Medical cannabis use in Canada: vapourization and modes of delivery

Medicinal Use of Different Cannabis Strains: Results from a Large Prospective Survey in Germany

BACKGROUND

Up to now, it is unclear whether different medicinal cannabis (MC) strains are differently efficacious across different medical conditions. In this study, the effectiveness of different MC strains was compared depending on the disease to be treated.

METHODS

This was an online survey conducted in Germany between June 2020 and August 2020. Patients were allowed to participate only if they received a cannabis-based treatment from pharmacies in the form of cannabis flowers prescribed by a physician.

RESULTS

The survey was completed by n=1,028 participants. Most participants (58%) have used MC for more than 1 year, on average, 5.9 different strains. Bedrocan (pure tetrahydrocannabinol to pure cannabidiol [THC:CBD]=22:<1) was the most frequently prescribed strain, followed by Bakerstreet (THC:CBD=19:<1) and Pedanios 22/1 (THC:CBD=22:1). The most frequent conditions MC was prescribed for were different pain disorders, psychiatric and neurological diseases, and gastrointestinal symptoms. Overall, the mean patient-reported effectiveness was 80.1% (range, 0-100%). A regression model revealed no association between the patient-reported effectiveness and the variety. Furthermore, no influence of the disease on the choice of the MC strain was detected. On average, 2.1 side effects were reported (most commonly dry mouth (19.5%), increased appetite (17.1%), and tiredness (13.0%)). However, 29% of participants did not report any side effects. Only 398 participants (38.7%) indicated that costs for MC were covered by their health insurance.

CONCLUSIONS

Patients self-reported very good efficacy and tolerability of MC. There was no evidence suggesting that specific MC strains are superior depending on the disease to be treated.

Where Do Adults in the United States Obtain Cannabis? A Nationally Representative Study Examining the Relationships Between Sociodemographic Factors, Cannabis Use Characteristics and Sources of Cannabis

OBJECTIVE

Characterization of population subgroups based on where they acquire cannabis is unexplored. We examine relationships between sociodemographic characteristics, cannabis use modality, risky cannabis use, and source of cannabis.

METHOD

Analyzing a representative sample (unweighted n = 8,089) of U.S. adults living in medical cannabis-permitting states with past-year cannabis use from the 2021 National Survey on Drug Use and Health, we determined source of last cannabis used. Outcome groups were purchased from a dispensary, purchased from another source, or nonpurchased source. Incorporating the complex survey design, descriptive statistics and adjusted multinomial logistic regressions evaluated associations between sociodemographic, individual cannabis use characteristics, and source of cannabis. Secondary analyses described cannabis purchasing characteristics among the subsample who last purchased cannabis.

RESULTS

Purchasing from a dispensary was the most common source of cannabis (42.5%). Significant relationships between sociodemographic characteristics, cannabis use modality, risky cannabis use, and source of cannabis were found. Recent cannabis initiates and those with cannabis vaporizer use had an increased likelihood of purchasing cannabis from a dispensary. Purchasing from a nondispensary source was most likely among those with daily cannabis use, past-month blunt use, past-year driving under the influence, cannabis use disorder, and cannabis and alcohol co-use. Among those purchasing cannabis, joints and other forms of cannabis were more likely to be purchased from a dispensary than purchased from other sources.

CONCLUSIONS

We identified key sociodemographic and cannabis use characteristics that may influence where individuals obtain cannabis, which are important for cannabis behavior surveillance and cannabis use prevention and intervention strategies to consider.

Cardiovascular and Respiratory Effects of Cannabis Use by Route of Administration: A Systematic Review

Aim: Knowledge of the cardiovascular and respiratory effects of cannabis use by route of administration is unclear. This evidence is necessary to increase clinical and public health awareness given the recent trend in cannabis legalization, normalization, and surge in the availability and usage of various forms of cannabis products. Methods: Search was conducted in Web of Science, ProQuest, Psych INFO, Scopus, Embase, and Medline databases, and subsequently in the references of retrieved articles. Peer-reviewed articles published between 2009 and 2023, that reported on cardiovascular and respiratory effects of cannabis use by route of administration were included. Studies with no report of the route of administration and combined use of other illicit substances were excluded. The review was guided by Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Results: Of the 1873 articles retrieved, 42 met inclusion criteria encompassing six case reports, 21 reviews, and 15 empirical studies. Four administration routes were identified: smoking, vaping, oral ingestion, and dabbing. Smoking was the most common route of administration and was associated with both respiratory effects, such as bronchitis, dyspnea, and chronic obstructive lung disease, and cardiovascular effects including tachycardia, ventricular arrhythmias, and myocardial infarction. Cannabis edibles were associated with minimal respiratory effects. Tachycardia was the most common cardiovascular effect and was associated with all routes of administration. Conclusion: Cannabis use does cause cardiovascular and respiratory effects, but the conclusion remains tentative of the cardiovascular and respiratory effects by route of administration due to methodological limitations of the studies.

