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

"Alone in the dark": A qualitative study of treatment experiences among young adults with a recent concussion and anxiety

PURPOSE

Young adults with anxiety are vulnerable to developing persistent symptoms following concussions. In order to develop psychosocial interventions to prevent persistent post-concussion symptoms, we need to understand patients' 1) experiences with treatments offered by health care providers; 2) experiences with attempted concussion management strategies; and 3) needs after their injury.

METHODS

We conducted in-depth interviews with 17 young adults with recent (≤ 10 weeks) concussions who have at least mild anxiety (Generalized Anxiety Disorder Assessment-7 ≥ 5). We used a hybrid deductive-inductive approach to thematic analysis.

RESULTS

Findings provide insight into recommended treatments (e.g., active/avoidant strategies, accommodations, referrals), attempted strategies (e.g., lifestyle changes, pacing, relationships, acceptance-based coping skills), and patient needs (e.g., education, accommodations, referrals for cognitive and emotional skills). Participants frequently expressed that treatment recommendations were confusing and difficult to implement. They initiated non-prescribed strategies that helped promote recovery and expressed a desire for more interdisciplinary treatment and education on concussions.

CONCLUSION

Patients' perceptions of health care provider recommendations after concussions did not fully meet patients' perceived needs. Young adults with concussions and anxiety would benefit from more education, guidance, and psychosocial and rehabilitation services. Addressing these gaps may help align treatments with patients' needs and therefore help optimize their recovery.

Using Smartphone Technology to Track Real-Time Changes in Anxiety/Depression Symptomatology Among Florida Cannabis Users

Objective

Recent scientific attention has focused on the therapeutic effectiveness of cannabis use on a variety of physical and mental ailments. The present study uses smartphone technology to assess self-reported experiences of Florida cannabis users to understand how cannabis may impact anxiety and depression symptomatology.

Method

Several hundred Releaf App™ users from the state of Florida provided anonymous, real-time reports of their symptoms of anxiety and/or depression immediately before and after cannabis use sessions. Linear mixed-effects modeling was used to analyze the data at the symptom and user level.

Results

Results showed that for the majority of users, cannabis use was associated with a significant decrease in depression and anxiety symptomatology. While symptom type, doses per session, consumption method, and CBD levels were significant predictors of relief change, their effect sizes were small and should be interpreted with caution. At the user level, those who had positive relief outcomes in anxiety reported more doses and sessions, and those in the depression group reported more sessions.

Conclusions

Our results generally support the therapeutic effectiveness of cannabis against depression/anxiety symptomatology. Future work should include standardized statistics and effect size estimates for a better understanding of each variable's practical contribution to this area of study.

Effects of cannabidiol, with and without ∆9-tetrahydrocannabinol, on anxiety-like behavior following alcohol withdrawal in mice

Introduction

Alcohol use disorder (AUD) is commonly associated with anxiety disorders and enhanced stress-sensitivity; symptoms that can worsen during withdrawal to perpetuate continued alcohol use. Alcohol increases neuroimmune activity in the brain. Our recent evidence indicates that alcohol directly modulates neuroimmune function in the central amygdala (CeA), a key brain region regulating anxiety and alcohol intake, to alter neurotransmitter signaling. We hypothesized that cannabinoids, such as cannabidiol (CBD) and ∆9-tetrahydrocannabinol (THC), which are thought to reduce neuroinflammation and anxiety, may have potential utility to alleviate alcohol withdrawal-induced stress-sensitivity and anxiety-like behaviors via modulation of CeA neuroimmune function.

Methods

We tested the effects of CBD and CBD:THC (3:1 ratio) on anxiety-like behaviors and neuroimmune function in the CeA of mice undergoing acute (4-h) and short-term (24-h) withdrawal from chronic intermittent alcohol vapor exposure (CIE). We further examined the impact of CBD and CBD:THC on alcohol withdrawal behaviors in the presence of an additional stressor.

Results

We found that CBD and 3:1 CBD:THC increased anxiety-like behaviors at 4-h withdrawal. At 24-h withdrawal, CBD alone reduced anxiety-like behaviors while CBD:THC had mixed effects, showing increased center time indicating reduced anxiety-like behaviors, but increased immobility time that may indicate increased anxiety-like behaviors. These mixed effects may be due to altered metabolism of CBD and THC during alcohol withdrawal. Immunohistochemical analysis showed decreased S100β and Iba1 cell counts in the CeA at 4-h withdrawal, but not at 24-h withdrawal, with CBD and CBD:THC reversing alcohol withdrawal effects..

Discussion

These results suggest that the use of cannabinoids during alcohol withdrawal may lead to exacerbated anxiety depending on timing of use, which may be related to neuroimmune cell function in the CeA.

PTSD, distress and substance use in the aftermath of October 7th, 2023, terror attacks in Southern Israel

The October 7th, 2023, terror attacks in Israel were characterized by a scope and magnitude not previously known to Israeli citizens. The aim of this study was to examine the prevalence and correlates of posttraumatic stress disorder (PTSD), emotional distress and use of addictive substances among Israeli adults, approximately one month following the attacks. PTSD was assessed with the Posttraumatic Stress Disorder Checklist (PCL-5) and emotional distress was assessed with a brief version of the Hopkins Symptom Checklist (HSCL-25). Participants also ranked the degree of change in their frequency of use of six addictive substances. The final sample consisted of 415 Jewish and Arab Israeli adults. Results indicate that one month following the attacks, 31.4% of the total sample qualified for positive screening of PTSD. An increase in the use of tobacco, alcohol, tranquilizers and sleep medications was reported by 16.5%, 10.1%, 11.1% and 10.6% of the sample, respectively. Being at a younger age, of female sex and with increased exposure to the attacks was associated with increased levels of PTSD (β = -0.24, p < 0.001; β = 0.19, p < 0.001 and β = 0.29, p < 0.001, respectively) and increased distress (β = -0.22, p < 0.001, β = 0.26, p < 0.001 and β = 0.19, p < 0.001, respectively). Being male was significantly associated with increased use of cannabis (Adjusted Odds Ratio (AOR) = 4.73, 95% Confidence Interval (CI) = 1.70-13.13, p = 0.003), and level of exposure to traumatic events was significantly associated with increased use of tranquilizers (AOR = 1.58, 95% CI = 1.17-2.13, p = 0.003). The high magnitude of symptomatic response should alert other countries as they prepare for national disasters.

Unveiling the link between chronic pain and misuse of opioids and cannabis

Over 50 million Americans endure chronic pain where many do not receive adequate treatment and self-medicate to manage their pain by taking substances like opioids and cannabis. Research has shown high comorbidity between chronic pain and substance use disorders (SUD) and these disorders share many common neurobiological underpinnings, including hypodopaminergic transmission. Drugs commonly used for self-medication such as opioids and cannabis relieve emotional, bothersome components of pain as well as negative emotional affect that perpetuates misuse and increases the risk of progressing towards drug abuse. However, the causal effect between chronic pain and the development of SUDs has not been clearly established. In this review, we discuss evidence that affirms the proposition that chronic pain is a risk factor for the development of opioid and cannabis use disorders by outlining the clinical evidence and detailing neurobiological mechanisms that link pain and drug misuse. Central to the link between chronic pain and opioid and cannabis misuse is hypodopaminergic transmission and the modulation of dopamine signaling in the mesolimbic pathway by opioids and cannabis. Moreover, we discuss the role of kappa opioid receptor activation and neuroinflammation in the context of dopamine transmission, their contribution to opioid and cannabis withdrawal, along with potential new treatments.

Vaporized D-limonene selectively mitigates the acute anxiogenic effects of Δ9-tetrahydrocannabinol in healthy adults who intermittently use cannabis

BACKGROUND

Cannabis contains hundreds of chemical constituents beyond delta-9-tetrahydrocannabinol (THC), which is believed to drive most of its acute pharmacodynamic effects. The entourage effect theory asserts that non-THC constituents can impact acute cannabis effects, but few empirical studies have systematically evaluated this theory in humans. This study assessed whether the cannabis terpenoid d-limonene mitigates the acute anxiogenic effects of THC.

METHODS

Twenty healthy adults completed nine, double-blind outpatient sessions in which they inhaled vaporized THC alone (15mg or 30mg), d-limonene alone (1mg or 5mg), the same doses of THC and d-limonene together, or placebo; a subset of participants (n=12) completed a tenth session in which 30mg THC+15mg d-limonene was administered. Outcomes included subjective drug effects, cognitive/psychomotor performance, vital signs, and plasma THC and d-limonene concentrations.

RESULTS

When d-limonene was administered alone, pharmacodynamic outcomes did not differ from placebo. Administration of 15mg and 30mg THC alone produced subjective, cognitive, and physiological effects typical of acute cannabis exposure. Ratings of anxiety-like subjective effects qualitatively decreased as d-limonene dose increased and concurrent administration of 30mg THC+15mg d-limonene significantly reduced ratings of "anxious/nervous" and "paranoid" compared with 30mg THC alone. Other pharmacodynamic effects were unchanged by d-limonene. D-limonene plasma concentrations were dose orderly, and concurrent administration of d-limonene did not alter THC pharmacokinetics.

