the brain and nervous system. All of this aims to improve symptom relief and clinical outcomes. Finally, a phase orientation to treatment is recognized as a tool to strategize treatment of the disorder, and position interventions in step with the progression of the pathophysiology. Revisions to guidelines and systems of care will be needed to incorporate innovative treatments as evidence emerges and they become mainstream. This generation is well-positioned to address the devastating and often chronic disabling impact of traumatic stress events through holistic, cutting-edge clinical efforts and interdisciplinary research.

Using Task-fMRI to Explore the Relationship Between Lifetime Cannabis Use and Cognitive Control in Individuals With First-Episode Schizophrenia

While continued cannabis use and misuse in individuals with schizophrenia is associated with a variety of negative outcomes, individuals with a history of use tend to show higher cognitive performance compared to non-users. While this is replicated in the literature, few studies have used task-based functional magnetic resonance imaging (fMRI) to evaluate whether the brain networks underpinning these cognitive features are similarly impacted. Forty-eight first-episode individuals with schizophrenia (FES) with a history of cannabis use (FES + CAN), 28 FES individuals with no history of cannabis use (FES-CAN), and 59 controls (CON) performed the AX-Continuous Performance Task during fMRI. FES+CAN showed higher cognitive control performance (d'-context) compared to FES-CAN (P < .05, ηp 2 = 0.053), and both FES+CAN (P < .05, ηp 2 = 0.049) and FES-CAN (P < .001, ηp 2 = 0.216) showed lower performance compared to CON. FES+CAN (P < .05, ηp 2 = 0.055) and CON (P < 0.05, ηp 2 = 0.058) showed higher dorsolateral prefrontal cortex (DLPFC) activation during the task compared to FES-CAN, while FES+CAN and CON were not significantly different. Within the FES+CAN group, the younger age of initiation of cannabis use was associated with lower IQ and lower global functioning. More frequent use was also associated with higher reality distortion symptoms at the time of the scan. These data are consistent with previous literature suggesting that individuals with schizophrenia and a history of cannabis use have higher cognitive control performance. For the first time, we also reveal that FES+CAN have higher DLPFC brain activity during cognitive control compared to FES-CAN. Several possible explanations for these findings are discussed.

Consumer perception, knowledge, and uses of cannabidiol

Introduction

The legalization of cannabidiol (CBD) across the United States, in varying degrees, has made CBD easily accessible to consumers for complementary and medical purposes. However, there is a paucity of scientific evidence on the benefits and risks of commercially available CBD. In the literature, 2 studies have gathered consumer perceptions and attitudes on cannabis products, specifically CBD, using survey-based questionnaires. This study aimed to build on the aforementioned studies in obtaining consumer perception and knowledge of CBD products using a national survey-based questionnaire.

Methods

Respondents were recruited through an anonymous, nationwide, online survey administered through Qualtrics in the United States from March 28 to April 30, 2021. The survey consisted of demographics, perceived efficacy and safety of CBD, and resources to obtain CBD information. The survey responses were reported using descriptive statistics along with median and interquartile range for the Likert portion.

Results

A total of 1158 respondents accessed the survey. The median age was 43 and 50% of respondents were female. The uses for CBD included neurological disorders, pulmonary conditions, gastrointestinal disorders, and chronic pain. The most commonly reported safety concern related to taking CBD was anxiety. Participants agreed that CBD is safe when used responsibly for medical use, and social media was the main source used to obtain information about CBD.

Discussion

Respondents who used CBD for a condition thought it was helpful; however, most of the adverse effects were rated as moderate to severe, requiring medical attention from a health care professional, hospital, or emergency room visit.

The Main Therapeutic Applications of Cannabidiol (CBD) and Its Potential Effects on Aging with Respect to Alzheimer's Disease

The use of cannabinoids (substances contained specifically in hemp plants) for therapeutic purposes has received increased attention in recent years. Presently, attention is paid to two main cannabinoids: delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). With respect to the psychotropic effects and dependence potential of THC (though it is very mild), its use is associated with certain restrictions, and thus the therapeutic properties of CBD are frequently emphasized because there are no limitations associated with the risk of dependence. Therefore, this review covers the main pharmacodynamic and pharmacokinetic features of CBD (including characteristics of endocannabinoidome) with respect to its possible beneficial effects on selected diseases in clinical practice. A substantial part of the text deals with the main effects of CBD on aging, including Alzheimer's disease and related underlying mechanisms.

