Cannabis use in Europe: Current trends and public health concerns

External hair contamination from cannabis and "light cannabis" delivered by smoking and vaping: An in vitro study

External contamination of hair by cannabis smoking requires a careful evaluation in forensic toxicology. Medical and recreational cannabis are increasingly consumed by e-cigarettes, which give rise to side-stream vapor. Moreover, products containing low Δ9-tetrahydrocannabinol (Δ9-THC) and rich in cannabidiol (CBD) started spreading legally. The goal of the present study was to assess whether hair analysis could allow to distinguish the type of delivered product, with low or high Δ9-THC, and the delivering mode, by smoking or vaping. Contamination of blank hair was mimicked by in vitro exposure to low- (0.4%) and high-Δ9-THC (9.7%) products delivered by smoking and vaping within a small confined system. Cannabis vaping extracts were prepared to deliver identical target Δ9-THC doses. Eighty samples were analyzed by ultrahigh-performance liquid chromatography mass spectrometry and quantified for Δ9-THC and CBD. After contamination by cannabis smoking, THC levels were in line with past in vitro and in vivo studies. Samples exposed to cannabis (169.30 ng/mg) showed significantly higher Δ9-THC than hair exposed to "light cannabis" (35.54 ng/mg), and the opposite was seen for the CBD/Δ9-THC ratio. Hair contaminated by vaping or smoking did not show a statistically different Δ9-THC content. Under our in vitro conditions, hair analysis might allow to discriminate whether external contamination is determined by products containing low or high Δ9-THC, but not the delivering mode. More research is needed in real-life conditions, to see whether the same also applies to the interpretation of forensic casework.

Cannabis-related treatment demand at the eve of German cannabis legalization - a 20-years trend analysis

Post-2000, the prevalence of cannabis consumption has been rising internationally. This paper investigates whether cannabis-related treatment demand in German outpatient addiction care facilities (OACFs) has been following this trend. Treatment demand related to cannabis use disorder (CUD) for the period 2001 to 2021 was investigated using data from the nation-wide standardized German Addiction Care Statistical Service. Analyses covered all and first-time treatment admissions, demographics, and treatment outcomes. We identified years with significant changes in slope or direction of trends through joinpoint regression. Trends within the CUD client population were contrasted with trends among the entire OACF client population. CUD is the second-most common cause for OACF admissions in Germany. Between 2001 and 2021, the share of CUD-related cases among total OACF caseload increased from 7.1 to 19.9%, whereby the share of first-time treatment admissions declined from 79.6 to 55.6%. The share of CUD client population > 35 years almost tripled from 6.0 to 17.4%, that of female client population rose from 15.6 to 18.1%. From 2001 to 2007, the share of CUD-related treatments completed with improved symptomatology increased from 54.7 to 65.6%, followed by a marginal decline. CUD-related treatment demand is growing in Germany's OACFs, involving a client population that is increasingly older and more experienced with the addiction care system. As current intervention programmes mainly target adolescents and young adults who have been consuming cannabis only for a short time, adapting service offers to the changing client profiles appears paramount to improve treatment effectiveness.

Treatment demand for cannabis use problems: analyses of routine data from 30 European countries

Cannabis use and treatment demand has risen in the past decade. Previous analyses of treatment demand are limited by methodological constraints or are outdated. Cross-country differences and trends in cannabis treatment demand are described using data from the European Monitoring Centre for Drugs and Drug Addiction. Two novel indicators are employed: firstly, the cannabis-attributable treatment fraction (CATF) is obtained by dividing the number of treatment entrants for cannabis use problems by the number of treatment entrants for any substance use problem, accounting for possible changes in the reporting system. Secondly, comparing the number of treatment entrants for cannabis use problems to the number of people who use cannabis (near) daily yields the treated-user-ratio (TUR), which considers a proxy for treatment need (frequent use). Across 30 countries with available data, the importance of cannabis in European treatment facilities varies greatly (CATF: min = 3%; max = 65%), with lower estimates in Eastern European countries. Across 20 countries with complete data, the CATF has risen from 29.4% in 2013 to 37.1% in 2020. The TUR calculated on 26 countries suggests that about 3 in 100 frequent users have sought treatment for their cannabis use problems. Over time, treatment demand has increased at a slower pace than treatment need in most countries. One in three treatment entrants for substance use problems in Europe are due to cannabis, with large variations between countries. There are indications for a widening treatment gap for cannabis use problems. In countries liberalising cannabis laws, monitoring changes in treatment access and demand is warranted.

Public Knowledge, Perceptions, and Behavioral Intention Regarding Medical Cannabis in Belgium

Growing evidence on medical cannabis has moved its legislation forward in various countries, which has increased research on stakeholder reactions. While various studies looked at experts and users, research on public perceptions is scarce. This study aims to (1) examine the relationships between knowledge, perceptions, and behavioral intention toward medical cannabis, and (2) identify and profile key segments within the general public. An online survey was conducted among 656 respondents in Belgium. Findings showed that both subjective and objective knowledge are relatively poor, while risk/benefit perceptions and behavioral intention are much more positive. Subjective and objective knowledge as well as social trust have a positive influence on benefit perceptions and a negative influence on risk perceptions. In turn, risk and benefit perceptions are key determinants of behavioral intention, but in opposite directions. Furthermore, cluster analysis identified a cautious (23% of the sample), positive (50%), and enthusiastic cluster (27%). In terms of socio-demographic profile, older and highly educated people were significantly more represented in the latter two clusters. While our study demonstrated that cannabis is well accepted for medical purposes, research is needed to further validate the relationships between knowledge, perceptions, and (intended) behavior in different settings and policy contexts.

Targeting the endocannabinoid system for the management of low back pain

Low back pain (LBP) is a major unmet clinical need. The endocannabinoid system (ECS) has emerged as a promising therapeutic target for pain, including LBP. This review examines the evidence for the ECS as a therapeutic target for LBP. While preclinical studies demonstrate the potential of the ECS as a viable therapeutic target, clinical trials have presented conflicting findings. This review underscores the need for innovative LBP treatments and biomarkers and proposes the ECS as a promising avenue for their exploration. A deeper mechanistic understanding of the ECS in LBP could inform the development of new pain management strategies.

LC-MS/MS analysis of 11-nor-9-carboxy-hexahydrocannabinol (HHC-COOH) and 11-hydroxy-hexahydrocannabinol (HHC-OH) for verification of hexahydrocannabinol (HHC) intake

Natural and semi-synthetic cannabinoid analogs are getting increasing media attention for their recreative use as an alternative to traditional cannabis, in Sweden as well as internationally. To investigate an increasing number of urine samples incoming to our clinical laboratory that were screening positive, using a CEDIA THC-COOH immunoassay from ThermoFisher Scientific, but then testing negative using GC-MS based verification analysis, we developed an LC-MS/MS-method for verification of hexahydrocannabinol (HHC) and Δ8-tetrahydrocannabinol. Assessment of HHC intake was based on identification of the following four metabolites: 11-nor-9(R)-carboxy-hexahydrocannabinol (R-HHC-COOH), 11-nor-9(S)-carboxy-hexahydrocannabinol (S-HHC-COOH), 11-hydroxy-9(R)-hexahydrocannabinol (R-HHC-OH) and 11-hydroxy-9(S)-hexahydrocannabinol (S-HHC-OH). Out of 46 urine samples analysed in this study, 44 showed presence of HHC-metabolites, which indicate HHC as the main explanation for an increased number of negative verifications for THC-COOH. In these samples, the HHC-OH metabolites occurred at a higher concentration than R-HHC-COOH while S-HHC-COOH was only detected in few samples at low concentrations. R-HHC-COOH and S-HHC-COOH can easily be added to a pre-existing verification method for THC-COOH, and still show acceptable results, while HHC-OH requires an enzyme capable of hydrolysing the ether glucuronide bond.

Predictors of effective therapy among individuals with Cannabis Use Disorder: a review of the literature

Treatment demand for Cannabis Use Disorder (CUD) has increased in the past decade in almost all European countries, and CUD is currently the most common reason for first-time drug-related treatment admission in the European Union. Even though several therapeutic approaches have been shown to benefit individuals with CUD, there is a lack of knowledge regarding factors associated with effective therapy and the underlying mechanisms of change among individuals with CUD presenting for treatment. The aim of the present paper was to review current knowledge on factors that have been shown to contribute to positive outcomes in CUD treatment. A scoping methodology was used, focusing on empirically evaluated studies that used defined, cannabis-related outcome measures. In eligible studies, factors of investigation were categorized as either 'mediators', i.e., treatment-related factors associated with the processes or mechanisms through which patients benefit from therapy, or 'moderators' which are patient-related characteristics that predict his/her odds to benefit from treatment or patient-related (i.e., moderators). Factors categorized as mediators were then classified 'specific factors' if they were related to a certain technique or treatment modality or 'common factors' if they were assessed beyond treatment modalities. Findings suggest that in CUD treatment, specific mediators include treatment duration, addressing motivation to change, acquiring coping skills, enhancing self-efficacy, and integrating several therapeutic components. Common mediators include therapeutic alliance, empathy, expectations and cultural adaptation. Moderators in CUD treatment include sex, ethnicity, age-related factors and comorbid disorders.