CONCLUSIONS

D-limonene selectively attenuated THC-induced anxiogenic effects, suggesting this terpenoid could increase the therapeutic index of THC. Future research should determine whether this effect extends to oral dose formulations and evaluate the interactions between other cannabis terpenoids or cannabinoids and THC.

Benzodiazepine use in medical cannabis authorization adult patients from 2013 to 2021: Alberta, Canada

BACKGROUND

Benzodiazepines are a class of medications that are being frequently prescribed in Canada but carry significant risk of harm. There has been increasing clinical interest on the potential "sparing effects" of medical cannabis as one strategy to reduce benzodiazepine use. The objective of this study as to examine the association of medical cannabis authorization with benzodiazepine usage between 2013 and 2021 in Alberta, Canada.

METHODS

A propensity score matched cohort study with patients on regular benzodiazepine treatment authorized to use medical cannabis compared to controls who do not have authorization for medical cannabis. A total of 9690 medically authorized cannabis patients were matched to controls. To assess the effect of medical cannabis use on daily average diazepam equivalence (DDE), interrupted time series (ITS) analysis was used to assess the change in the trend of DDE in the 12 months before and 12 months after the authorization of medical cannabis.

RESULTS

Over the follow-up period after medical cannabis authorization, there was no overall change in the DDE use in authorized medical cannabis patients compared to matched controls (- 0.08 DDE, 95% CI: - 0.41 to 0.24). Likewise, the sensitivity analysis showed that, among patients consuming ≤5 mg baseline DDE, there was no change immediately after medical cannabis authorization compared to controls (level change, - 0.04 DDE, 95% CI: - 0.12 to 0.03) per patient as well as in the month-to-month trend change (0.002 DDE, 95% CI: - 0.009 to 0.12) per patient was noted.

CONCLUSIONS

This short-term study found that medical cannabis authorization had minimal effects on benzodiazepine use. Our findings may contribute ongoing evidence for clinicians regarding the potential impact of medical cannabis to reduce benzodiazepine use.

HIGHLIGHTS

• Medical cannabis authorization had little to no effect on benzodiazepine usage among patients prescribed regular benzodiazepine treatment in Alberta, Canada. • Further clinical research is needed to investigate the potential impact of medical cannabis as an alternative to benzodiazepine medication.

Cannabis Dependence is Associated with Reduced Hippocampal Subregion Volumes Independently of Sex: Findings from an ENIGMA Addiction Working Group Multi-Country Study

Background: Males and females who consume cannabis can experience different mental health and cognitive problems. Neuroscientific theories of addiction postulate that dependence is underscored by neuroadaptations, but do not account for the contribution of distinct sexes. Further, there is little evidence for sex differences in the neurobiology of cannabis dependence as most neuroimaging studies have been conducted in largely male samples in which cannabis dependence, as opposed to use, is often not ascertained. Methods: We examined subregional hippocampus and amygdala volumetry in a sample of 206 people recruited from the ENIGMA Addiction Working Group. They included 59 people with cannabis dependence (17 females), 49 cannabis users without cannabis dependence (20 females), and 98 controls (33 females). Results: We found no group-by-sex effect on subregional volumetry. The left hippocampal cornu ammonis subfield 1 (CA1) volumes were lower in dependent cannabis users compared with non-dependent cannabis users (p<0.001, d=0.32) and with controls (p=0.022, d=0.18). Further, the left cornu ammonis subfield 3 (CA3) and left dentate gyrus volumes were lower in dependent versus non-dependent cannabis users but not versus controls (p=0.002, d=0.37, and p=0.002, d=0.31, respectively). All models controlled for age, intelligence quotient (IQ), alcohol and tobacco use, and intracranial volume. Amygdala volumetry was not affected by group or group-by-sex, but was smaller in females than males. Conclusions: Our findings suggest that the relationship between cannabis dependence and subregional volumetry was not moderated by sex. Specifically, dependent (rather than non-dependent) cannabis use may be associated with alterations in selected hippocampus subfields high in cannabinoid type 1 (CB1) receptors and implicated in addictive behavior. As these data are cross-sectional, it is plausible that differences predate cannabis dependence onset and contribute to the initiation of cannabis dependence. Longitudinal neuroimaging work is required to examine the time-course of the onset of subregional hippocampal alterations in cannabis dependence, and their progression as cannabis dependence exacerbates or recovers over time.

Daily associations with cannabis use and sleep quality in anxious cannabis users

INTRODUCTION

Cannabis is increasingly used to self-treat anxiety and related sleep problems, without clear evidence of either supporting or refuting its anxiolytic or sleep aid effects. In addition, different forms of cannabis and primary cannabinoids ∆9-tetrahydrocannabinol (THC) and cannabidiol (CBD) have differing pharmacological effects.

METHODS

Thirty days of daily data on sleep quality and cannabis use were collected in individuals who use cannabis for mild-to-moderate anxiety (n = 347; 36% male, 64% female; mean age = 33 years). Participants self-reported both the form (flower or edible) and the ratio of THC to CBD in the cannabis used during the observation period.

RESULTS

Individuals who reported cannabis use on a particular day also reported better sleep quality the following night. Moderation analyses showed that better perceived sleep after cannabis use days was stronger for respondents with higher baseline affective symptoms. Further, respondents who used cannabis edibles with high CBD concentration reported the highest perceived quality of sleep.

CONCLUSIONS

Among individuals with affective symptoms, naturalistic use of cannabis was associated with better sleep quality, particularly for those using edible and CBD dominant products.

Subjective, behavioral and neurobiological effects of cannabis and cannabinoids in social anxiety

Social anxiety disorder (SAD) is a debilitating disorder, characterized by fear and anxiety in social situations. Evidence suggests that the levels of SAD are rising, in particularly after the COVID-19 pandemic. Serotonin and noradrenaline reuptake inhibitors and cognitive-behavioral therapy are effective treatments for SAD. Nevertheless, a significant number of patients do not respond well to these therapeutic options. During the last years, Cannabis and cannabinoid-containing products have been investigated for the treatment of different neuropsychiatric disorders. Nevertheless, their efficacy for the treatment of anxiety disorders is still a matter of debate. The purpose of this review was to investigate subjective, behavioral, and neurobiological effects of Cannabis and cannabinoids in social anxiety and SAD. A search in the PubMed database for articles published between the years of 2003-2023 was conducted. One hundred and seventeen (117) original studies were identified. After the exclusion criteria, eighteen (18) studies were selected. The studies investigated the effects of the cannabinoids Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) in patients or healthy volunteers submitted to tasks that assessed social anxiety. Results showed that CBD decreases social anxiety, producing an inverted U-shaped curve, with anxiety measurements being reduced at intermediate doses administered orally (300-600 mg), but not at lower or higher doses. THC either reduces (lower doses, 6-7.5 mg) or increases (higher doses) social anxiety measurements. CBD attenuates the anxiogenic effects of THC. The effects of THC and CBD in anxiety are associated to the modulation of fronto-limbic regions. Further clinical trials, conducted with male and female patients and larger cohorts are still necessary to consolidate these results.

Development of cannabidiol derivatives as potent broad-spectrum antibacterial agents with membrane-disruptive mechanism

The emergence of antibiotic resistance has brought a significant burden to public health. Here, we designed and synthesized a series of cannabidiol derivatives by biomimicking the structure and function of cationic antibacterial peptides. This is the first report on the design of cannabidiol derivatives as broad-spectrum antibacterial agents. Through the structure-activity relationship (SAR) study, we found a lead compound 23 that killed both Gram-negative and Gram-positive bacteria via a membrane-targeting mechanism of action with low resistance frequencies. Compound 23 also exhibited very weak hemolytic activity, low toxicity toward mammalian cells, and rapid bactericidal properties. To further validate the membrane action mechanism of compound 23, we performed transcriptomic analysis using RNA-seq, which revealed that treatment with compound 23 altered many cell wall/membrane/envelope biogenesis-related genes in Gram-positive and Gram-negative bacteria. More importantly, compound 23 showed potent in vivo antibacterial efficacy in murine corneal infection models caused by Staphylococcus aureus or Pseudomonas aeruginosa. These findings would provide a new design idea for the discovery of novel broad-spectrum antibacterial agents to overcome the antibiotic resistance crisis.

A Comparison of Mental Health Symptoms among Adults Who Vape Nicotine, Cannabis, or Both

OBJECTIVES

Dual use of combustible cannabis and nicotine is related to worse mental health symptoms (MHS); however, little is known about MHS among those who vape cannabis and nicotine. The current study aimed to determine if dual use of cannabis and nicotine vapes is associated with worse MHS compared to single use and to identify correlates of MHS for dual users.

METHODS

We used Amazon Mechanical Turk to survey adults (N = 492) who used nicotine or cannabis vapes in the past 30 days on stress, anxiety, depression, vape use behaviors and sociodemographic information. We conducted hierarchical linear regressions to compare MHS between dual vs. single substance vape use and to identify correlates of MHS, including sociodemographic variables and vape use characteristics.