Production challenges of tablets containing lipid excipients: Case study using cannabidiol as drug model

The aims of this study were, firstly, to select an optimal lipid solid dispersion of cannabidiol among different lipid excipients (Gelucire® 50/13, 48/16, 44/14 and Labrasol®) and inorganic carriers (colloidal silica, Syloid® XDP and Neusilin® US2) through a screening plan. The enhancement of aqueous solubility of cannabidiol from a free-flowing powder with adequate drug content was obtained by mixing cannabidiol (20%) with Gelucire® 50/13 (40%; Gattefossé, France), both incorporated inside mesopores of mesoporous silica Syloid® XDP (40%; Grace, Germany). Secondly, we have studied the tableting properties of this selected dispersion through a Design of Experiments (DoE) by manufacturing tablets with other excipients with using a compression simulator (Styl'One® Evo, Medelpharm, France). The design of experiments included the percentage of lipid solid dispersion, of glidant, of lubricant and different compression forces. The dissolution efficiency, the drug content, the tensile strength and the ejection force were analyzed. The DoE showed that % of dispersion as well as compression forces were the main influential variables. An exit of lipid materials outside the mesopores of silica due to compression process has been highlighted, reflected by reduced tensile strength. This study showed the possibility of manufacturing tablets with lipid materials even if limitations have been highlighted. Indeed, the dispersion percentage must not exceed 27% and compression forces up to 13 kN are required to produce lipid tablets with optimal properties.

A Delightful Trip Along the Pathway of Cannabinoid and Endocannabinoid Chemistry and Pharmacology

After a traumatic childhood in Europe during the Second World War, I found that scientific research in Israel was a pleasure beyond my expectations. Over the last 65 year, I have worked on the chemistry and pharmacology of natural products. During the last few decades, most of my research has been on plant cannabinoids, the endogenous cannabinoids arachidonoyl ethanolamide (anandamide) and 2-arachidonoyl glycerol, and endogenous anandamide-like compounds, all of which are involved in a wide spectrum of physiological reactions. Two plant cannabinoids, Δ⁹-tetrahydrocannabinol and cannabidiol, are approved drugs. However, the endogenous cannabinoids and the anandamide-like constituents have not yet been well investigated in humans. For me, intellectual freedom-the ability to do research based on my own scientific interests-has been the most satisfying part of my working life. Looking back over the 91 years of my long life, I conclude that I have been lucky, very lucky, both personally and scientifically.

The Relationship Between Cannabis, Cognition, and Schizophrenia: It's Complicated

The consequences of cannabis use, especially in the context of schizophrenia, have gained increased importance with the legalization of cannabis in North America and across the globe. Cannabis use has multifaceted impacts on cognition in schizophrenia patients and healthy subjects. Healthy subjects, particularly those who initiated cannabis use at earlier ages and used high-potency cannabis for longer durations, exhibited poorer cognition mainly in working memory and attention. Cannabis use in schizophrenia has been associated with symptom exacerbation, longer and more frequent psychotic episodes, and poorer treatment outcomes. However, cannabis-using patients have better overall cognitive performance compared to patients who were not cannabis users. Interestingly, these effects were only apparent in lifetime cannabis users, but not in current (or within last 6 months) users. Moreover, higher frequency and earlier age of cannabis use initiation (i.e., before 17 years of age) were associated with better cognitive performance, although they had an earlier illness onset. Three possible hypotheses seem to come forward to explain this paradox. First, some components of cannabis may have antipsychotic or cognitive-enhancing properties. Secondly, chronic cannabis use may alter endocannabinoid signaling in the brain which could be a protective factor for developing psychosis or cognitive impairments. A third explanation could be their representation of a phenotypically distinct patient group with more intact cognitive functioning and less neurodevelopmental pathology. Multiple factors need to be considered to understand the complex relationship between cannabis, cognitive function, and schizophrenia. In short, age at initiation, duration and rate of cannabis use, abstinence duration, co-use of substances and alcohol, prescribed medications, relative cannabinoid composition and potency of cannabis, presence of genetic and environmental vulnerability factors are prominent contributors to the variability in outcomes. Animal studies support the disruptive effects of Δ9-tetrahydrocannabinol (THC) administration during adolescence on attention and memory performance. They provide insights about interaction of cannabinoid receptors with other neurotransmitter systems, such as GABA and glutamate, and other regulatory molecules, such as PSD95 and synaptophysin. Cannabidiol (CBD), on the other hand, can improve cognitive deficits seen in neurodevelopmental and chemically-induced animal models of schizophrenia. Future studies focusing on bridging the translational gaps between human and animal studies, through the use of translationally relevant methods of exposure (e.g., vaping), consistent behavioral assessments, and congruent circuit interrogations (e.g., imaging) will help to further clarify this complex picture.