Self-reported knowledge of tetrahydrocannabinol and cannabidiol concentration in cannabis products among cancer patients and survivors

PURPOSE

Cannabis use may introduce risks and/or benefits among people living with cancer, depending on product type, composition, and nature of its use. Patient knowledge of tetrahydrocannabinol (THC) or cannabidiol (CBD) concentration could provide information for providers about cannabis use during and after treatment that may aide in risk and benefit assessments. This study aimed to examine knowledge of THC or CBD concentration among patients living with cancer who consume cannabis, and factors associated with knowledge of cannabinoid concentrations.

METHODS

People living with cancer who consumed cannabis since their diagnosis (n = 343) completed an anonymous, mixed-mode survey. Questions assessed usual mode of delivery (MOD), knowledge of THC/CBD concentration, and how source of acquisition, current cannabis use, and source of instruction are associated with knowledge of THC/CBD concentration. Chi-square and separate binary logistic regression analyses were examined and weighted to reflect the Roswell Park patient population.

RESULTS

Less than 20% of people living with cancer had knowledge of THC and CBD concentration for the cannabis products they consumed across all MOD (smoking- combustible products, vaping- vaporized products (e-cigarettes), edibles-eating or drinking it, and oral- taking by mouth (pills)). Source of acquisition (smoking-AOR:4.6, p < 0.01, vaping-AOR:5.8, p < 0.00, edibles-AOR:2.6, p < 0.04), current cannabis use (edibles-AOR:5.4, p < 0.01, vaping-AOR: 11.2, p < 0.00, and oral-AOR:9.3, p < 0.00), and source of instruction (vaping only AOR:4.2, p < 0.05) were found to be variables associated with higher knowledge of THC concentration.

CONCLUSION

Self-reported knowledge of THC and CBD concentration statistically differed according to MOD, source of acquisition, source of instruction, and current cannabis use.

The Moderating Role of Health Status on the Association Between Depressive Symptoms and Cannabis Vaping

Objective

Cannabis vaping is increasing among college students. There is little information on risk factors for vaping cannabis. Consistent with the self-medication hypothesis, experiencing depressive symptoms and having a chronic medical condition (CMC) are associated with cannabis use among young adults. Individuals who experience both risk factors may be at higher risk for cannabis vaping. This study examined cross-sectional associations between depressive symptoms, CMC status, and cannabis vaping, and identified the moderating role of CMC status on depressive symptoms and cannabis vaping.

Method

College students (N = 3,742) self-reported on depressive symptoms, CMC status, and lifetime and current cannabis vaping (i.e., cannabis vaporizers; electronic nicotine devices to use cannabis). Data were collected Fall 2017 until Spring 2021. The sample was predominantly female (70.9%) and White (75.4%). Regression analyses were used.

Results

Greater depressive symptoms were related to increased likelihood of cannabis vaping across outcomes. Having a CMC was related to lifetime history of cannabis vaporizing. CMC status moderated the associations between depressive symptoms and lifetime cannabis vaporizing. Depressive symptoms were only a risk factor for cannabis vaporizing among college students without a CMC, not those with a CMC.

Conclusions

Interventions that teach adaptive ways of coping with depressive symptoms and the potential demands of managing a CMC in college are needed. Comprehensive programs for college students, with and without CMCs, are needed to support those with comorbid depression and cannabis vaping use.