RESULTS

The final sample was 37.6% female, 87.6% White, and 11% Hispanic/Latinx with a mean age of 34.15 years. After controlling for sociodemographic characteristics and combustible product use, dual users had significantly higher mean MHS severity than single users. For dual users, younger age and being married were associated with higher symptoms of depression and stress. Holding a medical cannabis card was associated with higher anxiety symptoms.

CONCLUSION

The findings suggest that dual use of cannabis and nicotine vapes is associated with worse MHS severity compared to single substance use.

Efficacy of cannabinoids in neurodevelopmental and neuropsychiatric disorders among children and adolescents: a systematic review

A better understanding of the endocannabinoid system and a relaxation in regulatory control of cannabis globally has increased interest in the medicinal use of cannabinoid-based products (CBP). We provide a systematic review of the rationale and current clinical trial evidence for CBP in the treatment of neuropsychiatric and neurodevelopmental disorders in children and adolescents. A systematic search of MEDLINE, Embase, PsycINFO, and the Cochrane Central Register of Trials was performed to identify articles published after 1980 about CBP for medical purposes in individuals aged 18 years or younger with selected neuropsychiatric or neurodevelopmental conditions. Risk of bias and quality of evidence was assessed for each article. Of 4466 articles screened, 18 were eligible for inclusion, addressing eight conditions (anxiety disorders (n = 1); autism spectrum disorder (n = 5); foetal alcohol spectrum disorder (n = 1); fragile X syndrome (n = 2); intellectual disability (n = 1); mood disorders (n = 2); post-traumatic stress disorder (n = 3); and Tourette syndrome (n = 3)). Only one randomised controlled trial (RCT) was identified. The remaining seventeen articles included one open-label trial, three uncontrolled before-and-after trials, two case series and 11 case reports, thus the risk of bias was high. Despite growing community and scientific interest, our systematic review identified limited and generally poor-quality evidence for the efficacy of CBP in neuropsychiatric and neurodevelopmental disorders in children and adolescents. Large rigorous RCTs are required to inform clinical care. In the meantime, clinicians must balance patient expectations with the limited evidence available.

Cannabis use in the UK: a quantitative comparison of individual differences in medical and recreational cannabis users

There is a paucity of research, especially in the UK, that investigates individual differences in both medical and recreational cannabis users. A cross-sectional survey study design was used to assess recreational cannabis users and medical cannabis users currently living in the UK. Recreational cannabis users were invited to take part via social media. Medical cannabis users were recruited from Sapphire Medical Clinics, London, UK, which provides treatment with prescribed cannabis-based medicinal products. Demographic data and cannabis use frequency, as well as post-traumatic stress disorder symptoms (PCL-5), depression symptoms (Centre for Epidemiological Studies Depression Scale), trait and state anxiety (State-Trait Anxiety Inventory), and cannabis use motives [Comprehensive Marijuana Motives Questionnaire (CMMQ)] were collected. The Chi-square and independent-sample t-tests were used for the comparison of categorical variables and normally distributed continuous variables. Data were analyzed using analyses of variance (ANOVAs) and t-tests. Statistical significance was considered where the value of p was <0.05. The survey was completed by 161 participants. Medical cannabis users were older, consumed cannabis more often, had a higher "Sleep" motive on the CMMQ, and had a higher prevalence in self-reporting current diagnoses of neurological problems, mood disorders, and anxiety disorders (p < 0.05). Recreational cannabis users had higher scores on several motives for use (e.g., "Enjoyment," "Coping," "Experimentation," "Boredom," and "Celebration") and higher state anxiety scores (p < 0.05). The most common motives for cannabis use in both groups were "Enjoyment," "Low Risk," and "Sleep." There were no differences between groups in gender, "Low-Risk" motive, post-traumatic stress disorder symptoms, depression scores, trait anxiety scores, self-reported prevalence of substance use-related disorders, and past consumption of alcohol, tobacco, or caffeine (p > 0.05). The current study not only demonstrates a difference in age and motivations for cannabis consumption between recreational and medical cannabis users but also shows areas of potential overlap, including mental health outcomes, past substance use, and gender. These UK-specific findings indicate that recreational cannabis users experience higher state anxiety, highlighting the need for further evaluation of potential anxiogenic/anxiolytic properties of cannabis. These findings demonstrate the importance of researching individual differences in cannabis users and hold significant implications for future research, clinical practice, and legislation.

Anxiety as a predictor of the age of initiation of tobacco and cannabis use in adolescents and young adults

BACKGROUND

Previous research has shown important links between anxiety and the use of tobacco and cannabis. However, it remains unclear whether anxiety leads youth to start using tobacco and cannabis at an earlier age.

METHODS

Data were drawn from Texas Adolescent Tobacco and Marketing Surveillance System for the years 2019-2021(Waves 9-14). Participants were in 10th-grade, 12th-grade, and two years post-high school at baseline. The outcomes were the age of first use of cigarettes, e-cigarettes, and cannabis. Interval-censoring Cox proportional hazards models were fit to examine the differences in the estimated age of initiation of tobacco and cannabis use by anxiety.

RESULTS

Among the 10th-grade cohort, participants with anxiety had an increased risk of an earlier age of cigarette [AHR = 2.29(1.63-3.23)], e-cigarette [AHR = 1.53(1.17-2.00)], and cannabis [AHR = 1.59(1.23-2.05)] initiation. Among the 12th-grade cohort, participants with anxiety had an increased risk of an earlier age of cigarette [AHR = 1.52(1.21-1.90), e-cigarette [1.25(1.01-1.60)] and cannabis [AHR = 1.35(1.09-1.67] initiation. Among the post-high school cohort, the only significant association found was for cannabis initiation [AHR = 1.33(1.11-1.58). Between ages 18-to-19 years in the 10th-grade cohort, and between ages 20-21 years in the 12th-grade cohort, cumulative incidence of each of the three outcomes initiation doubled among anxious youth.

CONCLUSIONS

This study's findings show that anxiety symptoms can increase the risk of substance use initiation at an earlier age, especially among the youngest adolescent cohort (∼15-to-16-year-olds). These findings highlight the importance of early screening and treatment of anxiety symptoms as a preventive measure to delay or prevent the onset of substance use initiation.

The psychedelic effects of cannabis: A review of the literature

Cannabis and classic psychedelics are controlled substances with emerging evidence of efficacy in the treatment of a variety of psychiatric illnesses. Cannabis has largely not been regarded as having psychedelic effects in contemporary literature, despite many examples of historical use along with classic psychedelics to attain altered states of consciousness. Research into the "psychedelic" effects of cannabis, and delta-9-tetrahydrocannabinol (THC) in particular, could prove helpful for assessing potential therapeutic indications and elucidating the mechanism of action of both cannabis and classic psychedelics. This review aggregates and evaluates the literature assessing the capacity of cannabis to yield the perceptual changes, aversiveness, and mystical experiences more typically associated with classic psychedelics such as psilocybin. This review also provides a brief contrast of neuroimaging findings associated with the acute effects of cannabis and psychedelics. The available evidence suggests that high-THC cannabis may be able to elicit psychedelic effects, but that these effects may not have been observed in recent controlled research studies due to the doses, set, and settings commonly used. Research is needed to investigate the effects of high doses of THC in the context utilized in therapeutic studies of psychedelics aimed to occasion psychedelic and/or therapeutic experiences. If cannabis can reliably generate psychedelic experiences under these conditions, high-THC dose cannabis treatments should be explored as potential adjunctive treatments for psychiatric disorders and be considered as an active comparator in clinical trials involving traditional psychedelic medications.

Sex-Dependent Synergism of an Edible THC: CBD Formulation in Reducing Anxiety and Depressive-like Symptoms Following Chronic Stress

Cannabis has shown therapeutic potential in mood and anxiety-related pathologies. However, the two primary constituents of cannabis, cannabidiol (CBD) and Δ-9-tetrahydrocannabinol (THC) produce distinct effects on molecular pathways in neural circuits associated with affective disorders. Moreover, it has been proposed that the combination of THC: and CBD may have unique synergistic properties. In the present study, the effects of a 1:100 THC: CBD ratio edible formulation were tested in behavioural, neuronal and molecular assays for anxiety and depressive-like endophenotypes. Adult male and female Sprague-Dawley rats were stressed for 14 days. Then, for three weeks, open field, elevated plus maze, light/dark box, social interaction, sucrose preference, and the forced swim test were performed 90 minutes after acute consumption of CBD (30 mg/kg), THC (0.3 mg/kg), or 1:100 combination of THC:CBD. After behavioural tests, in vivo, neuronal electrophysiological analyses were performed in the ventral tegmental area and prefrontal cortex (PFC). Furthermore, western-blot experiments examined the expression of biomarkers associated with mood and anxiety disorders, including protein kinase B (Akt), glycogen synthase kinase-3 (GSK-3), BDNF, mTOR, D1, and D2 receptor in nucleus accumbens (NAc) and PFC.Edible THC:CBD produces significant anxiolytic and antidepressant effects only in stressed male rats. In most cases, the combination of THC and CBD had stronger effects than either phytochemical alone. These synergistic effects are associated with alterations in Akt/GSK3 and D2-R expression in NAc and BDNF expression in PFC. Furthermore, THC:CBD reverses chronic stress-induced alterations in PFC neuronal activity. These findings demonstrate a novel synergistic potential for THC:CBD edible formulations in stress-related pathologies.