Sex Differences in the Neuropsychiatric Effects and Pharmacokinetics of Cannabidiol: A Scoping Review

Cannabidiol (CBD) is a non-intoxicating cannabinoid compound with diverse molecular targets and potential therapeutic effects, including effects relevant to the treatment of psychiatric disorders. In this scoping review, we sought to determine the extent to which sex and gender have been considered as potential moderators of the neuropsychiatric effects and pharmacokinetics of CBD. In this case, 300 articles were screened, retrieved from searches in PubMed/Medline, Scopus, Google Scholar, PsycInfo and CINAHL, though only 12 met our eligibility criteria: eight studies in preclinical models and four studies in humans. Among the preclinical studies, three suggested that sex may influence long-term effects of gestational or adolescent exposure to CBD; two found no impact of sex on CBD modulation of addiction-relevant effects of Δ⁹-tetrahydrocannabinol (THC); two found antidepressant-like effects of CBD in males only; and one found greater plasma and liver CBD concentrations in females compared to males. Among the human studies, two found no sex difference in CBD pharmacokinetics in patient samples, one found greater plasma CBD concentrations in healthy females compared to males, and one found no evidence of sex differences in the effects of CBD on responses to trauma recall in patients with post-traumatic stress disorder (PTSD). No studies were identified that considered the role of gender in CBD treatment effects. We discuss potential implications and current limitations of the existing literature.

Cannabidiol Effect on Cue-Induced Craving for Individuals with Opioid Use Disorder Treated with Buprenorphine: A Small Proof-of-Concept Open-Label Study

Background:

Opioid use disorder (OUD) remains a major public health concern. Despite the use of medications for OUD such as buprenorphine, the current gold-standard treatment, relapse in the context of increased craving remains common. Cannabidiol (CBD) has been shown to reduce cue-induced craving in individuals with OUD, but among those who were not receiving any buprenorphine treatment. This small proof-of-concept open-label study sought to evaluate the effect of CBD on cue-induced craving among individuals with OUD who were being actively treated with buprenorphine.

Methods:

Participants (n = 5) received CBD (Epidiolex^®) 600 mg once daily for 3 consecutive days in an open-label manner. Primary outcome was cue-induced craving measured on a visual analog scale of 0 to 10, calculated as the difference in craving in response to drug-related versus neutral cues. The cue-reactivity paradigm was performed at baseline before CBD administration, and was repeated after 3 days of CBD. Secondary outcomes included scores on depression, anxiety, pain, opioid withdrawal, and side effects.

Results:

All participants were actively taking buprenorphine for an average of 37.8 months (range 1–120 months). Cue-induced craving was significantly lower after CBD dosing compared with baseline (0.4 vs. 3.2, paired t-test, p = 0.0046). No significant changes in scores for depression, anxiety, pain, or opioid withdrawal were noted. CBD was well tolerated, although one participant experienced moderate sedation; otherwise, no other adverse effects were reported.

Conclusions:

Given the high risk for bias in a small uncontrolled open label study such as this, results must be interpreted with caution. A larger adequately powered trial with a suitable control group is needed to confirm the finding that CBD may help to reduce cue-induced craving among individuals with OUD currently on buprenorphine treatment. Research should further evaluate whether adjunctive use of CBD can improve clinical outcomes for individuals with OUD maintained on buprenorphine. ClinicalTrials.gov (NCT04192370).