A call for mindfulness-based interventions for cannabis-use disorders

Cannabis use is being increasingly liberalized worldwide, and an increasing prevalence of cannabis-use disorder (CUD) is observed. The few current therapeutic options for CUD are only modestly effective. Mindfulness-based interventions offer promising prospects for the management of substance-use disorders. However, despite proliferating literature on mindfulness and substance use, few studies have explored mindfulness in terms of cannabis use and CUD. There are many possibilities for the implementation of mindfulness-based interventions for cannabis use reduction, especially for younger users, who are more vulnerable to cannabis-related harms. Accordingly, large controlled trials are needed to reliably assess the potential of such interventions.

A systematic review of oculomotor deficits associated with acute and chronic cannabis use

Driving is a critical everyday task necessitating the rapid and seamless integration of dynamic visually derived information to guide neurobehaviour. Biological markers are frequently employed to detect Δ9-tetrahydrocannabinol (THC) consumption among drivers during roadside tests, despite not necessarily indicating impairment. Characterising THC-specific alterations to oculomotor behaviour may offer a more sensitive measure for indexing drug-related impairment, necessitating discrimination between acute THC effects, chronic use and potential tolerance effects. The present review aims to synthesise current evidence on the acute and chronic effects of THC on driving-relevant oculomotor behaviour. The review was prospectively registered (10.17605/OSF.IO/A4H9W), and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines informed reporting standards. Overall, 20 included articles comprising 12 experimental acute dosing trials, 5 cross-sectional chronic use studies and 3 roadside epidemiological studies examined the effects of cannabis/THC on oculomotor parameters including saccadic activity gaze behaviour, nystagmus, smooth pursuit and eyelid/blink characteristics. Acute THC consumption selectively impacts oculomotor control, notably increasing saccadic latency and inaccuracy and impairing inhibitory control. Chronic cannabis users, especially those with early age of use onset, display enduring oculomotor deficits that affect visual scanning efficiency. The presence of eyelid tremors appears to be a reliable indicator of cannabis consumption while remaining distinct from direct impairment associated with visual attention and motor control. Cannabis selectively influences oculomotor activity relevant to driving, highlighting the role of cannabinoid systems in these processes. Defining cannabis/THC-specific changes in oculomotor control may enhance the precision of roadside impairment assessments and vehicle safety systems to detect drug-related impairment and assess driving fitness.

The impact of cannabis legalization and decriminalization on acute poisoning: A systematic review

BACKGROUND AND AIMS

Many countries have recently legalized medicinal and recreational cannabis. With increasing use and access come the potential for harms. We aimed to examine the effect of cannabis legalization/decriminalization on acute poisoning.

METHODS

A systematic review and meta-analysis registered with PROSPERO (CRD42022323437). We searched Embase, Medline, Scopus and Cochrane Central Register of Controlled Trials from inception to March 2022. No restrictions on language, age or geography were applied. Abstracts from three main clinical toxicology conferences were hand-searched. Included studies had to report on poisonings before and after changes in cannabis legislation, including legalization and decriminalization of medicinal and recreational cannabis. Where possible, relative risk (RR) of poisoning after legalization (versus before) was calculated and pooled. Risk of bias was assessed with ROBINS-I.

RESULTS

Of the 1065 articles retrieved, 30 met inclusion criteria (including 10 conference abstracts). Studies used data from the United States, Canada and Thailand. Studies examined legalization of medicinal cannabis (n = 14) and decriminalization or legalization of recreational cannabis (n = 21). Common data sources included poisons centre records (n = 18) and hospital presentations/admissions (n = 15, individual studies could report multiple intervention types and multiple data sources). Most studies (n = 19) investigated paediatric poisoning. Most (n = 24) reported an increase in poisonings; however, the magnitude varied greatly. Twenty studies were included in quantitative analysis, with RRs ranging from 0.81 to 29.00. Our pooled estimate indicated an increase in poisoning after legalization [RR = 3.56, 95% confidence interval (CI) = 2.43-5.20], which was greater in studies that focused on paediatric patients (RR = 4.31, 95% CI = 2.30-8.07).

CONCLUSIONS

Most studies on the effect of medicinal or recreational cannabis legalization/decriminalization on acute poisoning reported a rise in cannabis poisoning after legalization/decriminalization. Most evidence is from US legalization, despite legalization and decriminalization in many countries.

Usage and health perception of cannabidiol-containing products among the population in Germany: a descriptive study conducted in 2020 and 2021

BACKGROUND

Cannabidiol (CBD), a non-intoxicating substance of Cannabis sativa L., is gaining consumer attention. Yet, legal regulations in the EU are complex and questions of potential health risks remain partly unanswered. In Germany, little is known about people who use CBD products. The aim of this cross-sectional study was to gain insight into the user group of CBD, reasons for consumption and risk perception towards CBD-containing products.

METHODS

The study consisted of two parts: In the first part of the study, the prevalence of CBD awareness and usage in Germany was estimated using a telephone survey and a population-representative sample of n = 1,011 respondents. Based on these results, n = 2,000 participants being aware of CBD were surveyed with an online questionnaire in the second part of the study to examine usage and perception of CBD in users and non-users.

RESULTS

When the study was conducted at the end of 2020 and beginning of 2021, 40.2% of the German participants had already heard of products containing CBD, and 11.4% had actually used them. 42.1% of the users consumed such products regularly, at least once a week, primarily orally via oils or tinctures, and purchased them mainly online. Besides curiosity - addressed especially in young adults - anticipated health benefits including pain and stress relief were main reasons for use. More than half of the study participants perceived the health benefits of CBD use as high or very high. In contrast, the health risks were rated as low or very low by most respondents. Assumptions about official testing for safety as well as physical effects of CBD-containing products varied between users and non-users.

CONCLUSION

About one in nine people in Germany uses CBD-containing products. Given reasons for consumption and perception of potential health risks and benefits suggest that people are insufficiently informed about CBD-containing products. The results of the study indicate that risk communication is needed to raise awareness for the topic and to inform (potential) users.

A cross-sectional survey exploring the knowledge, experiences and attitudes of Australian pharmacists toward medicinal cannabis

BACKGROUND

Australian pharmacists currently dispense a wide range of prescription-only cannabis-based medicines. Recent regulatory changes will expand the role of pharmacists, allowing certain low-dose cannabidiol products to be supplied without a prescription in pharmacies. This harmonises Australia with many other countries where cannabidiol products are readily available to consumers.

AIM

To examine Australian pharmacists' experience, knowledge and attitudes towards medicinal cannabis and their preparedness to supply over-the-counter low-dose cannabidiol products.

METHOD

We conducted a cross-sectional study using a 51-item on-line questionnaire that was informed by previous surveys of health professionals and assessed for face validity. Australian pharmacists were recruited to complete the survey between May and December 2021, primarily through professional pharmacy organisations. Pharmacists were included in the final dataset if they completed the demographic characteristics section and at least one additional section of the questionnaire. Data were analysed using descriptive and relational statistical tests.

RESULTS

There were 272 attempts to complete this survey and 217 responses included in the final dataset. Over half of the respondents (60.0%, 130/217) had dispensed at least one medicinal cannabis prescription during their career and 58.5% (127/217) had received at least one medicinal cannabis enquiry in the last fortnight. Only around half (53.9%, 117/217) felt comfortable supplying medicinal cannabis products and fewer (39.3%, 79/201) were confident discussing cannabis-related enquiries. More than half of the respondents (58.7%, 118/201) supported the provision of low-dose cannabidiol products through pharmacies. Two-thirds (67.8%, 80/118) of respondents achieved relatively low scores (< 60%) in the knowledge component of the survey. Most respondents (94.2%, 178/189) endorsed a need for further training in this area.

CONCLUSION

Australian pharmacists tended to support medicinal cannabis availability and improved access to low-dose cannabidiol products via pharmacies. However, results highlight a need for improved training and education of pharmacists around cannabis-based medicines.

Cannabidiol-associated hepatotoxicity: A systematic review and meta-analysis

BACKGROUND

Findings of liver enzyme elevations in recent cannabidiol studies have raised concerns over liver safety. This study aimed to determine the association between cannabidiol use, liver enzyme elevation, and drug-induced liver injury (DILI).

METHODS

In this systematic review and meta-analysis, a search of EMBASE, CENTRAL, CINAHL, Clinicaltrials.gov, Medline, medRxiv, and Web of Science of records up to February 2022 was conducted. Clinical trials initiating daily cannabidiol treatment with serial liver enzyme measures were included. The proportion of liver enzyme elevations and DILI were independently extracted from published reports. Pooled proportions and probability meta-analyses were conducted.