Dose-dependent Relationships of Same-day and Typical Substance Use to Sleep Duration in College Cannabis and Alcohol Users: A Multilevel Modeling Approach Using Daily Diary Data

This study characterized how quantities of cannabis and alcohol use affect sleep. Single-day and typical cannabis and alcohol use patterns were considered to assess acute-chronic use interactions. Linear and non-linear associations assessed dose-dependence. College students (n=337; 52% female) provided 11,417 days of data, with up to five time points per day. Daily self-reported sleep duration, cannabis use quantity, and alcohol use quantity were subjected to linear mixed modeling to capture linear and curvilinear associations between single-day and typical use on same-night and typical sleep. Sleep duration (difference between bedtime and waketime) was the outcome. Quantity of cannabis used each day andtypical quantity used across all days were predictors in the cannabis models. Parallel single-day and typical alcohol variables were predictors in the alcohol models. Follow-up analyses excluded days with alcohol-cannabis co-use. Main effects of single-day and typical cannabis quantity on sleep duration were observed when all cannabis-use days were modeled. Higher than typical doses of single-day and typical cannabis were associated with longer sleep durations, but only to a point; at the highest doses, cannabis shortened sleep. A main effect of single-day alcohol quantity and two interactions (single-day use with both linear and curvilinear typical use) on sleep duration were observed when all alcohol-use days were modeled. Greater alcohol consumption on a given day led to shorter same-night sleep, but typically heavier drinkers required higher doses than typically lighter drinkers to experience these adverse effects. Follow-up models suggested alcohol co-use may contribute to the purported sleep-promoting effects of cannabis.

Anxiety Modulation by Cannabinoids-The Role of Stress Responses and Coping

Endocannabinoids were implicated in a variety of pathological conditions including anxiety and are considered promising new targets for anxiolytic drug development. The optimism concerning the potentials of this system for anxiolysis is probably justified. However, the complexity of the mechanisms affected by endocannabinoids, and discrepant findings obtained with various experimental approaches makes the interpretation of research results difficult. Here, we review the anxiety-related effects of the three main interventions used to study the endocannabinoid system: pharmacological agents active at endocannabinoid-binding sites present on both the cell membrane and in the cytoplasm, genetic manipulations targeting cannabinoid receptors, and function-enhancers represented by inhibitors of endocannabinoid degradation and transport. Binding-site ligands provide inconsistent findings probably because they activate a multitude of mechanisms concomitantly. More robust findings were obtained with genetic manipulations and particularly with function enhancers, which heighten ongoing endocannabinoid activation rather than affecting all mechanisms indiscriminately. The enhancement of ongoing activity appears to ameliorate stress-induced anxiety without consistent effects on anxiety in general. Limited evidence suggests that this effect is achieved by promoting active coping styles in critical situations. These findings suggest that the functional enhancement of endocannabinoid signaling is a promising drug development target for stress-related anxiety disorders.

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.

Social Psychopharmacology: Novel Approaches to Treat Deficits in Social Motivation in Schizophrenia

BACKGROUND AND HYPOTHESIS

Diminished social motivation is a negative symptom of schizophrenia and leads to severe functional consequences for many patients suffering from the illness. However, there are no effective medications available to treat this symptom. Despite the lack of approved treatments for patients, there is a growing body of literature on the effects of several classes of drugs on social motivation in healthy volunteers that may be relevant to patients. The aim of this review is to synthesize these results in an effort to identify novel directions for the development of medications to treat reduced social motivation in schizophrenia.

STUDY DESIGN

In this article, we review pharmacologic challenge studies addressing the acute effects of psychoactive drugs on social motivation in healthy volunteers and consider how these findings may be applied to deficits in social motivation in schizophrenia. We include studies testing amphetamines and 3,4-methylenedioxymethamphetamine (MDMA), opioids, cannabis, serotonergic psychedelics, antidepressants, benzodiazepines, and neuropeptides.

STUDY RESULTS

We report that amphetamines, MDMA, and some opioid medications enhance social motivation in healthy adults and may represent promising avenues of investigation in schizophrenia.

CONCLUSIONS

Given the acute effects of these drugs on behavioral and performance-based measures of social motivation in healthy volunteers, they may be particularly beneficial as an adjunct to psychosocial training programs in patient populations. It remains to be determined how these medications affect patients with deficits in social motivation, and in which contexts they may be most effectively administered.

Cannabis Pen-Induced Psychosisin a First-Time Adolescent User

Cannabis is a widely used illicit substance that is historically consumed via smoking, but alternative methods of cannabis consumption have been growing in popularity over the past several decades. One such modality is vaporization, which can appeal specifically to adolescent consumers given these pen devices' ease of concealment, lack of characteristic odor, and marketability. Cannabis products designed for vaping often have higher concentrations of the psychoactive component of cannabis, tetrahydrocannabinol (THC), when compared with traditional cannabis leaf smoking. This can increase the intensity of cannabis-related effects such as analgesia, relaxation, appetite stimulation, and reduced nausea and emesis, but also potentially increases the risk for adverse effects such as dysphoria, and more severely, cannabis-induced psychosis (CIP). Here, we present the case of an adolescent female who was brought after school to our emergency department presenting with symptoms of acute psychosis. Her subsequent workup was effectively normal apart from a urine drug screen positive for THC, which the patient confirmed was due to use of a cannabis pen prior to leaving school that day. This prompted the diagnosis of CIP, which was self-limited and resolved without significant intervention. We use this case to provide the symptomatology and treatment of CIP secondary to cannabis pen use, as well as more broadly discuss the potential implications of cannabis vaping on adolescent neurodevelopment, substance use, and psychiatric comorbidities.

Clinical outcome data of anxiety patients treated with cannabis-based medicinal products in the United Kingdom: a cohort study from the UK Medical Cannabis Registry

RATIONALE

Cannabis-based medicinal products (CBMPs) have been identified as novel therapeutics for generalised anxiety disorder (GAD) based on pre-clinical models; however, there is a paucity of high-quality evidence on their effectiveness and safety.

OBJECTIVES

This study aimed to evaluate the clinical outcomes of patients with GAD treated with dried flower, oil-based preparations, or a combination of both CBMPs.

METHODS

A prospective cohort study of patients with GAD (n = 302) enrolled in the UK Medical Cannabis Registry prescribed oil or flower-based CBMPs was performed. Primary outcomes were changes in generalised anxiety disorder-7 (GAD-7) questionnaires at 1, 3, and 6 months compared to baseline. Secondary outcomes were single-item sleep quality scale (SQS) and health-related quality of life index (EQ-5D-5L) questionnaires at the same time points. These changes were assessed by paired t-tests. Adverse events were assessed in line with CTCAE (Common Terminology Criteria for Adverse Events) v4.0.

RESULTS

Improvements in anxiety, sleep quality and quality of life were observed at each time point (p < 0.001). Patients receiving CBMPs had improvements in GAD-7 at all time points (1 month: difference -5.3 (95% CI -4.6 to -6.1), 3 months: difference -5.5 (95% CI -4.7 to -6.4), 6 months: difference -4.5 (95% CI -3.2 to -5.7)). Thirty-nine participants (12.9%) reported 269 adverse events in the follow-up period.

CONCLUSIONS

Prescription of CBMPs in those with GAD is associated with clinically significant improvements in anxiety with an acceptable safety profile in a real-world setting. Randomised trials are required as a next step to investigate the efficacy of CBMPs.

The Effectiveness and Adverse Events of Cannabidiol and Tetrahydrocannabinol Used in the Treatment of Anxiety Disorders in a PTSD Subpopulation: An Interim Analysis of an Observational Study

Background: Anxiety is a condition for which current treatments are often limited by adverse events (AEs). Components of medicinal cannabis, cannabidiol (CBD) and tetrahydrocannabinol (THC), have been proposed as potential treatments for anxiety disorders, specifically posttraumatic stress disorder (PTSD). Objective: To evaluate quality-of-life outcomes after treatment with various cannabis formulations to determine the effectiveness and associated AEs. Methods: An interim analysis of data collected between September 2018 and June 2021 from the CA Clinics Observational Study. Patient-Reported Outcomes Measurement Information System-29 survey scores of 198 participants with an anxiety disorder were compared at baseline and after treatment with medicinal cannabis. The data of 568 anxiety participants were also analyzed to examine the AEs they experienced by the Medical Dictionary for Regulatory Activities organ system class. Results: The median doses taken were 50.0 mg/day for CBD and 4.4 mg/day for THC. The total participant sample reported significantly improved anxiety, depression, fatigue, and ability to take part in social roles and activities. Those who were diagnosed with PTSD (n = 57) reported significantly improved anxiety, depression, fatigue, and social abilities. The most common AEs reported across the whole participant cohort were dry mouth (32.6%), somnolence (31.3%), and fatigue (18.5%), but incidence varied with different cannabis formulations. The inclusion of THC in a formulation was significantly associated with experiencing gastrointestinal AEs; specifically dry mouth and nausea. Conclusions: Formulations of cannabis significantly improved anxiety, depression, fatigue, and the ability to participate in social activities in participants with anxiety disorders. The AEs experienced by participants are consistent with those in other studies.