A preliminary characterization of cannabis oil use and vaporization among individuals who use for medical purposes: A pilot study

Little is known about the naturalistic use of cannabis oil vaporization, a high-potency product with the ability to be administered discreetly. This pilot study evaluated the feasibility of utilizing a "smart" vaporizer and application to assess the timing, frequency, socioenvironmental factors, and substance use involved in cannabis oil vaporization. Adults with a medical cannabis registration card were recruited from a dispensary in Rhode Island and completed a 2-week study monitoring period using the Gram1 vaporizer, followed by a poststudy qualitative interview. The sample included nine adults who were predominantly male (89%), 100% White, and 100% non-Hispanic. The Gram1 collected topographical vaping data, and the cellphone application utilized ecological momentary assessment (EMA) to assess socioenvironmental factors and other substance use. Qualitative interview data were coded, and illustrative quotations were selected to support quantitative findings. A total of 224 vaping sessions were recorded reflecting 76.4% of the study monitoring period. There was an average of 1.79 vaping sessions per day across all days. Participants took 8.76 puffs on average (SD = 8.23) per vaping session, and the session lasted 2.59 min on average (SD = 4.19). Regular vaporization was exhibited across days of the week and hours of the day. EMA reports indicated that smoking cannabis flower was the most common additional mode of cannabis administration. This study utilized a naturalistic design with novel topographical data and EMA to characterize cannabis oil vaporization. These findings establish the feasibility of collecting objective, momentary data to better understand use behaviors which are critical to informing safe consumption. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Cannabinoids and the Endocannabinoid System in Early SARS-CoV-2 Infection and Long COVID-19-A Scoping Review

Coronavirus disease-19 (COVID-19) is a highly contagious illness caused by the SARS-CoV-2 virus. The clinical presentation of COVID-19 is variable, often including symptoms such as fever, cough, headache, fatigue, and an altered sense of smell and taste. Recently, post-acute "long" COVID-19 has emerged as a concern, with symptoms persisting beyond the acute infection. Vaccinations remain one of the most effective preventative methods against severe COVID-19 outcomes and the development of long-term COVID-19. However, individuals with underlying health conditions may not mount an adequate protective response to COVID-19 vaccines, increasing the likelihood of severe symptoms, hospitalization, and the development of long-term COVID-19 in high-risk populations. This review explores the potential therapeutic role of cannabinoids in limiting the susceptibility and severity of infection, both pre- and post-SARS-CoV-19 infection. Early in the SARS-CoV-19 infection, cannabinoids have been shown to prevent viral entry, mitigate oxidative stress, and alleviate the associated cytokine storm. Post-SARS-CoV-2 infection, cannabinoids have shown promise in treating symptoms associated with post-acute long COVID-19, including depression, anxiety, post-traumatic stress injury, insomnia, pain, and decreased appetite. While current research primarily focuses on potential treatments for the acute phase of COVID-19, there is a gap in research addressing therapeutics for the early and post-infectious phases. This review highlights the potential for future research to bridge this gap by investigating cannabinoids and the endocannabinoid system as a potential treatment strategy for both early and post-SARS-CoV-19 infection.

Exploring preferences for different modes of cannabis use during early pregnancy: A qualitative study

OBJECTIVE

Rates of prenatal cannabis use are rising, yet little is known about modes of cannabis use during pregnancy. This focus group study with pregnant individuals aimed to examine use patterns and perceptions regarding common modes of prenatal cannabis use.

METHOD

Kaiser Permanente Northern California pregnant adult patients who identified as White or Black and self-reported cannabis use during pregnancy were recruited to participate (N = 53; 40% Black, 60% White; Meanage = 30.3, SD = 5.2). Eighteen focus groups with race-concordant facilitators followed a semi-structured format that queried participants on their prenatal cannabis use, including preferred modes of use (e.g., vapes, blunts, dabs, joints, edibles, topicals, pipes). Focus group discussions were coded and analyzed using a general inductive approach.

RESULTS

A range of modes were preferred, with no single mode predominant. Participants' preferences aligned with four themes: perceived effects and benefits of cannabis, health and safety, convenience and familiarity, and partner and friend influences. Participants sought modes that were accessible and familiar, provided consistent and quick relief for pregnancy-related symptoms, were aligned with partners or friends, and minimized perceived risks while also providing symptom relief. Participants desired evidence-based information about mode safety to better inform mode selection during pregnancy.