RESULTS

Cannabidiol use was associated with an increased probability of liver enzyme elevation (N = 12 trials, n = 1229; OR = 5.85 95% CI = 3.84-8.92, p < 0.001) and DILI (N = 12 trials, n = 1229; OR = 4.82 95% CI = 2.46-9.45, p < 0.001) compared to placebo controls. In participants taking cannabidiol (N = 28 trials, n = 1533), the pooled proportion of liver enzyme elevations was 0.074 (95% CI 0.0448-0.1212), and DILI was 0.0296 (95% CI 0.0136-0.0631). High-dose CBD (≥1000 mg/day or ≥20 mg/kg/day) and concomitant antiepileptic drug use were identified as risk factors. No cases were reported in adults using cannabidiol doses <300 mg/day. No cases of severe DILI were reported.

CONCLUSIONS

Cannabidiol-associated liver enzyme elevations and DILI meet the criteria of common adverse drug events. Clinicians are encouraged to screen for cannabidiol use and monitor liver function in patients at increased risk.

Cannabis in Adolescence: Lasting Cognitive Alterations and Underlying Mechanisms

Cannabis consumption during adolescence is an area of particular concern, owing to changes in the social and political perception of the drug, and presents a scientific, medical, and economic challenge. Major social and economic interests continue to push toward cannabis legalization as well as pharmaceutical development. As a result, shifting perceptions of both legal and illicit cannabis use across the population have changed the collective evaluation of the potential dangers of the product. The wave of cannabis legalization therefore comes with new responsibility to educate the public on potential risks and known dangers associated with both recreational and medical cannabis. Among these is the risk of long-term cognitive and psychological consequences, particularly following early-life initiation of use, compounded by high-potency and/or synthetic cannabis, and heavy/frequent use of the drug. Underlying these cognitive and psychiatric consequences are lasting aberrations in the development of synaptic function, often secondary to epigenetic changes. Additional factors such as genetic risk and environmental influences or nondrug toxic insults during development are also profound contributors to these long-term functional alterations following adolescent cannabis use. Preclinical studies indicate that exposure to cannabinoids during specific windows of vulnerability (e.g., adolescence) impacts neurodevelopmental processes and behavior by durably changing dendritic structure and synaptic functions, including those normally mediated by endogenous cannabinoids and neuronal circuits.

Comparison of the Users' Attitudes Toward Cannabidiol on Social Media Platforms: Topic Modeling Study

BACKGROUND

As one of the major constituents of the cannabis sativa plant, cannabidiol (CBD) is approved for use in medical treatment and cosmetics because of its potential health benefits. With the rapid growth of the CBD market, customers purchase these products, and relevant discussions are becoming more active on social media.

OBJECTIVE

In this study, we aimed to understand the users' attitudes toward CBD products in various countries by conducting text mining on social media in countries with different substance management policies.

METHODS

We collected posts from Reddit and Xiaohongshu, conducted topic mining using the latent Dirichlet allocation model, and analyzed the characteristics of topics on different social media. Subsequently, a co-occurrence network of high-frequency keywords was constructed to explore potential relationships among topics. Moreover, we conducted sentiment analysis on the posts' comments and compared users' attitudes toward CBD products on Reddit and Xiaohongshu using chi-square test.

RESULTS

CBD-related posts on social media have been rapidly increasing, especially on Xiaohongshu since 2019. A total of 1790 posts from Reddit and 1951 posts from Xiaohongshu were included in the final analysis. The posts on the 2 social media platforms, Reddit and Xiaohongshu, were categorized into 7 and 8 topics, respectively, by the latent Dirichlet allocation model, and these topics on the 2 social media were grouped into 5 themes. Our study showed that the themes on Reddit were mainly related to the therapeutic effects of CBD, whereas the themes on Xiaohongshu concentrated on cosmetics, such as facial masks. Theme 2 (CBD market information) and theme 3 (attitudes toward CBD) on Reddit had more connections with other themes in the co-occurrence network, and theme 3 and theme 1 (CBD therapeutic effects) had a high co-occurrence frequency (22,803/73,865, 30.87%). Meanwhile, theme 1 (CBD cosmetics) on Xiaohongshu had various connections with others (169,961/384,575, 44.19%), and the co-occurrence frequency of theme 4 (CBD ingredients) and theme 1 was relatively prominent (27,128/49,312, 55.01%). Overall, users' comments tended to be positive for CBD-related information on both Reddit and Xiaohongshu, but the percentage was higher on Xiaohongshu (82.25% vs 86.18%; P<.001), especially in cosmetics and medical health care products.

CONCLUSIONS

The CBD market has grown rapidly, and the topics related to CBD on social media have become active. There are apparent differences in users' attitudes toward CBD in countries with different substance management policies. Targeted CBD management measures should be formulated to suit the prevalence of CBD use of each country.

Effects of cannabidiol on simulated driving and cognitive performance: A dose-ranging randomised controlled trial

BACKGROUND

Cannabidiol (CBD), a major cannabinoid of Cannabis sativa, is widely consumed in prescription and non-prescription products. While CBD is generally considered 'non-intoxicating', its effects on safety-sensitive tasks are still under scrutiny.

AIM

We investigated the effects of CBD on driving performance.

METHODS

Healthy adults (n = 17) completed four treatment sessions involving the oral administration of a placebo, or 15, 300 or 1500 mg CBD in a randomised, double-blind, crossover design. Simulated driving performance was assessed between ~45-75 and ~210-240 min post-treatment (Drives 1 and 2) using a two-part scenario with 'standard' and 'car following' (CF) components. The primary outcome was standard deviation of lateral position (SDLP), a well-established measure of vehicular control. Cognitive function, subjective experiences and plasma CBD concentrations were also measured. Non-inferiority analyses tested the hypothesis that CBD would not increase SDLP by more than a margin equivalent to a 0.05% blood alcohol concentration (Cohen's d_z = 0.50).

RESULTS

Non-inferiority was established during the standard component of Drive 1 and CF component of Drive 2 on all CBD treatments and during the standard component of Drive 2 on the 15 and 1500 mg treatments (95% CIs < 0.5). The remaining comparisons to placebo were inconclusive (the 95% CIs included 0 and 0.50). No dose of CBD impaired cognition or induced feelings of intoxication (ps > 0.05). CBD was unexpectedly found to persist in plasma for prolonged periods of time (e.g. >4 weeks at 1500 mg).

CONCLUSION

Acute, oral CBD treatment does not appear to induce feelings of intoxication and is unlikely to impair cognitive function or driving performance (Registration: ACTRN12619001552178).

Cannabis-related allergies: An international overview and consensus recommendations

Cannabis is the most widely used recreational drug in the world. Cannabis sativa and Cannabis indica have been selectively bred to develop their psychoactive properties. The increasing use in many countries has been accelerated by the COVID-19 pandemic. Cannabis can provoke both type 1 and type 4 allergic reactions. Officially recognized allergens include a pathogenesis-related class 10 allergen, profilin, and a nonspecific lipid transfer protein. Other allergens may also be relevant, and recognition of allergens may vary between countries and continents. Cannabis also has the potential to provoke allergic cross-reactions to plant foods. Since cannabis is an illegal substance in many countries, research has been hampered, leading to challenges in diagnosis since no commercial extracts are available for testing. Even in countries such as Canada, where cannabis is legalized, diagnosis may rely solely on the purchase of cannabis for prick-to-prick skin tests. Management consists of avoidance, with legal issues hindering the development of other treatments such as immunotherapy. Education of healthcare professionals is similarly lacking. This review aimed to summarize the current status of cannabis allergy and proposes recommendations for the future management of this global issue.

The endocannabinoids anandamide and 2-arachidonoylglycerol modulate the expression of angiogenic factors on HTR8/SVneo placental cells

The interest on the endocannabinoid system (ECS) in human reproduction has grown due to its involvement in placenta development, which led to growing concerns over pregnant cannabis consumer's impact on pregnancy outcome. The endocannabinoids anandamide (AEA) and 2-arachidonoylglycerol (2-AG) modulate placental trophoblast proliferation and apoptosis. However, their role on other placentation events such as angiogenesis and invasion are unknown. Using the human extravillous trophoblast HTR-8/SVneo cells, a well-accepted model of first trimester extravillous trophoblast (EVT), this study aims to investigate whether AEA and 2-AG can modulate the expression of angiogenesis- and invasion-related factors. Transcript analysis of angiogenic factors of the vascular endothelial growth factor (VEGF) and matrix metalloproteinase (MMP) protein family demonstrated the ability of AEA to increase VEGF-C and VEGFR3 expression via cannabinoid receptors CB1 and CB2 while the placental growth factor (PlGF) was increased through CB1. Moreover, an increase in VEGFR1, sFLT1, VEGFR2, MMP-2 and TIMP-1 independent of cannabinoid receptor activation was verified. However, 2-AG only increased PlGF transcript through CB1/CB2 activation. Both endocannabinoids stimulated HTR8/SVneo endothelial-like tube formation. As for the wound healing assay, only 2-AG was able to increase the percentage of wound closure. Moreover, the data demonstrated that both AEA and 2-AG, via cannabinoid receptors, activated the STAT3 signaling pathway. Distinct effects were observed on transcription factor HIF-1α and AKT phosphorylation that decreased with both endocannabinoids. Although different angiogenic and migration factors are affected the results obtained in this work showcase once more the ability of the endocannabinoids to modulate key processes in placental physiology.