Should oncologists trust cannabinoids?

Cannabis enjoyed a "golden age" as a medicinal product in the late 19th, early 20th century, but the increased risk of overdose and abuse led to its criminalization. However, the 21st century have witnessed a resurgence of interest and a large body of literature regarding the benefits of cannabinoids have emerged. As legalization and decriminalization have spread around the world, cancer patients are increasingly interested in the potential utility of cannabinoids. Although eager to discuss cannabis use with their oncologist, patients often find them to be reluctant, mainly because clinicians are still not convinced by the existing evidence-based data to guide their treatment plans. Physicians should prescribe cannabis only if a careful explanation can be provided and follow up response evaluation ensured, making it mandatory for them to be up to date with the positive and also negative aspects of the cannabis in the case of cancer patients. Consequently, this article aims to bring some clarifications to clinicians regarding the sometimes-confusing various nomenclature under which this plant is mentioned, current legislation and the existing evidence (both preclinical and clinical) for the utility of cannabinoids in cancer patients, for either palliation of the associated symptoms or even the potential antitumor effects that cannabinoids may have.

Challenges and considerations for treating PTSD with medicinal cannabis: the Australian clinician's perspective

INTRODUCTION

Preclinical and experimental research have provided promising evidence that medicinal cannabis may be efficacious in the treatment of posttraumatic stress disorder (PTSD). However, implementation of medicinal cannabis into routine clinical therapies may not be straightforward.

AREAS COVERED

In this review, we describe some of the clinical, practical, and safety challenges that must be addressed for cannabis-based treatment of PTSD to be feasible in a real-world setting. These issues are especially prevalent if medicinal cannabis is to be combined with trauma-focused psychotherapy.

EXPERT OPINION

Future consideration of the clinical and practical considerations of cannabis use in PTSD therapy will be essential to both the efficacy and safety of the treatment protocols that are being developed. These issues include dose timing and titration, potential for addiction, product formulation, windows of intervention, and route of administration. In particular, exposure therapy for PTSD involves recall of intense emotions, and the interaction between cannabis use and reliving of trauma memories must be explored in terms of patient safety and impact on therapeutic outcomes.

Zebrafish as an Animal Model in Cannabinoid Research

Cannabinoids are active substances present in plants of the Cannabis genus. Both the Food and Drug Administration (FDA) and European Medicines Agency (EMA) have approved several medicinal products containing natural cannabinoids or their synthetic derivatives for the treatment of drug-resistant epilepsy, nausea and vomiting associated with cancer chemotherapy, anorexia in AIDS patients, and the alleviation of symptoms in patients with multiple sclerosis. In fact, cannabinoids constitute a broad group of molecules with a possible therapeutic potential that could be used in the management of much more diseases than mentioned above; therefore, multiple preclinical and clinical studies on cannabinoids have been carried out in recent years. Danio rerio (zebrafish) is an animal model that has gained more attention lately due to its numerous advantages, including easy and fast reproduction, the significant similarity of the zebrafish genome to the human one, simplicity of genetic modifications, and body transparency during the early stages of development. A number of studies have confirmed the usefulness of this model in toxicological research, experiments related to the impact of early life exposure to xenobiotics, modeling various diseases, and screening tests to detect active substances with promising biological activity. The present paper focuses on the current knowledge of the endocannabinoid system in the zebrafish model, and it summarizes the results and observations from studies investigating the pharmacological effects of natural and synthetic cannabinoids that were carried out in Danio rerio. The presented data support the notion that the zebrafish model is a suitable animal model for use in cannabinoid research.

Women are Taking the Hit: Examining the Unique Consequences of Cannabis Use Across the Female Lifespan

Cannabis use has risen dramatically in recent years due to global decriminalization and a resurgence in the interest of potential therapeutic benefits. While emerging research is shaping our understanding of the benefits and harms of cannabis, there remains a paucity of data specifically focused on how cannabis affects the female population. The female experience of cannabis use is unique, both in the societal context and because of the biological ramifications. This is increasingly important given the rise in cannabis potency, as well as the implications this has for the prevalence of Cannabis Use Disorder (CUD). Therefore, this scoping review aims to discuss the prevalence of cannabis use and CUD in women throughout their lifespan and provide a balanced prospective on the positive and negative consequences of cannabis use. In doing so, this review will highlight the necessity for continued research that goes beyond sex differences.

Cannabis-Induced Anxiety Disorder in the Emergency Department

BACKGROUND

In December 2018, Michigan became the 10th state to legalize marijuana for adults. Since this law took effect, increased availability and use of cannabis in Michigan have led to increased emergency department (ED) visits associated with the drug's psychiatric effects.

OBJECTIVES

To describe cannabis-induced anxiety disorder's prevalence, clinical features, and disposition in a community-based study.

METHODS

This was a retrospective cohort analysis of consecutive patients diagnosed with acute toxicity related to cannabis use (ICD-10 code F12). Patients were seen at seven EDs over a 24-month study period. Data collected included demographics, clinical features, and treatment outcomes in ED patients who met the criteria for cannabis-induced anxiety disorder. This group was compared to a cohort experiencing other forms of acute cannabis toxicity. Chi-squared and t-tests were used to compare these two groups across key demographic and outcome variables.

RESULTS

During the study period, 1135 patients were evaluated for acute cannabis toxicity. A total of 196 patients (17.3%) had a chief complaint of anxiety, and 939 (82.7%) experienced other forms of acute cannabis toxicity, predominantly symptoms of intoxication or cannabis hyperemesis syndrome. Patients with anxiety symptoms had panic attacks (11.7%), aggression or manic behavior (9.2%), and hallucinations (6.1%). Compared to patients presenting with other forms of cannabis toxicity, those with anxiety were likelier to be younger, ingested edible cannabis, had psychiatric comorbidities, or had a history of polysubstance abuse.

CONCLUSIONS

Cannabis-induced anxiety occurred in 17.3% of ED patients in this community-based study. Clinicians must be adept in recognizing, evaluating, managing, and counseling these patients following cannabis exposure.

Opposing retrograde and astrocyte-dependent endocannabinoid signaling mechanisms regulate lateral habenula synaptic transmission

The lateral habenula (LHb) encodes aversive states, and its dysregulation is implicated in neuropsychiatric disorders, including depression. The endocannabinoid (eCB) system is a neuromodulatory signaling system that broadly serves to counteract the adverse effects of stress; however, CB1 receptor signaling within the LHb can paradoxically promote anxiogenic- and depressive-like effects. Current reports of synaptic actions of eCBs in the LHb are conflicting and lack systematic investigation of eCB regulation of excitatory and inhibitory transmission. Here, we report that eCBs differentially regulate glutamatergic and GABAergic transmission in the LHb, exhibiting canonical and circuit-specific inhibition of both systems and an opposing potentiation of synaptic glutamate release mediated via activation of CB1 receptors on astrocytes. Moreover, simultaneous depression of GABA and potentiation of glutamate release increases the net excitation-inhibition ratio onto LHb neurons, suggesting a potential cellular mechanism by which cannabinoids may promote LHb activity and subsequent anxious- and depressive-like aversive states.

Comparing the effects of medical cannabis for chronic pain patients with and without co-morbid anxiety: A cohort study

INTRODUCTION

There is growing evidence on the efficacy of cannabis-based medicinal products (CBMPs) for chronic pain (CP). Due to the interaction between CP and anxiety, and the potential impact of CBMPs on both anxiety and CP, this article aimed to compare the outcomes of CP patients with and without co-morbid anxiety following CBMP treatment.

METHODS

Participants were prospectively enrolled and categorized by baseline General Anxiety Disorder-7(GAD-7) scores, into 'no anxiety'(GAD-7 < 5) and 'anxiety'(GAD-7 ≥ 5) cohorts. Primary outcomes were changes in Brief Pain Inventory Short-Form, Short-form McGill Pain Questionnaire-2, Pain Visual Analogue Scale, Sleep Quality Scale (SQS), GAD-7 and EQ-5D-5L index values at 1, 3 and 6 months.

RESULTS

1254 patients (anxiety = 711; no anxiety = 543) met inclusion criteria. Significant improvements in all primary outcomes were observed at all timepoints (p < 0.050), except GAD-7 in the no anxiety group(p > 0.050). The anxiety cohort reported greater improvements in EQ-5D-5L index values, SQS and GAD-7(p < 0.050), but there were no consistent differences in pain outcomes.

CONCLUSION

A potential association between CBMPs and improvements in pain and health-related quality of life (HRQoL) in CP patients was identified. Those with co-morbid anxiety reported greater improvements in HRQoL.

Multinational Association of Supportive Care in Cancer (MASCC) guidelines: cannabis for psychological symptoms including insomnia, anxiety, and depression

PURPOSE

During the treatment of cancer, 18% of patients use cannabis for symptom management. Anxiety, depression, and sleep disturbances are common symptoms in cancer. A systematic review of the evidence for cannabis use for psychological symptoms in cancer patients was undertaken to develop a guideline.