CONCLUSIONS

A range of personal and social factors influenced mode preferences during pregnancy. Many participants desired to reduce harms and use cannabis more safely in pregnancy but received little mode-specific information to guide these preferences. Further research identifying mode-specific risks is needed to guide harm reduction approaches during pregnancy.

Use of flavored cannabis vaping products in the US, Canada, Australia, and New Zealand: findings from the international cannabis policy study wave 4 (2021)

Background: Vaping is an increasingly popular mode of cannabis use. Few studies have characterized the role of flavors in cannabis e-liquids.Objectives: To explore the prevalence of flavored vaping liquids, including differences between countries and correlates of use.Methods: Data were from Wave 4 (2021) of the International Cannabis Policy Study with national samples aged 16-65 in Canada, the United States (US), Australia, and New Zealand. The sample comprised 52,938 respondents, including 6,265 who vaped cannabis e-liquids in the past 12-months (2,858 females, 3,407 males). Logistic regression models examined differences in the use of flavored e-liquids between countries and sociodemographic characteristics.Results: The prevalence of vaping cannabis e-liquids was highest in the US (15.3%) and Canada (10.7%) compared to Australia (4.0%) and New Zealand (3.7%). Among past 12-month cannabis consumers, 57.5% reported using flavored vaping liquids, 34.2% used unflavored vaping products and 8.3% did not know. People who vape in Australia were most likely to report using flavored liquids compared to New Zealand (OR = 2.29), Canada (OR = 3.14), and the US (OR = 3.14) (p < .05 for all). Fruit was the most reported vaping flavor (40.8%), followed by candy/dessert (20.4%) and vanilla (15.2%). Use of flavored vapes was greater among younger, ethnic minorities, female, higher education and income adequacy, and more frequent consumers (p < .05).Conclusion: Many cannabis consumers reported using flavored e-liquids, with highest levels among young people aged 16-35. Given the high prevalence of vaping in legal markets, regulators should consider the role of flavored vaping products in promoting cannabis use among this group.

Vaporized cannabis extract-induced antinociception in male vs female rats with persistent inflammatory pain

ABSTRACT

Although preclinical studies generally report robust antinociceptive effects of cannabinoids in rodent persistent pain models, randomized controlled trials in chronic pain patients report limited pain relief from cannabis/cannabinoids. Differences between animal and human studies that may contribute to these discrepant findings include route of cannabis/cannabinoid administration, type of cannabis/cannabinoid, and how pain is measured. To address these factors, rats with complete Freund adjuvant (CFA)-induced hind paw inflammation were exposed acutely or repeatedly to vaporized cannabis extract that was either tetrahydrocannabinol (THC) or cannabidiol (CBD)dominant. One measure of evoked pain (mechanical threshold), 2 functional measures of pain (hind paw weight-bearing, and locomotor activity), and hind paw edema were assessed for up to 2 hours after vapor exposure. Acute exposure to vaporized THC-dominant extract (200 or 400 mg/mL) decreased mechanical allodynia and hind paw edema and increased hind paw weight-bearing and locomotor activity, with no sex differences. After repeated exposure to vaporized THC-dominant extract (twice daily for 3 days), only the antiallodynic effect was significant. Acute exposure to vaporized CBD-dominant cannabis extract (200 mg/mL) did not produce any effects in either sex; repeated exposure to this extract (100, 200, or 400 mg/mL) decreased mechanical allodynia in male rats only. Sex differences (or lack thereof) in the effects of vaporized cannabis extracts were not explained by sex differences in plasma levels of THC, CBD, or their major metabolites. These results suggest that although vaporized THC-dominant extract is likely to be modestly effective against inflammatory pain in both male and female rats, tolerance may develop, and the CBD-dominant extract may be effective only in male rats.

Exploring Consumer Preferences for Cannabis Vaping Products to Support Public Health Policy: A Discrete Choice Experiment

BACKGROUND

Phase two of cannabis legalisation in Canada brought cannabis vaping products to the market. This decision was controversial due to an outbreak of vaping cannabis use-associated lung injury. This resulted in three provinces banning the sale of cannabis vaping products causing inequitable access. This study sought to explore consumer preferences for cannabis vaping products to inform cannabis policy.