Cannabinoids and solid organ transplantation: Psychiatric perspectives and recommendations

Cannabinoid use in patients seeking solid organ transplantation (SOT) is an important and unsettled matter which all transplantation clinicians regularly encounter. It is also a multifaceted, interprofessional issue, difficult for any specialty alone to adequately address in a research article or during clinical care. Such uncertainty lends itself to bias for or against cannabinoid use accompanied by inconsistent policies and procedures. Scientific literature in SOT regarding cannabinoids often narrowly examines the issue and exists mostly in liver and kidney transplantation. Published recommendations from professional societies are mosaics of vagueness and specificity mirroring the ongoing dilemma. The cannabinoid information SOT clinicians need for clinical care may require data and perspectives from diverse medical literature which are rarely synthesized. SOT teams may not be adequately staffed or trained to address various neuropsychiatric cannabinoid effects and risks in patients. In this article, authors from US transplantation centers conduct a systematized review of the few existing studies regarding clinician perceptions, use rates, and clinical impact of cannabinoid use in SOT patients; collate representative professional society guidance on the topic; draw from diverse medical literature bases to detail facets of cannabinoid use in psychiatry and addiction pertinent to all transplantation clinicians; provide basic clinical and policy recommendations; and indicate areas of future study.

A Placebo-Controlled Trial of Cannabinoid Treatment for Disruptive Behavior in Children and Adolescents with Autism Spectrum Disorder: Effects on Sleep Parameters as Measured by the CSHQ

Autism spectrum disorder (ASD) is often associated with debilitating sleep disturbances. While anecdotal evidence suggests the positive effect of cannabinoids, randomized studies are lacking. Here, we report the effects of cannabinoid treatment on the sleep of 150 children and adolescents with ASD, as part of a double-blind, placebo-controlled study that assessed the impact of cannabinoid treatment on behavior (NCT02956226). Participants were randomly assigned to one of the following three treatments: (1) whole-plant cannabis extract, containing cannabidiol (CBD) and Δ9-Tetrahydrocannabinol (THC) in a 20:1 ratio, (2) purified CBD and THC extract in the same ratio, and (3) an oral placebo. After 12 weeks of treatment (Period 1) and a 4-week washout period, participants crossed over to a predetermined, second 12-week treatment (Period 2). Sleep disturbances were assessed using the Children’s Sleep-Habit Questionnaire (CSHQ). We found that the CBD-rich cannabinoid treatment was not superior to the placebo treatment in all aspects of sleep measured by the CSHQ, including bedtime resistance, sleep-onset delay, and sleep duration. Notably, regardless of the treatment (cannabinoids or placebo), improvements in the CSHQ total score were associated with improvements in the autistic core symptoms, as indicated by the Social Responsiveness Scale total scores (Period 1: r = 0.266, p = 0.008; Period 2: r = 0.309, p = 0.004). While this study failed to demonstrate that sleep improvements were higher with cannabinoids than they were with the placebo treatment, further studies are required.

Anti-Microbial Activity of Phytocannabinoids and Endocannabinoids in the Light of Their Physiological and Pathophysiological Roles

Antibiotic resistance has become an increasing challenge in the treatment of various infectious diseases, especially those associated with biofilm formation on biotic and abiotic materials. There is an urgent need for new treatment protocols that can also target biofilm-embedded bacteria. Many secondary metabolites of plants possess anti-bacterial activities, and especially the phytocannabinoids of the Cannabis sativa L. varieties have reached a renaissance and attracted much attention for their anti-microbial and anti-biofilm activities at concentrations below the cytotoxic threshold on normal mammalian cells. Accordingly, many synthetic cannabinoids have been designed with the intention to increase the specificity and selectivity of the compounds. The structurally unrelated endocannabinoids have also been found to have anti-microbial and anti-biofilm activities. Recent data suggest for a mutual communication between the endocannabinoid system and the gut microbiota. The present review focuses on the anti-microbial activities of phytocannabinoids and endocannabinoids integrated with some selected issues of their many physiological and pharmacological activities.