Cannabis Use, Use Motives and Cannabis Use Disorder Among Berlin College Students

This study described cannabis use behavior among college students in Berlin, in particular, differences in use motives between subjects with frequent use and those with signs of cannabis use disorder (CUD). Cross-sectional data were collected via an online survey among Berlin college students ( N=9350; 50.7% women; Mage=24.4). Motivation scales were computed based on an exploratory factor analysis. Effects of these motive scales were compared using multivariate regression models, where the dependent variable was use intensity (ordinal), frequent use (twice or more per week, binary) or a positive substance use disorder screening test (binary). Cannabis use is known to be particularly prevalent among Berlin college students, which was confirmed by our data. The most frequent use motive was enhancement, which, however, was not associated with frequent use or CUD. The motives predicting frequent use (sociability) are different from motives predicting CUD (coping), even when controlling for a wide array of covariates.

Cannabis-Based Products for the Treatment of Skin Inflammatory Diseases: A Timely Review

The use of natural products in dermatology is increasingly being pursued due to sustainability and ecological issues, and as a possible way to improve the therapeutic outcome of chronic skin diseases, relieving the burden for both patients and healthcare systems. The legalization of cannabis by a growing number of countries has opened the way for researching the use of cannabinoids in therapeutic topical formulations. Cannabinoids are a diverse class of pharmacologically active compounds produced by Cannabis sativa (phytocannabinoids) and similar molecules (endocannabinoids, synthetic cannabinoids). Humans possess an endocannabinoid system involved in the regulation of several physiological processes, which includes naturally-produced endocannabinoids, and proteins involved in their transport, synthesis and degradation. The modulation of the endocannabinoid system is a promising therapeutic target for multiple diseases, including vascular, mental and neurodegenerative disorders. However, due to the complex nature of this system and its crosstalk with other biological systems, the development of novel target drugs is an ongoing challenging task. The discovery of a skin endocannabinoid system and its role in maintaining skin homeostasis, alongside the anti-inflammatory actions of cannabinoids, has raised interest in their use for the treatment of skin inflammatory diseases, which is the focus of this review. Oral treatments are only effective at high doses, having considerable adverse effects; thus, research into plant-based or synthetic cannabinoids that can be incorporated into high-quality, safe topical products for the treatment of inflammatory skin conditions is timely. Previous studies revealed that such products are usually well tolerated and showed promising results for example in the treatment of atopic dermatitis, psoriasis, and contact dermatitis. However, further controlled human clinical trials are needed to fully unravel the potential of these compounds, and the possible side effects associated with their topical use.

Adulteration of low-THC products with synthetic cannabinoids: Results from drug checking services

Since late 2019, low‐delta‐9‐tetrahydrocannabinol (THC) preparations adulterated with synthetic cannabinoids (SCs) have been frequently observed in Switzerland. The unawareness of users concerning the presence of SCs and the typically higher potency and toxicity of SCs, when compared with THC, can result in increased health risks. In Switzerland, low‐THC (<1%) cannabis products, except hashish, are legal. These products can act as carrier materials for SCs. In this study, cannabis samples and user self‐reports received through three drug checking services were collected and analysed, to gain deeper insight into this new phenomenon. Samples were collected from January 2020 to July 2021. Liquid chromatography coupled with high‐resolution mass spectrometry was used for the qualitative screening and semi‐quantification of SCs, while gas chromatography with flame ionization detector was applied for the quantification of THC and cannabidiol levels. Reported adverse effects were compared between users who consumed adulterated (SC‐group) and non‐adulterated (THC‐group) products. Of a total 94 samples, 50% contained up to three different SCs. MDMB‐4en‐PINACA was most often detected. All adulterated cannabis flowers contained ≤1% THC. Adulterated hashish also typically presented low THC‐levels (median: 0.8%). The SC‐group was associated with higher numbers of adverse events (p = 0.041). Furthermore, psychologic (p = 0.0007) and cardiologic (p = 0.020) adverse effects were more profound in the SC‐group than in the THC‐group. Drug checking services enabled the timely detection and monitoring of new and potentially dangerous trends. Furthermore, due to user‐reports, additional valuable information was gained on adverse events associated with the consumption of novel SCs.

Frustrative nonreward and cannabinoid receptors: Chronic (but not acute) WIN 55,212-2 treatment increased resistance to change in two reward downshift tasks

Assessing the role of cannabinoid (CB) receptors in behavior is relevant given the trend toward the legalization of medicinal and recreational marijuana. The present research aims at bridging a gap in our understanding of CB-receptor function in animal models of frustrative nonreward. These experiments were designed to (1) determine the effects of chronic administration of the nonselective CB1-receptor agonist WIN 55,212-2 (WIN) on reward downshift in rats and (2) determine whether the effects of chronic WIN were reducible to acute effects. In Experiment 1, chronic WIN (7 daily injections, 10 mg/kg, ip) accelerated the recovery of consummatory behavior after a 32-to-4% sucrose downshift relative to vehicle controls. In addition, chronic WIN eliminated the preference for an unshifted lever when the other lever was subject to a 12-to-2 pellet downshift in free-choice trials, but only in animals with previous experience with a sucrose downshift. In Experiment 2, acute WIN (1 mg/kg, ip) reduced consummatory behavior, but did not affect recovery from a 32-to-4% sucrose downshift. The antagonist SR 141716A (3 mg/kg, ip) also failed to interfere with recovery after the sucrose downshift. In Experiment 3, acute WIN administration (1 mg/kg, ip) did not affect free-choice behavior after a pellet downshift, although it reduced lever pressing and increased magazine entries relative to vehicle controls. The effects of chronic WIN on frustrative nonreward were not reducible to acute effects of the drug. Chronic WIN treatment in rats, like chronic marijuana use in humans, seems to increase resistance to the effects of frustrative nonreward.

A History of Childhood Maltreatment Has Substance- and Sex-Specific Effects on Craving During Treatment for Substance Use Disorders

RATIONALE

Childhood maltreatment (CM) leads to detrimental mental health outcomes, such as substance use disorders (SUD). This study examined prevalence and severity of all five types of CM with respect to specific substances and sex in treatment-seeking individuals with SUD. The influences of type of CM and symptoms of depressiveness, anxiety, and perceived stress on substance craving at admission as well as craving reduction during SUD treatment were examined.

METHODS

N = 546 patients in treatment for SUD and N = 109 individuals in opioid maintenance treatment filled out questionnaires regarding CM (Childhood Trauma Questionnaire) and psychopathologies. Substance craving was assessed throughout treatment using the Mannheim Craving Scale. Group differences in CM, type of substance and sex were examined. General linear models were applied to examine influences on substance craving.

RESULTS

Higher prevalence and severity of all five subtypes of CM were observed in individuals with SUD compared to the general population. Women were more severely affected by emotional and sexual abuse than men. Patients with cannabis use disorder reported more severe experiences of emotional abuse compared to all other substances. Craving at admission to treatment was influenced by emotional abuse, however, symptoms of depressiveness, anxiety, and perceived stress contributed to craving at admission or craving reduction during treatment.

CONCLUSION

CM relates to SUD and should be incorporated in prevention and treatment of SUD. Underlying mechanisms of the association might relate to impairments in processing and regulation of stress, emotions, and interpersonal relations following a history of CM.

Recreational Cannabidiol: Awareness, Prevalence of use, and Associated Factors in a Representative Sample of the German Population

BACKGROUND

Recreational cannabidiol (CBD) is frequently promoted as a medicinal or therapeutic cannabis product worldwide. Nationwide population-based data on awareness and use of recreational CBD are currently lacking.

OBJECTIVE

This study estimates the prevalence of recreational CBD awareness and use among the population in Germany. It also explores potential associations with socio-demographic characteristics, tobacco smoking, and e-cigarette use.

METHODS

We used data from a cross-sectional household survey (German Study on Tobacco Use, DEBRA) fielded across two waves in October-November 2020 and February-March 2021. Data were collected using computer-assisted face-to-face interviews among participants aged ≥14 years (n = 4026). Outcome variables were CBD awareness (yes/no) and CBD ever use (yes/no). The sample was weighted to ensure representativeness of the prevalence estimates. Associations with socio-demographic variables, tobacco smoking, and e-cigarette use were assessed using multivariable logistic regression.

RESULTS

Approximately half of the population in Germany (48.3%, 95% CI: 46.8-49.9) was aware of recreational CBD products, and 4.3% (95% CI: 3.7-5.0) had ever used them (including 1.1% current users). Awareness was associated with younger age, higher education levels, female sex, living in urban regions, no migration background, tobacco smoking, and e-cigarette use. Ever use was associated with higher education levels, living in urban regions, tobacco smoking, and e-cigarette use.

CONCLUSIONS

Awareness of recreational CBD products is high but ever use is currently low in Germany. Given the uncertain legal framework regarding the marketing of recreational CBD products, the changing retail landscape, and potential harms of CBD use, structured monitoring is warranted for public health purposes.