METHODS

A literature search of randomized trials and systematic reviews was undertaken up to November 12, 2021. Studies were independently assessed for evidence by two authors and then evaluated by all authors for approval. The literature search involved MEDLINE, CCTR, EMBASE, and PsychINFO databases. Inclusion criteria included randomized control trials and systematic reviews on cannabis versus placebo or active comparator in patients with cancer and psychological symptom management (anxiety, depression, and insomnia).

RESULTS

The search yielded 829 articles; 145 from Medline, 419 from Embase, 62 from PsychINFO, and 203 from CCTR. Two systematic reviews and 15 randomized trials (4 on sleep, 5 on mood, 6 on both) met eligibility criteria. However, no studies specifically assessed the efficacy of cannabis on psychological symptoms as primary outcomes in cancer patients. The studies varied widely in terms of interventions, control, duration, and outcome measures. Six of 15 RCTs suggested benefits (five for sleep, one for mood).

CONCLUSION

There is no high-quality evidence to recommend the use of cannabis as an intervention for psychological symptoms in patients with cancer until more high-quality research demonstrates benefit.

Stronger together: Coping behaviours and mental health changes of Canadian adolescents in early phases of the COVID-19 pandemic

BACKGROUND

The impact of the COVID-19 pandemic and consequent public health restrictions on the mental health of adolescents is of global concern. The purpose of this study was to examine how Canadian adolescents coped during the early pandemic and whether different coping methods were associated with changes in mental health from before the pandemic to the early lockdown response.

METHODS

Using two-year linked survey data (2018-2020) from a prospective cohort of secondary school students (n = 3,577), linear regression models were used to examine whether changes in mental health (anxiety [Generalized Anxiety Disorder-7 scale], depression [Center for Epidemiologic Studies Depression 10-item scale Revised], emotion regulation [Difficulties in Emotion Regulation Scale], psychosocial well-being [Flourishing scale]) were related to each coping behaviour.

RESULTS

The most common reported coping behaviours included staying connected with friends online (78.8%), playing video games, watching TV/movies, and/or surfing the internet/social media (76.2%), studying or working on schoolwork (71.0%), and getting exercise (65.2%). The use of positive coping mechanisms during the early pandemic period (e.g., keeping a regular schedule, time with family, time with friends online) was associated with less adverse mental health changes from before to during the early lockdown; whereas, negative coping mechanisms (e.g., spending time alone, eating junk food) were consistently associated with more adverse mental health changes.

CONCLUSION

This study demonstrates the importance of social support and connections with both friends and family, as well as keeping and maintaining a routine, over the pandemic. Interventions supporting positive relationships and engagement in these coping behaviours may be protective for adolescent mental health during disruptive events.

Effects of inhaled cannabis high in Δ9-THC or CBD on the aging brain: A translational MRI and behavioral study

With the recent legalization of inhaled cannabis for medicinal and recreational use, the elderly represents one of the newest, rapidly growing cohorts of cannabis users. To understand the neurobiological effects of cannabis on the aging brain, 19-20 months old mice were divided into three groups exposed to vaporized cannabis containing ~10% Δ9-THC, ~10% CBD, or placebo for 30 min each day. Voxel based morphometry, diffusion weighted imaging, and resting state functional connectivity data were gathered after 28 days of exposure and following a two-week washout period. Tail-flick, open field, and novel object preference tests were conducted to explore analgesic, anxiolytic, and cognitive effects of cannabis, respectively. Vaporized cannabis high in Δ9-THC and CBD achieved blood levels reported in human users. Mice showed antinociceptive effects to chronic Δ9-THC without tolerance while the anxiolytic and cognitive effects of Δ9-THC waned with treatment. CBD had no effect on any of the behavioral measures. Voxel based morphometry showed a decrease in midbrain dopaminergic volume to chronic Δ9-THC followed but an increase after a two-week washout. Fractional anisotropy values were reduced in the same area by chronic Δ9-THC, suggesting a reduction in gray matter volume. Cannabis high in CBD but not THC increased network strength and efficiency, an effect that persisted after washout. These data would indicate chronic use of inhaled cannabis high in Δ9-THC can be an effective analgesic but not for treatment of anxiety or cognitive decline. The dopaminergic midbrain system was sensitive to chronic Δ9-THC but not CBD showing robust plasticity in volume and water diffusivity prior to and following drug cessation an effect possibly related to the abuse liability of Δ9-THC. Chronic inhaled CBD resulted in enhanced global network connectivity that persisted after drug cessation. The behavioral consequences of this sustained change in brain connectivity remain to be determined.

Single cannabidiol administration affects anxiety-, obsessive compulsive-, object memory-, and attention-like behaviors in mice in a sex and concentration dependent manner

RATIONALE

The behavioral effects of cannabidiol (CBD) are understudied, but are important, given its therapeutic potential and widespread use as a natural supplement.

OBJECTIVE

The objective of this study was to test whether a single injection of CBD affected anxiety-like or attention-like behavior, or memory in wildtype mice or mice with reported trait anxiety due to a targeted gene-deletion in a voltage-dependent potassium channel, Kv1.3.

METHODS

Wildtype C57BL/6 J and Kv1.3-/- mice of both sexes were reared to adulthood and then administered an intraperitoneal injection of 10 or 20 mg/kg CBD. Mice were behaviorally-phenotyped using the marble-burying test, the light-dark box (LDB), short (1 h) and long-term (24 h) object memory test, the elevated-plus maze (EPM), and the object-based attention task in order to assess obsessive compulsive-, anxiety-, and attention-like behaviors, and memory.

RESULTS

We discovered that acute CBD treatment reduced marble burying in male, but not female mice. CBD was effective in lessening anxiety-like behaviors determined by the LDB test in both male and female wildtype mice, whereby the effective dose required to observe the effect in females was less. In Kv1.3-/- mice, CBD increased anxiety-like behaviors in the LDB in both sexes at the higher concentration of CBD and it similarly increased anxiety-like behavior in females in the EPM at the lower concentration of CBD. Long-term object memory was reduced in male wildtype mice at the lower concentration of CBD. Finally, ADHD- or attention-like behaviors were not altered by CBD in wildtype mice, but in Kv1.3-/- mice, females were observed to have a loss in attention while males demonstrated improved attention.

CONCLUSIONS

We conclude that administration of a single dose of CBD has immediate effects on mouse behavior that is dose, sex, and anxiety-state dependent - and that these behavioral outcomes are important to examine in parallel human trials.

Improved Post-Traumatic Stress Disorder Symptoms and Related Sleep Disturbances after Initiation of Medical Marijuana Use: Evidence from a Prospective Single Arm Pilot Study

Introduction

Post-traumatic stress disorder (PTSD) is a debilitating disorder experienced by a subgroup of individuals following a life-threatening trauma. Several US states have passed laws permitting the medical use of marijuana (MMJ) by individuals with PTSD, despite very little scientific indication on the appropriateness of marijuana as a therapy for PTSD. This prospective pilot study of adults with confirmed PTSD in Florida (FL) investigated whether PTSD symptoms, sleep quality, affect, and general physical and mental health/well-being improved post-initiation of MMJ treatment.

Methods

Participants, N = 15, were recruited from two MMJ clinics in Gainesville and Jacksonville, FL. To be eligible, participants had to be 18 years of age or older, not currently on MMJ, and willing to abstain from recreational marijuana, if using any, until the State Medical Cannabis Card was obtained, screen positive for PTSD. Participants were assessed at baseline (pre-MMJ initiation) and 30 and 70 days post-MMJ initiation using the Pittsburgh Sleep Quality Index (PSQI), PTSD Checklist for DSM-5 (PCL-5), Positive and Negative Affect Schedule (PANAS), PROMIS Global Health V1.2, and semi-structured marijuana and other substance use assessment.

Results

PTSD symptom severity as measured by total PCL-5 score improved significantly at 30- and 70-day follow-ups. Similarly, statistically significant reductions in nightmares were reported at 30- and 70-day follow-ups. Corresponding improvements in sleep were noticed with participants reporting increased duration of sleep hours, sleep quality, sleep efficiency, and total PSQI score. Likewise, negative affect and global mental health improved significantly at follow-up. According to the post hoc analyses, the most statistically significant changes occurred between baseline and 30-day follow-up. The exception to this pattern was nightmares, which did not show significant improvement until day 70.

Conclusion

The findings of this study highlight the potential of MMJ in improving patient outcomes for those with PTSD, particularly concerning sleep disturbances, which often do not respond to currently available treatments.

THC, CBD, and Anxiety: A review of recent findings on the anxiolytic and anxiogenic effects of cannabis' primary cannabinoids

Purpose of review

In the context of ongoing decriminalization and legalization of cannabis, a better understanding of how THC and CBD impact anxiety is critical to elucidate the risks of recreational cannabis use as well as to establish the therapeutic potential of cannabis products for anxiety-related applications.

Recent findings

Recent literature supports anxiogenic effects of THC administration, which may be attenuated among regular cannabis users. Data regarding anxiolytic effects of CBD administration are mixed. Most newer studies contradict earlier findings in reporting no effects of CBD on anxiety in healthy participants, whereas inconsistent results have been reported among individuals with anxiety disorders, substance use disorders, and other clinical populations.