METHODS

We used a discrete choice experiment to explore consumer preferences for attributes of cannabis vaping products. Attributes included type of device, price, tetrahydrocannabinol (THC) potency, vape liquid content, product recommendations and Health Canada regulation. Participants lived in Canada, were aged ≥ 19 years, and had purchased a cannabis vape in the last 12 months. A multinomial logit (MNL) model was used for the base model, and latent class analysis to assess preference sub-groups.

RESULTS

In total, 384 participants completed the survey; the MNL model showed that price and potency were the most important attributes. A three-group latent class model showed that ~ 40% of the sample was driven primarily by Health Canada Regulation and were willing to pay $56 more for a product that was regulated compared to one that was not. About 33% of the sample was driven by price, and 26% was driven by type of device.

CONCLUSION

While regulated status by Health Canada was most important to some consumers (~ 40%), nearly 60% of the sample were willing to make trade-offs in regulated status for products with a lower price. Therefore, policymakers need to consider the broader public health implications of banning cannabis vapes in some regions.

Lessons from 20 years of medical cannabis use in Canada

BACKGROUND

Canada was one of the first countries to regulate the medical use of cannabis. However, literature on Canada's medical cannabis program is limited.

METHODS

We use administrative data from the medical cannabis program, and licensed cannabis vendor catalog data to describe a) the participation of patients, physicians, and cannabis vendors in the program from its inception in 1999 to 2021, and b) trends in medical cannabis consumption, prices and potency. We also use national surveys conducted over the last several decades to estimate trends in regular cannabis use (medical or otherwise) and how it changed during the medical cannabis access regimes.

RESULTS

In 2001, the Canadian government granted access to those with physician-documented evidence of a severe health problem that could not be managed using conventional therapies. Most patients accessed cannabis grown under a personal production license. By 2013, authorized daily cannabis dosages were very high. In 2014, the government, concerned over illegal diversion, required that cannabis be purchased from a licensed commercial grower; personal production was banned. Physicians were given responsibility for authorizing patient access. To fill the regulatory void, the physician regulatory bodies in Canada imposed their own prescribing restrictions. After these changes, the number of physicians who were willing to support patient cannabis use markedly decline but the number of patients participating in the program sharply increased. Medical cannabis use varied by province-rates were generally lower in provinces with stricter regulations on physician cannabis prescribing. Most varieties of cannabis oil available for sale are now high in CBD and low in THC. Dry cannabis varieties, conversely, tend to be high in THC and low in CBD. Inflation adjusted prices of most varieties of medical cannabis have declined over time. We find that rates of daily cannabis use (medical or otherwise) increased markedly after the 2014 policy regime. The fraction of Canadians using cannabis daily increased again after the 2018 legalization of recreational cannabis; at the same time, participation in the medical access program declined.

CONCLUSION

The implications for patient health outcomes of changes in the medical cannabis program and legalization of recreational use remains an important area for future research.

Risky cannabis use is associated with varying modes of cannabis consumption: Gender differences among Canadian high school students

BACKGROUND

Our objective was to explore associations between indicators of more risky cannabis use (i.e., solitary use, frequent use, and younger age of initiation) and different modes of cannabis use (i.e., smoking, vaping and/or edibles).

METHODS

Data were gathered from a large sample of Canadian youth in Alberta, British Columbia, Ontario, and Quebec who participated in Year 8 (2019-20) of the COMPASS study, and who reported using cannabis in the past year (n = 4,763). Generalized estimating equations were used to examine associations between risky cannabis use and modes of cannabis use, stratified by gender.

RESULTS

Overall, 38% of students reported using multiple modes of cannabis use. Consistent among both males and females, students who used cannabis alone (35%) and at a higher frequency (55%) were more likely to use multiple modes than smoking only. Among females, those who used cannabis alone were more likely to report using edibles only compared to smoking only (aOR=2.27, 95%CI=1.29-3.98). Earlier cannabis use initiation was associated with lower likelihood of vaping cannabis only among males (aOR=0.25; 95%CI = 0.12-0.51), and lower likelihood of using edibles only among females (aOR=0.35; 95%CI = 0.13-0.95), than by smoking only.

CONCLUSIONS

Our findings suggest that multiple modes of use may be an important indicator or risky cannabis use among youth, given associations with frequency, solitary use, and age of onset.