A "Good" Smoke? The Off-Label Use of Cannabidiol to Reduce Cannabis Use

BACKGROUND

Although cannabis use is common in France, it is still criminalized. Cannabidiol (CBD) products, including CBD-rich cannabis, are legally available. Although previous results suggested that CBD may have benefits for people with cannabis use disorder, there is a lack of data on cannabis users who use CBD to reduce their cannabis consumption. We aimed to identify (i) correlates of this motive, and (ii) factors associated with successful attempts to reduce cannabis use.

METHODS

A cross-sectional online survey among French-speaking CBD and cannabis users was conducted. Logistic regressions were performed to identify correlates of using CBD to reduce cannabis consumption and correlates of reporting a large reduction.

RESULTS

Eleven percent (n = 105) of our study sample reported they primarily used CBD to reduce cannabis consumption. Associated factors included smoking tobacco cigarettes (adjusted odds ratio (aOR) [95% confidence interval (CI)] 2.17 [1.3-3.62], p = 0.003) and drinking alcohol (aOR [95%CI] 1.8 [1.02-3.18], p = 0.042). Of these 105, 83% used CBD-rich cannabis to smoke, and 58.7% reported a large reduction in cannabis consumption. This large reduction was associated with non-daily cannabis use (aOR [95%CI] 7.14 [2.4-20.0], p < 0.001) and daily CBD use (aOR [95%CI] 5.87 [2.09-16.47], p = 0.001). A reduction in cannabis withdrawal symptoms thanks to CBD use was the most-cited effect at play in self-observed cannabis reduction.

CONCLUSIONS

Cannabis use reduction is a reported motive for CBD use-especially CBD-rich cannabis to smoke-in France. More studies are needed to explore practices associated with this motive and to accurately assess CBD effectiveness.

Public health monitoring of cannabis use in Europe: prevalence of use, cannabis potency, and treatment rates

Background

Cannabis is one of the most widely used substances worldwide. Heavy use is associated with an increased risk of cannabis use disorders, psychotic disorders, acute cognitive impairment, traffic injuries, respiratory problems, worse pregnancy outcomes, and there are indications for genotoxic and epigenotoxic adverse effects. International regulation of medical and non-medical cannabis use is changing rapidly and substantially, highlighting the importance of robust public health monitoring. This study aimed to describe the trends of key public health indicators in European Union (27 member states + UK, Norway and Turkey) for the period 2010 to 2019, their public health implications, and to identify the steps required to improve current practice in monitoring of cannabis use and harm in Europe.

Methods

Data on four key cannabis indicators (prevalence of use, prevalence of cannabis use disorder [CUD], treatment rates, and potency of cannabis products) in Europe were extracted from the United Nations Office on Drugs and Crime, European Monitoring Centre for Drugs and Drug Addiction and the Global Burden of Disease study. For prevalence of use and CUD, the first and last available estimate in each country were compared. For treatment rates and cannabis potency, linear regression models were conducted.

Findings

Between 2010 and 2019, past-month prevalence of cannabis use increased by 27% in European adults (from 3·1 to 3·9%), with most pronounced relative increases observed among 35-64 year-olds. In 13 out of 26 countries, over 20% of all past-month users reported high-risk use patterns. The rate of treatment entry for cannabis problems per 100,000 adults increased from 27·0 (95% CI: 17·2 to 36·8) to 35·1 (95% CI: 23·6 to 46·7) and has mostly plateaued since 2015. Modest increases in potency were found in herbal cannabis (from 6·9% to 10·6% THC) while median THC values tripled in cannabis resin (from 7·6% to 24·1% THC).

Interpretation

In the past decade, cannabis use, treatment rates and potency levels have increased in Europe highlighting major concerns about the public health impact of cannabis use. Continued monitoring and efforts to improve data quality and reporting, including indicators of high-risk use and cannabis-attributable harm, will be necessary to evaluate the health impact of international changes in cannabis regulation.

Funding

This study received no specific funding.

Psychotherapeutic interventions for cannabis use disorder. What do we know and what should we do?

BACKGROUND

Cannabis use disorder is the most commonly reported illegal substance use disorder and demand for treatment is growing worldwide.

OBJECTIVES

Our aim was to compare the two last Cochrane systematic reviews of the literature concerning psychotherapeutic and psychosocial interventions for cannabis use disorder to determine what new evidence emerged and how craving was considered as a treatment mediator.

METHOD

We extracted raw data from both reviews regarding their titles, objectives, methods and results. This information was analyzed by face validity to distinguish apparent differences from real differences. It enabled us to describe similarities and differences between reviews. We also screened both reviews looking for craving or related words.

RESULTS

The objective and methods of both reviews were mostly similar. Although the second review covered a wider range of psychotherapies, including drug counseling and mindfulness-based meditation as an intervention group and minimal treatment as a control group. Five of the six studies included in the first review were also included in the second review. One study excluded from the first review was included in the last review that included an additional 17 studies published after the first review. The 2016 review performed a meta-analysis whereas the first review was descriptive. Both reviews supported the efficacy of motivational enhancement therapy and cognitive and behavioral therapy interventions with adjunction of contingency management for abstinence when possible. There was no relevant mention of craving in the 2006 review and very few in the 2016 review.

CONCLUSION

The methods and results of the last two Cochrane reviews on psychosocial interventions for cannabis use disorder were mostly similar. Consistent with other reviews on the same subject and reviews of psychotherapies for other substance use disorders, the 2016 review confirmed evidence already available in the 2006 review. Instead of confirming already confirmed evidence, future research is needed to determine if craving focused treatment would increase efficiency and how to maintain initial treatment outcomes long-term.

The Cannabinoid Delta-9-tetrahydrocannabinol Disrupts Estrogen Signaling in Human Placenta

Cannabis consumption is increasing worldwide either for recreational or medical purposes. Its use during gestation is associated with negative pregnancy outcomes such as, intrauterine growth restriction, preterm birth, low birth weight, and increased risk of miscarriage, though the underlying molecular mechanisms are unknown. Cannabis sativa main psychoactive compound, Δ9-tetrahydrocannabinol (THC) is highly lipophilic, and as such, readily crosses the placenta. Consequently, THC may alter normal placental development and function. Here, we hypothesize alterations of placental steroidogenesis caused by THC exposure. The impact on placental estrogenic signaling was examined by studying THC effects upon the enzyme involved in estrogens production, aromatase and on estrogen receptor α (ERα), using placental explants, and the cytotrophoblast cell model BeWo. Aromatase expression was upregulated by THC, being this effect potentiated by estradiol. THC also increased ERα expression. Actions on aromatase were ERα-mediated, as were abolished by the selective ER downregulator ICI-182780 and dependent on the cannabinoid receptor CB1 activation. Furthermore, the presence of the aromatase inhibitor Exemestane did not affect THC-induced increase in ERα expression. However, THC effects on ERα levels were reversed by the antagonists of CB1 and CB2 receptors AM281 and AM630, respectively. Thus, we demonstrate major alterations in estrogen signaling caused by THC, providing new insight on how cannabis consumption leads to negative pregnancy outcomes, likely through placental endocrine alterations. Data presented in this study, together with our recently reported evidence on THC disruption of placental endocannabinoid homeostasis, represent a step forward into a deeper comprehension of the puzzling actions of THC.

Risk Assessment of Over-the-Counter Cannabinoid-Based Cosmetics: Legal and Regulatory Issues Governing the Safety of Cannabinoid-Based Cosmetics in the UAE

Purpose: The lack of scientific evidence of the safety and efficacy of over-the-counter topical cannabinoid-based cosmetics remains a concern. The current study attempted to assess the quality of cannabinoid-based cosmetic products available on the UAE market. In particular, the study attempted to quantify the presence of undeclared tetrahydrocannabinol, specifically delta-9-tetrahydrocannabinol (THC) and delta-9-tetrahydrocannabinolic acid (THCA), in these products. Methods: A total of 18 cannabinoid-based cosmetics were collected and analysed in this study. GC-MS analysis was used to determine the presence of total undeclared tetrahydrocannabinol. Results: The estimate for the average tetrahydrocannabinol content was 0.011% with a 95% CI (0.004−0.019). Leave-on cosmetics products are more likely to contain total tetrahydrocannabinol compared to rinse-off cosmetics (p = 0.041). Although there was no statistically significant difference in the total tetrahydrocannabinol according to cosmetic category, there was a tendency towards higher tetrahydrocannabinol content in the hand care products, baby products, and body care preparations. Conclusion: The current study reveals the need for producers of cannabinoid-based cosmetic products to issue quality certificates for each batch produced to inform users of the tested levels of tetrahydrocannabinol.

Use of alcohol, tobacco, cannabis, and other substances during the first wave of the SARS-CoV-2 pandemic in Europe: a survey on 36,000 European substance users

BACKGROUND

SARS-CoV-2 reached Europe in early 2020 and disrupted the private and public life of its citizens, with potential implications for substance use. The objective of this study was to describe possible changes in substance use in the first months of the SARS-CoV-2 pandemic in Europe.