Summary

Future research is needed to reconcile heterogenous findings, explore sex differences in the effects of THC and CBD on anxiety, as well as to assess how effects change with extended exposure, the impact of different CBD doses, and interactions between THC, CBD, and other cannabis compounds.

Directional associations between cannabis use and anxiety symptoms from late adolescence through young adulthood

BACKGROUND

Two major theories aid in explaining the association between anxiety and cannabis use: a symptom-driven pathway (heightened anxiety precedes greater cannabis use) and a substance-induced pathway (greater use precedes heightened anxiety). Although the co-occurrence of cannabis use and anxiety symptomology is well-established, less is known about the temporal sequence of cannabis use and anxiety symptomology over the course of young adult development METHODS: Data are from an ongoing, longitudinal, cohort study. All prospective analyses used data from wave 8, when participants were between the ages of 17 and 20, through wave 13, when participants are between ages 21 and 24 (N = 2995). Data were set up in accelerated longitudinal design in which we estimated a series of latent difference score models between anxiety and cannabis use from 17 to 24 years old. Models were estimated for men and women, separately.

RESULTS

For the overall sample and men, greater cannabis use predicted greater subsequent increases in anxiety; however, greater anxiety symptoms were associated with decreasing cannabis use. For women, results were more complex. A positive association was noted between prior, trait-like levels of anxiety predicting greater change (increasing) in anxiety symptomology. However, when change is predicted by prior change we see that cannabis use decreases among women who have recently experienced an increase in anxiety CONCLUSION: The nuanced set of results from this study support a dynamic interplay between anxiety symptoms and cannabis use, with important sex differences observed. Overall, our results pave the way for rethinking our guiding theories to include a more robust, flexible, and dynamic model for understanding associations between substance use and mental health symptomology during a key period of development.

Stress- and drug-induced neuroimmune signaling as a therapeutic target for comorbid anxiety and substance use disorders

Stress and substance use disorders remain two of the most highly prevalent psychiatric conditions and are often comorbid. While individually these conditions have a debilitating impact on the patient and a high cost to society, the symptomology and treatment outcomes are further exacerbated when they occur together. As such, there are few effective treatment options for these patients, and recent investigation has sought to determine the neural processes underlying the co-occurrence of these disorders to identify novel treatment targets. One such mechanism that has been linked to stress- and addiction-related conditions is neuroimmune signaling. Increases in inflammatory factors across the brain have been heavily implicated in the etiology of these disorders, and this review seeks to determine the nature of this relationship. According to the "dual-hit" hypothesis, also referred to as neuroimmune priming, prior exposure to either stress or drugs of abuse can sensitize the neuroimmune system to be hyperresponsive when exposed to these insults in the future. This review completes an examination of the literature surrounding stress-induced increases in inflammation across clinical and preclinical studies along with a summarization of the evidence regarding drug-induced alterations in inflammatory factors. These changes in neuroimmune profiles are also discussed within the context of their impact on the neural circuitry responsible for stress responsiveness and addictive behaviors. Further, this review explores the connection between neuroimmune signaling and susceptibility to these conditions and highlights the anti-inflammatory pharmacotherapies that may be used for the treatment of stress and substance use disorders.

An Observational Cross-Sectional Survey Exploring the Indications for and Responses to Medical Marijuana Use in Certified Patients in Pennsylvania

INTRODUCTION/OBJECTIVES

Medical cannabis programs across the country vary and differ in their qualifying conditions for medical cannabis use. This has led to a gap in knowledge regarding the specific needs of cannabis patients, including the most common reason patients seek medical cannabis. The purpose of this study was to examine the current needs of medical cannabis patients in order to better inform future research, and to evaluate potential needs in policy changes in states with more restrictive qualifying conditions for medical cannabis use.

METHODS

A cross-sectional survey study was administered (n = 207) at a Laurel Harvest Labs dispensary in Pennsylvania. Participants were qualified medical cannabis users and were recruited as a convenience sample when entering the dispensary. The survey asked questions regarding participant demographics, medical cannabis qualifying conditions, usage, methods of administration, adverse effects, tolerance, and impact of medical cannabis on medication, alcohol, and tobacco use. Chi-squared or Fisher's exact tests were conducted for analyses involving categorical data.

RESULTS

The mean age of respondents was 36.7 years (SD = 12.8), and the majority were male (61.4%) and white (84.7%). Respondents self-reported that anxiety disorder was the most common qualifying medical condition and the most common comorbid condition (50.1%; 69.3%) for medical cannabis use. Additionally, approximately 95% of users reported having no adverse effects from using medical cannabis, and 90% of users preferred inhalation through vaporization as the preferred method of consumption. More than 50% of participants reported an improvement in their symptoms where only 20% of users reported being tolerant to their current dose. More than 70% of respondents reported that obtaining medical cannabis was "easy" and 54% of users reported that the cost of medical cannabis was not a barrier to access.

CONCLUSIONS

Anxiety disorder is a prevalent condition for which medical cannabis is used; however, many states do not recognize anxiety disorder as a qualifying condition for medical cannabis. Further research on medical cannabis use for anxiety disorders is needed to evaluate proper dosing and responses to treatment.

Survey of Patients Employing Cannabigerol-Predominant Cannabis Preparations: Perceived Medical Effects, Adverse Events, and Withdrawal Symptoms

Introduction: Cannabigerol (CBG), and its precursor before decarboxylation, cannabigerolic acid is sometimes labeled the "mother of all cannabinoids." The purpose of the present study was to investigate reasons for use and self-reported therapeutic effects in CBG-predominant cannabis users. Usage patterns and adverse effects, including withdrawal symptoms were also explored. Methods: Cannabidiol-predominant cannabis users were recruited online to complete an online survey assessing CBG use patterns, conditions treated with CBG-predominant cannabis (containing >50% CBG), perceived efficacy, associated adverse events, and withdrawal symptoms. One hundred twenty-seven eligible participants (U.S. residents ages 21+ who reported using CBG-predominant cannabis in the past 6 months) completed the survey. Results: Most of the samples (n=65; 51.2%) reported use of CBG-predominant products solely for medical purposes (n=46; 36.2% reported use for medical and recreational purposes; n=8; 6.3% reported recreational use only, and n=8 were missing). The most common conditions the complete sample reported using CBG to treat were anxiety (51.2%), chronic pain (40.9%), depression (33.1%), and insomnia/disturbed sleep (30.7%). Efficacy was highly rated, with the majority reporting their conditions were "very much improved" or "much improved" by CBG. Furthermore, 73.9% claimed superiority of CBG-predominant cannabis over conventional medicines for chronic pain, 80% for depression, 73% for insomnia, and 78.3% for anxiety. Forty-four percent of CBG-predominant cannabis users reported no adverse events, with 16.5% noting dry mouth, 15% sleepiness, 11.8% increased appetite, and 8.7% dry eyes. Around 84.3% reported no withdrawal symptoms, with sleep difficulties representing the most frequently endorsed withdrawal symptom (endorsed by two respondents). Conclusions: This is the first patient survey of CBG-predominant cannabis use to date, and the first to document self-reported efficacy of CBG-predominant products, particularly for anxiety, chronic pain, depression, and insomnia. Most respondents reported greater efficacy of CBG-predominant cannabis over conventional pharmacotherapy, with a benign adverse event profile and negligible withdrawal symptoms. This study establishes that humans are employing CBG and suggests that CBG-predominant cannabis-based medicines should be studied in randomized controlled trials.

A survey of medical cannabis use during perimenopause and postmenopause

OBJECTIVE

Expanding access to legal cannabis has dovetailed with increased interest in medical cannabis (MC) use; however, there is a paucity of research examining MC use to alleviate menopause-related symptoms. This survey study assessed patterns of MC use in perimenopausal and postmenopausal individuals.

METHODS

Participants (perimenopausal, n = 131; postmenopausal, n = 127) completed assessments of menopause-related symptomatology and cannabis use, including modes of use, type of use, and menopause-related symptoms addressed by MC use.

RESULTS

Most participants reported current cannabis use (86.1%) and endorsed using MC for menopause-related symptoms (78.7%). The most common modes of use were smoking (84.3%) and edibles (78.3%), and the top menopause-related symptoms for MC use were sleep disturbance (67.4%) and mood/anxiety (46.1%). Relative to postmenopausal participants, perimenopausal participants reported significantly worse menopause-related symptomatology on the vasomotor and psychosocial subscales of the Menopause-Specific Quality of Life Questionnaire ( P s ≤ 0.04), including greater burden of anxiety ( P = 0.01) and hot flash ( P = 0.04) symptoms. In addition, perimenopausal participants reported higher incidence of depression ( P = 0.03) and anxiety diagnoses ( P < 0.01), as well as increased use of MC to treat menopause-related mood/anxiety symptoms relative to postmenopausal participants ( P = 0.01).