Differences between adults who smoke cigarettes daily and do and do not co-use cannabis: Findings from the 2020 ITC four country smoking and vaping survey

BACKGROUND

Little is known about population-level differences between adults who exclusively smoke cigarettes and those who smoke cigarettes and also use cannabis (co-consumers). Thus, this study describes differences on sociodemographic, cigarette-dependence, health and behavioral variables, and risk perceptions associated with smoking cannabis.

METHODS

This cross-sectional study included 6941 respondents from the 2020 ITC Four Country Smoking and Vaping Survey (US, Canada, Australia, England). Adult daily cigarette smokers were included and categorized as: cigarette-only smokers (never used cannabis/previously used cannabis, but not in the past 12 months, n = 4857); occasional co-consumers (cannabis use in the past 12 months, but < weekly use, n = 739); or regular co-consumers (use cannabis ≥ weekly, n = 1345). All outcomes were self-reported. Regression models were conducted on weighted data.

RESULTS

Overall, 19.9 % of respondents reported regular cannabis co-use and 10.1 % reported occasional co-use. Regular co-use was highest in Canada (27.2 %), followed by the US (24.4 %), England (12.7 %) and Australia (12.3 %). Compared to cigarette-only smokers, regular co-consumers were more likely to be male and report chest/breathing problems (p < 0.001). All co-consumers were more likely to be younger, have lower income, be experiencing financial stress, reside in Canada, have depressive symptoms, use alcohol more frequently and binge drink, use other tobacco/nicotine products, and perceive smoking cannabis as low health risk and less harmful than smoking cigarettes (all p < 0.001). Cigarette dependence measures were similar between co-consumers and cigarette-only smokers (all p ≥ 0.05).

CONCLUSIONS

Although there were no differences on cigarette dependence measures between daily cigarette smokers who do and do not use cannabis, there are several other risk factors that may affect tobacco use and abstinence among co-consumers (e.g., greater depression, high-risk alcohol consumption). Thus, tobacco cessation treatment may require multi-pronged strategies to address other health behaviors. Continued surveillance is needed to determine the nature and health implications of co-use considering changing policies, markets, and products.

Evidence That Metal Particles in Cannabis Vape Liquids Limit Measurement Reproducibility

Cannabis vaping involves the vaporization of a cannabis vaping liquid or solid via a vaping accessory such as a vape pen constructed of various metals or other parts. An increasing number of reports advocate for expansion of the testing and regulation of metal contaminants in cannabis vape liquids beyond the metals typically tested such as arsenic, cadmium, mercury, and lead to reflect the possibility of consumers' exposure to other metal contaminants. Metal contaminants may originate not only from the cannabis itself but also from the vape devices in which the cannabis vape liquid is packaged. However, metal analyses of cannabis vape liquids sampled from cannabis vaping devices are challenged by poor precision and reproducibility. Herein, we present data on the metal content of 12 metals in 20 legal and 21 illegal cannabis vape liquids. The lead mass fraction in several illegal samples reached up to 50 μg g^-1. High levels of nickel (max 677 μg g^-1) and zinc (max 426 μg g^-1) were found in illegal samples, whereas the highest copper content (485 μg g^-1) was measured in legal samples. Significant differences in metal mass fractions were observed in the legal cannabis vape liquid taken from two identical devices, even though the liquid was from the same lot of the same cannabis product. Metal particles in the vape liquids were observed by scanning electron microscopy, and laser ablation inductively coupled plasma mass spectrometry confirmed the presence of copper-, zinc-, lead-, and manganese-bearing particles, metals that are in common alloys that may be used to make vape devices. Colocalized particles containing aluminum, silica, and sodium were also detected. These results suggest that metal particles could be a contributing factor to poor measurement precision and for the first time, to the best of our knowledge, provide evidence of metal particles in cannabis vape liquids contained in unused cannabis vape pens.