METHODS

Data were obtained from a cross-sectional online survey of 36,538 adult substance users from 21 European countries conducted between April 24 and July 22 of 2020. Self-perceived changes in substance use were measured by asking respondents whether their use had decreased (slightly or substantially), increased (slightly or substantially), or not changed during the past month. The survey covered alcohol (frequency, quantity, and heavy episodic drinking occasions), tobacco, cannabis, and other illicit drug use. Sample weighted data were descriptively analysed and compared across substances.

RESULTS

Across all countries, use of all substances remained unchanged for around half of the respondents, while the remainder reported either a decrease or increase in their substance use. For alcohol use, overall, a larger proportion of respondents indicated a decrease than those reporting an increase. In contrast, more respondents reported increases in their tobacco and cannabis use during the previous month compared to those reporting decreased use. No distinct direction of change was reported for other substance use.

CONCLUSIONS

Our findings suggest changes in use of alcohol, tobacco and cannabis during the initial months of the pandemic in several European countries. This study offers initial insights into changes in substance use. Other data sources, such as sales statistics, should be used to corroborate these preliminary findings.

Rapid Distinction and Semiquantitative Analysis of THC and CBD by Silver-Impregnated Paper Spray Mass Spectrometry

The control over the amount of psychoactive THC (Δ-9-tetrahydrocannabinol) in commercial cannabidiol (CBD) products has to be strict. A fast and simple semiquantitative Ag(I)-impregnated paper spray mass spectrometric method for differentiating between THC and CBD, which show no difference in standard single-stage or tandem MS, was established. Because of a different binding affinity to Ag(I) ions, quasi-molecular Ag(I) adducts [THC + Ag]+ and [CBD + Ag]+ at m/z 421 and 423 give different fragmentation patterns. The product ions at m/z 313 for THC and m/z 353 and 355 for CBD can be used to distinguish THC and CBD and to determine their ratio. Quantification of THC/CBD ratios in commercial CBD oils was accomplished with a low matrix effect (-2.2 ± 0.4% for THC and -2.0 ± 0.3% for CBD). After simple methanol extraction (recovery of 87.3 ± 1.2% for THC and 92.3 ± 1.4% for CBD), Ag(I)-impregnated paper spray analysis was employed to determine this ratio. A single run can be completed in a few minutes. This method was benchmarked against the UHPLC-UV method. Ag(I)-impregnated paper spray MS had the same working range (THC/CBD = 0.001-1) as UHPLC-UV analysis (R2 = 0.9896 and R2 = 0.9998, respectively), as well as comparable accuracy (-2.7 to 14%) and precision (RSD 1.7-11%). The method was further validated by the analysis of 10 commercial oils by Ag(I)-impregnated paper spray MS and UHPLC-UV analysis. Based on the determined relative concentration ratios of THC/CBD and the declared CBD concentration, 6 out of 10 CBD oils appear to contain more THC than the Dutch legal limit of 0.05%.

Cannabis use among Norwegian university students: Gender differences, legalization support and use intentions, risk perceptions, and use disorder

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Past year cannabis use was fairly common in a sample of Norwegian college students.

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About 6% of users possibly met criteria for use disorder, function of use frequency.

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Legalization attitudes and risk perceptions were associated with cannabis use risk.

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Intentions to use cannabis if legal were evident even among some current non-users.

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Many non-users expressed uncertainty in legalization attitudes and risk perceptions.

Aims

We explored past-year cannabis use and associated characteristics, focusing on legalization attitudes, use intentions, risk perceptions, and possible dependence among Norwegian university/college students.

Methods

We examined a nation-wide sample of Norwegian university/college students (N = 49,688; 67% female) who participated in the Students’ Health and Wellbeing Study (SHoT-study) in 2018. Participants reported past-year substance use, support for cannabis legalization, intent to use cannabis if legal, and perceived risks of weekly use. Past-year cannabis use (including use frequency) was examined in relation to these indicators. Legalization support, use intentions, and risk perceptions were examined in relation to use and gender. Potential cannabis use disorder was assessed with the Cannabis Abuse Screening Test (CAST) and examined in relation to use frequency and gender.

Findings

Past-year use was reported by 15.3% (11.8% women; 22.9% men). Majority of current users (roughly 90%) used no more than 50 times past year, and 6% (3.8% women; 8.5% men) met CAST use disorder criteria. Legalization support, use intentions, and no/low risk perceptions were significantly associated with greater odds of use, and greater use frequency among current users in both crude and adjusted models. Legalization support (23.0%), use intentions (14.0%), and perceptions of no/low risk (29.2%) were also relatively common even among current non-users, especially men. Male gender and more frequent use were associated with greater CAST scores and greater odds of use disorder.

Conclusions

Cannabis use was relatively common in this student sample. In addition to targeting frequent use, interventions may focus on cannabis-related attitudes and risk perceptions among uncertain/uninformed students.

Cannabis: An Emerging Occupational Allergen?

Cannabis is the most commonly used psychoactive drug. In recent years, Cannabis access has expanded for both medicinal and non-medicinal has grown. This is also marked with an increasing number of individuals gaining employment in this emerging industry. In this article, we briefly discuss the health hazards associated with Cannabis exposure with an emphasis on the potential for allergic reactions in workers who handle and process Cannabis plant.

Early, Chronic, and Acute Cannabis Exposure and Their Relationship With Cognitive and Behavioral Harms

Background: Cannabis is the third most consumed drug worldwide. Thus, healthcare providers should be able to identify users who are in need for an intervention. This study aims to explore the relationship of acute, chronic, and early exposure (AE, CE, and EE) to cannabis with cognitive and behavioral harms (CBH), as a first step toward defining risky cannabis use criteria. Methods: Adults living in Spain who used cannabis at least once during the last year answered an online survey about cannabis use and health-related harms. Cannabis use was assessed in five dimensions: quantity on use days during the last 30 days (AE), frequency of use in the last month (AE), years of regular use (YRCU) (CE), age of first use (AOf) (EE), and age of onset of regular use (AOr) (EE). CBH indicators included validated instruments and custom-made items. Pearson correlations were calculated for continuous variables, and Student's t-tests for independent samples were calculated for categorical variables. Effect sizes were calculated for each of the five dimensions of use (Cohen's d or r Pearson correlation) and harm outcome. Classification and Regression Trees (CART) analyses were performed for those dependent variables (harms) significantly associated with at least two dimensions of cannabis use patterns. Lastly, logistic binary analyses were conducted for each harm outcome. Results: The mean age of participants was 26.2 years old [standard deviation (SD) 8.5]. Out of 2,124 respondents, 1,606 (75.6%) reported at least one harm outcome (mean 1.8 and SD 1.5). In our sample, using cannabis on 3 out of 4 days was associated with an 8-fold probability of scoring 4+ on the Severity Dependence Scale (OR 8.33, 95% CI 4.91-14.16, p <0.001), which is indicative of a cannabis use disorder. Also, a start of regular cannabis use before the age of 25 combined with using cannabis at least once per month was associated with a higher probability of risky alcohol use (OR 1.33, 95% CI 1.12-1.57, p = 0.001). Besides, a start of regular cannabis use before the age of 18 combined with a period of regular use of at least 7.5 years was associated with a higher probability of reporting a motor vehicle accident (OR 1.81, 95% CI 1.41-2.32, p < 0.0001). Results were ambiguous regarding the role that age of first use and milligrams of THC per day of use might play regarding cannabis-related harms. Conclusions: The relationship among AE, CE, and EE with CBH indicators is a complex phenomenon that deserves further studies. The pattern of cannabis use should be carefully and widely evaluated-(not just including frequency but also other dimensions of pattern of use)-in research (preferably in longitudinal studies) to assess cannabis-related harms.

Determination of cannabinoids in urine, oral fluid and hair samples after repeated intake of CBD-rich cannabis by smoking

Cannabidiol prevalent (CBD-rich) cannabis derivatives are increasingly popular and widely available on the market as replacement of THC, tobacco substitutes or therapeutics for various health conditions. In this paper, we evaluate the impact of a repeated CBD-rich cannabis intake on levels of cannabinoids in biological samples. Urine, oral fluid and hair (pubic and head) samples were obtained from a naive user during a 26-day smoking period of one 250-mg CBD-rich cannabis joint/day containing 6.0% cannabidiol (CBD; 15mg) and 0.2% delta-9-tetrahydrocannabinol (THC; 0.5mg). In total, 35 urine, 8 oral fluid and 4hair sample were collected. Cannabinoids concentrations were quantified by a UHPLC/MSⁿ technique. The results suggested that the repeated exposure to CBD-rich cannabis (containing small amounts of THC) can generate positive results in biological samples. Urinary concentrations of 11-nor-9-carboxy-delta-9-tetrahydrocannabinol (THC-COOH) were quantitatively detected after 8 days from the smoking start and exceeded the 15ng/mL cut-off limit on day-15 even in the urine sample collected 12h after the last intake. In the oral fluid collected on day-26, no cannabinoids were found before the cannabis intake, thus excluding accumulation, while THC was detectable up to 3h after the cannabis intake, at concentrations progressively decreasing from about 18 to 6ng/mL. Hair samples collected one week after the end of the study turned out negative for THC and THC-COOH, suggesting that this matrix is suitable to discriminate the chronic consumption of CBD-rich cannabis from THC-prevalent products. The obtained findings are relevant for the interpretations of cannabinoids levels in biological fluids, also in light of the legal implications of a positive result.