CONCLUSIONS

Results suggest that many individuals are currently using MC as an adjunctive treatment for menopause-related symptoms, particularly sleep disturbance and mood/anxiety. Future research should examine the impact of different MC use characteristics (e.g., cannabinoid profiles) on the efficacy of MC use for menopause-related symptoms. Increased severity and prevalence of mood and anxiety symptoms in perimenopausal participants suggest promising targets for clinical trials of cannabinoid-based therapies.

Effects of Cannabis on PTSD Recovery: Review of the Literature and Clinical Insights

Purpose of Review

Individuals with posttraumatic stress disorder (PTSD) may use cannabis to reduce symptoms yet are also at risk for developing problematic use. This review outlines theories, summarizes recent empirical studies, and discusses clinical implications of cannabis use and PTSD recovery.

Recent Findings

Although naturalistic studies and open trials find a relationship between cannabinoids and PTSD symptom reduction, methodological limitations preclude definitive conclusions. The only randomized controlled trial to date found cannabis had no greater effect on PTSD symptoms than placebo.

Summary

Rigorous studies of the long-term impact of cannabis use on PTSD recovery are needed. Clinicians and researchers must weigh the potential therapeutic effect against the costs and risks associated with long-term cannabis use. Clinicians should consider all available PTSD treatment options, along with client level factors such as the function of cannabis use, motivation to change use, and the potential impact of cannabis on treatment engagement when making clinical recommendations.

Cannabinoid Type 1 Receptors in the Basolateral Amygdala Regulate ACPA-Induced Place Preference and Anxiolytic-Like Behaviors

The number of cannabis users is increasing in the world. However, the mechanisms involved in the psychiatric effects and addiction formation remain unclear. Medical treatments against cannabis addiction have not yet been established. Δ9-Tetrahydrocannabinol (THC), the main active substance in cannabis, binds and affects cannabinoid type 1 receptors (CB1R) in the brain. The mice were intraperitoneally (i.p.) administered arachidonylcyclopropylamide (ACPA), a CB1R-selective agonist, and then two behavioral experiments on anxiety and addiction were performed. Administration of ACPA caused anxiolytic-like behavior in the elevated plus maze test. In addition, ACPA increased place preference in a conditioned place preference (CPP) test. The basolateral amygdala (BLA), which is the focus of this study, is involved in anxiety-like behavior and reward and is reported to express high levels of CB1R. We aimed to reveal the role of CB1R in BLA for ACPA-induced behavior. AM251, a CB1R selective antagonist, was administered intra-BLA before i.p. administration of ACPA. Intra-BLA administration of AM251 inhibited ACPA-induced anxiolytic-like behavior and place preference. These results suggest that CB1R in the BLA contributes to behavior disorders caused by the acute or chronic use of cannabis.

Effects of waterpipe tobacco smoke and ceftriaxone treatment on the expression of endocannabinoid receptors in mesocorticolimbic brain regions

Chronic tobacco exposure can alter the endocannabinoid (eCB) system, consequently leading to an anxiety state. In this study, we investigated the effects of waterpipe tobacco smoke (WTS) on cannabinoid receptor 1 and 2 (CBR1 and CBR2) gene and protein expression in mesocorticolimbic brain regions. Using elevated plus maze (EPM) and open field (OF) tests, the effects of WTS exposure on withdrawal-induced anxiety-like behavior were examined. The effect of ceftriaxone (CEF), a β-lactam known to upregulate glutamate transporter 1 (GLT-1), on anxiety and the expression of cannabinoid receptors was also determined. Male Sprague-Dawley rats were randomly assigned to four groups: 1) the Control group was exposed only to standard room air; 2) the WTS group was exposed to tobacco smoke and treated with saline vehicle; 3) the WTS-CEF group was exposed to WTS and treated with ceftriaxone; and 4) the CEF group was exposed only to standard room air and treated with ceftriaxone. Rats were exposed to WTS (or room air) for two hours per day, five days per week for a period of four weeks. Behavioral tests (EPM and OF) were conducted weekly during acute withdrawal, 24 h following WTS exposure. Rats were given either saline or ceftriaxone (200 mg/kg i.p.) for five days during Week 4, 30 min prior to WTS exposure. Withdrawal-induced anxiety was induced by WTS exposure but was reduced by ceftriaxone treatment. WTS exposure decreased CBR1 mRNA and protein expression in the NAc and VTA, but not PFC, and ceftriaxone treatment attenuated these effects. WTS exposure did not change CBR2 mRNA expression in the NAc, VTA, or PFC. These findings demonstrate that WTS exposure dysregulated the endocannabinoid system and increased anxiety-like behavior, and these effects were reversed by ceftriaxone treatment, which suggest the involvement of glutamate transporter 1 in these effects.

Anxiety as a Moderator of the Relationship Between Deviant Peer Association and Substance Use: Does the Specific Dimension of Anxiety Matter?

Deviant peer association has been identified as a risk factor for substance use. Anxiety has been examined as a moderator of this relationship in a limited capacity. Despite this, investigations of specific dimensions of anxiety as moderators of this relationship remain understudied. This study examined three dimensions of anxiety as moderators: physiological anxiety, worry/oversensitivity anxiety, and social concerns/concentration anxiety. The Pathways to Desistance data were used in analyses. Ordered logistic regression models were used to assess relationships of interest for three substance use outcomes: heavy episodic drinking, marijuana use, and cigarette use. Findings indicated that social concerns/concentration anxiety moderated the relationship between deviant peer association and marijuana use, but, contrary to predictions, a protective effect at higher levels of this form of anxiety was observed. Worry/oversensitivity anxiety also appeared to exert a significant and negative direct effect on all three substance use outcomes. Implications are discussed.

Cannabidiol (CBD) in Rheumatic Diseases (Musculoskeletal Pain)

Purpose of Review

This review will address the many uncertainties surrounding the medical use of cannabidiol (CBD). We will begin with an overview of the legal and commercial environment, examine recent preclinical and clinical evidence on CBD, explore questions concerning CBD raised by healthcare professionals and patients, investigate dosing regimens and methods of administration, and address current challenges in the accumulation of sound evidence.

Recent Findings

CBD has potential for relief of symptoms of pain, sleep, and mood disturbance in rheumatology patients, but sound clinical evidence is lacking. CBD is safe when accessed from a regulated source, whereas wellness products are less reliable regarding content and contaminants. Dosing for symptom relief has not yet been established.

Summary

As many rheumatology patients are trying CBD as a self-management strategy, the healthcare community must urgently accrue sound evidence for effect.

Self-Reported Effects of Cannabis on ADHD Symptoms, ADHD Medication Side Effects, and ADHD-Related Executive Dysfunction

OBJECTIVE

People with ADHD are more likely to use cannabis but little is known about the effects of cannabis on ADHD symptoms, ADHD medication side effects, or ADHD-related executive dysfunction.

METHOD

Students (n = 1,738) completed an online survey containing measures of ADHD symptoms, cannabis use, perceived effects of cannabis on ADHD symptoms and medication side effects, as well as executive dysfunction.

RESULTS

Participants with ADHD who have used cannabis reported that cannabis has acute beneficial effects on many symptoms of ADHD (e.g., hyperactivity, impulsivity). Further, they perceived cannabis to improve most of their medication side effects (e.g., irritability, anxiety). Finally, cannabis use frequency was a significant moderator of the associations between symptom severity and executive dysfunction.

CONCLUSION

Results suggest people with ADHD may be using cannabis to self-medicate for many of their symptoms and medication side effects and that more frequent use may mitigate ADHD-related executive dysfunction.

Higher risk, higher reward? Self‐reported effects of real‐world cannabis use in Parkinson's disease

Background

Objective

Methods

Results

Conclusions

Prevalence and self-reported reasons of cannabis use for medical purposes in USA and Canada

RATIONALE

There has been increasing attention on cannabis use for medical purposes, but there is currently a lack of data on its epidemiology.

OBJECTIVES

To examine the epidemiology of self-reported cannabis use for medical purposes by (1) estimating its prevalence, (2) comparing gender and age differences, and (3) investigating what reasons they were used to manage.

METHODS

Participants included 27,169 respondents (aged 16-65) who completed Wave 1 of The International Cannabis Policy Study (ICPS) conducted across Canada and the USA in 2018 via online surveys. Cannabis policy conditions were "US legal-recreational" (legal for both recreational and medical uses), "US legal-medical only", "US illegal", and "Canada-medical only".

RESULTS

The overall prevalence of self-reported ever cannabis use for medical purposes was 27%, with similar rates by sex and the highest prevalence in young adults. Prevalence was higher in US legal-recreational states (34%) than US illegal states (23%), US legal-medical only states (25%), and Canada (25%). The most common physical health reasons include use to manage pain (53%), sleep (46%), headaches/migraines (35%), appetite (22%), and nausea/vomiting (21%). For mental health reasons, the most common were for anxiety (52%), depression (40%), and PTSD/trauma (17%). There were 11% who reported using cannabis for managing other drug or alcohol use and 4% for psychosis.

CONCLUSIONS

A substantial proportion of the North American population self-reported cannabis use for medical purposes for a variety of medical reasons, including those living in jurisdictions without legal markets. Further research is needed to understand the safety and efficacy of these forms of medical cannabis use.