Controlled administration of cannabis to mitigate cannabis-attributable harm among recreational users: a quasi-experimental study in Germany

Background: New approaches are required to slow down or reverse increasing trends of levels of delta-9-tetrahydrocannabinol (THC) and cannabis-attributable hospitalizations in Germany. Legal access to cannabis may constitute one viable effective policy response; however, available evidence does not suffice to inform a regulation model for Germany. The proposed study aims to reduce harm for cannabis users through legal access to herbal cannabis through pharmacies.

Protocol: A quasi-experimental study comparing cannabis users with legal access to herbal cannabis (Berlin, intervention group) to those without legal access (Hamburg, control group) (total N=698). As the primary outcome, we hypothesize that: 1) illegal THC consumption will reduce by at least 50% in the intervention group and 2) total THC exposure in the intervention group will be reduced by at least 10% lower than that of the control group, taking into account baseline values. Secondary outcomes comprise measures of frequency of use, THC-impaired driving, and mode of administration. Paired t-tests and multilevel regression models will be performed for statistical analyses.

Discussion: This study proposal is currently being reviewed by the ‘Federal Institute for Drugs and Medical Devices’ – the body responsible for approving research studies on classified substances, including cannabis. Upon approval and prior to the start of the study, a full ethical review will be undertaken. Results may inform a regulation model for Germany and other jurisdictions and are expected to deepen the understanding of the effects of legal access to cannabis.

Pre-registration: German Clinical Trials Register (DRKS), DRKS00020829

Topical Administration of Cannabidiol: Influence of Vehicle-Related Aspects on Skin Permeation Process

Cannabidiol (CBD) is a non-psychoactive cannabinoid isolated from Cannabis sativa which, given its claimed beneficial properties and therapeutic potential, has lately aroused considerable attention from the scientific community. Starting from the little literature evidence, the main purpose of this study was to investigate the topical administration of CBD, with particular focus on the influence of vehicle-related aspects on the skin permeation process. This could provide useful information for the design of suitable drug delivery systems which could be used in developing topical medicines and cosmetics. In vitro human skin permeation studies were conducted using modified Franz diffusion cells to compare the performance of four solutions and two semisolid formulations. The Hildebrand solubility parameter was used to better understand the thermodynamic aspects implied in the partitioning process of the cannabinoid compound into the skin. It was interestingly found that a hydrophilic gel, mostly consisting of propylene glycol (79%, w/w), can be an optimal choice for the topical administration of CBD. Moreover, the feasibility of the preparation of CBD-loaded (trans)dermal patches, made with new printing technology, was also demonstrated.

Emerging challenges in the extraction, analysis and bioanalysis of cannabidiol and related compounds

Cannabidiol (CBD) is a bioactive terpenophenolic compound isolated from Cannabis sativa L. It is known to possess several properties of pharmaceutical interest, such as antioxidant, anti-inflammatory, anti-microbial, neuroprotective and anti-convulsant, being it active as a multi-target compound. From a therapeutic point of view, CBD is most commonly used for seizure disorder in children. CBD is present in both medical and fiber-type C. sativa plants, but, unlike Δ⁹-tetrahydrocannabinol (THC), it is a non-psychoactive compound. Non-psychoactive or fiber-type C. sativa (also known as hemp) differs from the medical one, since it contains only low levels of THC and high levels of CBD and related non-psychoactive cannabinoids. In addition to medical Cannabis, which is used for many different therapeutic purposes, a great expansion of the market of hemp plant material and related products has been observed in recent years, due to its usage in many fields, including food, cosmetics and electronic cigarettes liquids (commonly known as e-liquids). In this view, this work is focused on recent advances on sample preparation strategies and analytical methods for the chemical analysis of CBD and related compounds in both C. sativa plant material, its derived products and biological samples. Since sample preparation is considered to be a crucial step in the development of reliable analytical methods for the determination of natural compounds in complex matrices, different extraction methods are discussed. As regards the analysis of CBD and related compounds, the application of both separation and non-separation methods is discussed in detail. The advantages, disadvantages and applicability of the different methodologies currently available are evaluated. The scientific interest in the development of portable devices for the reliable analysis of CBD in vegetable and biological samples is also highlighted.

Impact of tetrahydrocannabinol on the endocannabinoid 2-arachidonoylglycerol metabolism: ABHD6 and ABHD12 as novel players in human placenta

Cannabis use has been increasing worldwide for recreational and medical purposes. Consumption by pregnant women is associated with disturbances in pregnancy outcome, such as low birth weight, prematurity and intrauterine growth retardation, though the underlying biochemical mechanisms are unknown. The endocannabinoid system is involved in several reproductive events and the disruption of its homeostasis by ∆⁹-tetrahydrocannabinol (THC), the main psychoactive cannabinoid, may lead to a negative gestational outcome. In human placenta, THC impairs the levels of the endocannabinoid anandamide (AEA). The other major endocannabinoid, 2-arachidonoylglycerol (2-AG) also plays an important role on proper placentation and pregnancy success. However, THC impact on 2-AG homeostasis has never been addressed. Hence, the effects of THC in 2-AG levels and metabolic enzymes expression were explored. Long-term treatment impairs the expression of the main 2-AG synthetic and degradative enzymes. Curiously, with the highest concentration, despite the maintenance of diacylglycerol lipase alpha (DAGLα) and the decrease in monoacylglycerol lipase (MAGL) expression, 2-AG levels remain constant. Given the endocannabinoid signalling local tight regulation, we hypothesize the involvement of other 2-AG degradative enzymes. Indeed, THC increases the expression of the hydrolyzing enzymes alpha beta hydrolase domain-6 (ABHD6) and -12 (ABHD12), that we firstly describe in human placental tissues. The results show that THC, depending on time of exposure, induces alterations in 2-AG metabolic enzymes expression in placental explants, highlighting the importance of 2-AG regulation and endocannabinoid signalling in placental development. Alterations in this homeostasis may explain the negative pregnancy outcome related to cannabis consumption.

Neurobiological mechanisms underlying cannabis-induced memory impairment

A growing body of literature suggests that cannabis intake can induce memory loss in humans and animals. Besides the recreational use, daily cannabis users may also belong to the ever-increasing population of patients who are administered cannabis as a medicine. As such, they also can experience impairments in memory as a negative side effect of their therapy. Comprehension of the neurobiological mechanisms responsible for such detrimental effects would be therefore of paramount relevance to public health. The investigation of neurobiological mechanisms in humans, despite the progress in the development of imaging technologies that allow the study of brain structure and function, still suffers substantial limitations. Animal models, instead, enable us to establish a causal relationship and thus to better elucidate the neurobiological mechanisms underlying the process under study. In this review, we will attempt to collect the insight coming from animal models about cannabis effects on memory, trying to depict a picture of the neurobiological mechanisms contributing to the development of cognitive deficits following cannabis use.

Considerations and Implications of Cannabidiol Use During Pregnancy

PURPOSE OF REVIEW

Cannabis is a naturally occurring plant that is composed of over sixty phytocannabinoids, of which cannabidiol (CBD) has been recently identified as having therapeutic potential.

RECENT FINDINGS

Although not clearly understood in its mechanism of action, CBD contains potent anti-inflammatory, anti-hyperalgesia, and analgesic qualities now being further analyzed for its use in the treatment of a plethora of diseases. Related to its large safety profile and lack of psychoactive effects typically associated with cannabis and tetrahydrocannabinol (THC), CBD is being used more frequently for self-treatment of chronic pain, anxiety, and depression. With the help of broad marketing, CBD is being used by numerous people, including pregnant women who use CBD as an anti-emetic. Since marijuana is legalized in many states in the USA, the use of CBD has increased not only in the general population but also in specific groups such as pregnant women with chronic pain. Despite CBD's accessibility, there are limited studies showing its safety during pregnancy. While the use of cannabis has been well explored in terms of the effects on pregnancy, the use of CBD during pregnancy thus far has limited literature. The goal of this investigation is to impart the current understanding of CBD and its effects of pregnancy.

The role of cannabis in treating anxiety: an update

PURPOSE OF REVIEW

Cannabis use for medical purposes has become increasingly common, including as treatment for mental health disorders such as anxiety. Unfortunately, the evidence examining its use in mental health has been slow to evolve, but is emerging. Given the widespread use of cannabis, it is important for both clinicians and those who suffer with anxiety to understand the effects of cannabis on symptoms of anxiety. In this review, we present recent, available evidence from animal models, clinical trials, and survey studies and evaluate the contribution of these studies to the current understanding of the role of cannabis in treating anxiety.

RECENT FINDINGS

In reviewing recent evidence, we observed significant inconsistencies across findings from preclinical studies. Large-scale surveys suggest that cannabis may be effective in reducing anxiety, however, these results stand in contrast to equivocal findings from clinical trials.

SUMMARY

The literature evaluating the efficacy of cannabis in anxiety disorders is in its infancy. The survey data is generally positive. Although, while some animal studies posit cannabis constituents to have anxiolytic effects, others suggest the opposite or null results. Few new clinical trials have been conducted recently, and the extant trials have significant flaws in methodology. Although anecdotal evidence from survey studies, and a small signal found in animal studies and single-dose clinical trials provide early support that cannabis may be effective for alleviating anxiety, ultimately, the current evidence is equivocal. More high-quality clinical trials must be published before sound conclusions regarding the efficacy of cannabis for treating anxiety can be drawn.

A Warning against the Negligent Use of Cannabidiol in Professional and Amateur Athletes

Cannabidiol (CBD) is a non-psychoactive cannabinoid, widely marketed to athletes for claimed effects such as decreased anxiety, fear memory extinction, anti-inflammatory properties, relief of pain and for post-exercise recovery. The World Anti-Doping Agency (WADA) has excluded CBD from its list of prohibited substances. Nevertheless, caution is currently advised for athletes intending to use the compound-except CBD, all other cannabinoids are still on the prohibited list. CBD products, specifically non-medicinal, so-called full-spectrum cannabis extracts, may contain significant levels of these substances, but also contaminations of tetrahydrocannabinol (THC) (>2.5 mg/day in >30% of products on the German market) potentially leading to positive doping tests. Labelled claims about CBD content and absence of THC are often false and misleading. Contaminations with the psychoactive THC can result in adverse effects on cognition and, in general, the safety profile of CBD with respect to its toxicity is a controversial topic of discussion. For these reasons, we would currently advise against the use of over-the-counter CBD products, especially those from dubious internet sources without quality control.

[Cannabis-derived medicines for the treatment of chronic pain : Problems resulting from medical appraisals in the experience of the Medical Advisory Board of the Statutory Health Insurance Funds North]

BACKGROUND

On March 10th 2017, the law amending narcotic and other regulations was expanded, thereby allowing physicians, irrespective of their specialization, to prescribe cannabis-derived medicines as magistral formulas or proprietary medicinal products at the expense of the German statutory health insurance (GKV). First prescription requires approval from the respective health insurance, which in turn commissions the Medical Advisory Board of the Statutory Health Insurance Funds (MDK) to prepare a medico-legal report.

OBJECTIVES

Since § 31 Para. 6 of the German Social Code, Book V (SGB V) came into effect, a multitude of imponderables have been reported regarding reimbursement. Based on the experience of the MDK Nord, problems within the fields of patients, physicians and cannabis-derived medicines are illustrated.

MATERIAL AND METHODS

Considering current literature, a retrospective review was conducted including approximately 2200 applications for reimbursement received in 2018 from patients residing in Hamburg and Schleswig-Holstein.

RESULTS

A relevant problem within the field of patients resulted from the lack of a specific definition of the term "severe (chronic) disease". Although this term is mentioned several times in SGB V, it is not put into concrete terms. Circumstances like multimorbidity are not taken into account. Another problem consisted in an irreproducible anticipation of treatment with cannabis-derived medicines. Within the field of physicians, a major problem was caused by missing, fragmentary or inconsistent information regarding disease and/or therapy. Hence, initially, almost one-third of all applications could not be appraised. Amongst various cannabis-derived medicines, dried flowers were found to be the most problematic regarding doses and effective levels. Notably, a marked increase in numbers of applications for reimbursement of therapy with pure cannabidiol was noted.

DISCUSSION

Numerous problems reported elsewhere and relating to prescription of cannabis-derived medicines were also observed by the MDK Nord. Many prescriptions reflected an uncertainty regarding therapeutic use of cannabis-derived medicines. Thus, one should consider restricting the prescription of cannabis-derived medicines to selected specialists. It should be noted that, in individual cases, e.g., patients suffering from neuropathic pain, treatment with cannabis-derived medicines seems to be a reasonable therapeutic option taking into account the risks and benefits.

Time Trends in the Co-use of Cannabis and the Misuse of Tranquilizers, Sedatives and Sleeping Pills among Young Adults in Spain between 2009 and 2015

The aims of this study were: (a) to estimate time trends in the prevalence of the co-use of cannabis and other cannabis-based products (CBP) with the misuse of tranquilizers, sedatives, and sleeping pills (TSSp) between 2009 and 2015; and (b) to identify the factors associated with the probability of the co-use of CBP with TSSp misuse during this period among Spanish younger adults (15–34 years old). We analyzed data collected from the Spanish National Surveys on Alcohol and Other Drugs (EDADES) in 2009, 2011, 2013, and 2015. CBP co-use with TSSp misuse were the dependent variables. We also analyzed sociodemographic features, self-perceived health status, lifestyle habits, perceived health risk of consumption, and perceived availability of substance using logistic regression models. The prevalence of CBP co-use with TSSp misuse has decreased in Spain. The factors associated with co-use were a lack of education (OR 2.34), alcohol (OR 7.2), tobacco (OR 6.3) and other illicit psychoactive drug (OR 6.5) consumption, perceived non-health risk for the consumption of CBP and TSSp (OR 3.27), and perceived availability of CBP (OR 2.96). Our study identified several factors that appear to affect CBP and TSSp co-use in younger adults, with potential implications for healthcare providers.

Are adverse effects of cannabidiol (CBD) products caused by tetrahydrocannabinol (THC) contamination?

Cannabidiol (CBD)-containing products are widely marketed as over the counter products, mostly as food supplements. Adverse effects reported in anecdotal consumer reports or during clinical studies were first assumed to be due to hydrolytic conversion of CBD to psychotropic Δ ⁹-tetrahydrocannabinol (Δ ⁹-THC) in the stomach after oral consumption. However, research of pure CBD solutions stored in simulated gastric juice or subjected to various storage conditions such as heat and light with specific liquid chromatographic/tandem mass spectrometric (LC/MS/MS) and ultra-high pressure liquid chromatographic/quadrupole time-of-flight mass spectrometric (UPLC-QTOF) analyses was unable to confirm THC formation. Another hypothesis for the  adverse effects of CBD products may be residual Δ ⁹-THC concentrations in the products as contamination, because most of them are based on hemp extracts containing the full spectrum of cannabinoids besides CBD. Analyses of 181 food products of the German market (mostly CBD oils) confirmed this hypothesis: 21 products (12%) contained Δ ⁹-THC above the lowest observed adverse effect level (2.5 mg/day). Inversely, CBD was present in the products below the no observed adverse effect level. Hence, it may be assumed that the adverse effects of some commercial CBD products are based on a low-dose effect of Δ ⁹-THC and not due to effects of CBD itself. The safety, efficacy and purity of commercial CBD products is highly questionable, and all of the products in our sample collection showed various non-conformities to European food law such as unsafe Δ ⁹-THC levels, hemp extracts or CBD isolates as non-approved novel food ingredients, non-approved health claims, and deficits in mandatory food labelling requirements. In view of the growing market for such lifestyle products, the effectiveness of the instrument of food business operators' own responsibility for product safety and regulatory compliance must obviously be challenged, and a strong regulatory framework for hemp products needs to be devised.

Are adverse effects of cannabidiol (CBD) products caused by tetrahydrocannabinol (THC) contamination?

Cannabidiol (CBD)-containing products are widely marketed as over the counter products, mostly as food supplements. Adverse effects reported in anecdotal consumer reports or during clinical studies were first assumed to be due to hydrolytic conversion of CBD to psychotropic Δ 9-tetrahydrocannabinol (Δ 9-THC) in the stomach after oral consumption. However, research of pure CBD solutions stored in simulated gastric juice or subjected to various storage conditions such as heat and light with specific liquid chromatographic/tandem mass spectrometric (LC/MS/MS) and ultra-high pressure liquid chromatographic/quadrupole time-of-flight mass spectrometric (UPLC-QTOF) analyses was unable to confirm THC formation. Another hypothesis for the adverse effects of CBD products may be residual Δ 9-THC concentrations in the products as contamination, because most of them are based on hemp extracts containing the full spectrum of cannabinoids besides CBD. Analyses of 293 food products of the German market (mostly CBD oils) confirmed this hypothesis: 28 products (10%) contained Δ 9-THC above the lowest observed adverse effect level (2.5 mg/day). Hence, it may be assumed that the adverse effects of some commercial CBD products are based on a low-dose effect of Δ 9-THC, with the safety of CBD itself currently being unclear with significant uncertainties regarding possible liver and reproductive toxicity. The safety, efficacy and purity of commercial CBD products is highly questionable, and all of the products in our sample collection showed various non-conformities to European food law such as unsafe Δ 9-THC levels, hemp extracts or CBD isolates as non-approved novel food ingredients, non-approved health claims, and deficits in mandatory food labelling requirements. In view of the growing market for such lifestyle products, the effectiveness of the instrument of food business operators' own responsibility for product safety and regulatory compliance must obviously be challenged, and a strong regulatory framework for hemp products needs to be devised.