Vaping preferences of individuals who vaporise dry herb cannabis, cannabis liquids and cannabis concentrates

In 2019 an estimated 200 million people aged 15-64 used cannabis, making cannabis the most prevalent illicit substance worldwide. The last decade has seen a significant expansion in the cannabis vaporiser market, introducing cannabis vaporisation as a common administration method alongside smoking and ingestion. Despite reports of increased prevalence of cannabis vaporisation there has been little research into the use of these devices. To remedy the current dearth of data in this area this study utilised an anonymous online survey of individuals who self-reported past cannabis vaporisation. The respondents (N = 557) were predominantly young (<35 years) and male. Most (91.4 %) stated they had ever vaped dry herb cannabis, 59.1 % reported vaporisation of cannabis oil or liquids, and 34.0 % reported vaporisation of cannabis concentrates. This study identifies the types of vaporisation devices (including brands and models) employed by cannabis vapers, as well as the vaporisation temperatures and puff durations commonly used for dry herb, cannabis liquids and cannabis concentrates. To the best of our knowledge, this is the first time the usual operating temperatures of these vaporisation devices and user specific consumption patterns such as puff duration have been reported for cannabis vaping. This information will allow for a more realistic understanding of patterns of recreational use and improve experimental conditions in research settings to reflect the user's context.

Tobacco/nicotine use among individuals using cannabis for therapeutic purposes

BACKGROUND AND OBJECTIVES

While the relationship between recreational cannabis and nicotine use is well established, little is known about nicotine use among users of cannabis for therapeutic purposes (CTP).

METHODS

Patients attending a medical marijuana dispensary (N = 697; 75.3% White; 60.0% male) completed a survey examining nicotine use, motivation to quit cigarette smoking, routes of administration of nicotine and cannabis, and CTP qualifying conditions.

RESULTS

More than one-third (39.3%) of participants reported current nicotine use. Compared to exclusive cigarette smokers, e-cigarette users and non-users of nicotine were approximately four times more likely to vape, rather than to smoke, cannabis. Furthermore, 46.8% of cigarette smokers reported plans to quit smoking in the next 6 months (but not in the next month) and an additional 31.6% planned to quit in the next month. Having a psychiatric condition was associated with nicotine use and higher motivation to quit smoking.

DISCUSSION AND CONCLUSIONS

Users of CTP are more likely to use nicotine products than the general population and the route of administration of nicotine products is related to the route of administration of CTP. If aerosolized CTP is a less harmful route of administration than smoked CTP, dispensary staff should be aware of this relationship and take this into account when recommending a noncombustible route.

SCIENTIFIC SIGNIFICANCE

This study further characterizes nicotine use behaviors and motivation to quit smoking among users of CTP and may be among the first to examine nicotine use among patients of a medical marijuana dispensary.

Differences in those who prefer smoking cannabis to other consumption forms for mental health: what can be learned to promote safer methods of consumption?

Smoking cannabis in medical users is associated with exposure to harmful toxins. It is important to characterize cannabis-use profiles and risk-factors for medical cannabis users who smoke cannabis. 100 members of a medical cannabis dispensary with mental health concerns were interviewed in detail about their cannabis use. Forty seven percent of participants preferred smoking only, 18% preferred vaporizing, 25% preferred both smoking and vaping, and 10% preferred oral ingestion methods. Smokers differed from other users in multiple ways, including a greater preference for THC-dominant chemovars, and more frequent and greater amount of cannabis consumption. Smoking was also associated with greater rates of alcohol use disorder. These results may inform harm-reduction approaches to decrease the number of individuals smoking cannabis and use less harmful methods of medical cannabis ingestion.

Prevalence and use of cannabis products and routes of administration among youth and young adults in Canada and the United States: A systematic review

BACKGROUND

The current systematic review aimed to summarize the literature on the prevalence of routes of administration and cannabis products used among youth and young adults in Canada and the United States (US).

METHODS

Five academic databases were searched in April 2020 and February 2021. Peer-reviewed articles were included if they were a population-based quantitative observational study describing the prevalence of a cannabis product or route of administration among youth and young adults in Canada or the US. Risk of bias was assessed using Hoy and colleagues' risk of bias assessment tool. A narrative review was conducted.

RESULTS

Twenty-six studies were identified for the following routes of administration: smoking (n = 16), vaping (n = 21), dabbing (n = 3), oral (n = 13), topical (n = 1); and products: dried flower (n = 2), and concentrates (n = 8). Smoking had the highest prevalence rates among youth and young adults; however, rates of use appeared to reduce over time. Conversely, prevalence of vaping appeared to increase over time. Fewer studies focused on oral or dabbed cannabis but those that did reported prevalence estimates of approximately a third among recent cannabis consumers.

DISCUSSION

The heterogeneity of cannabis routes of administration restricted our ability to collate average prevalence estimates. In jurisdictions where non-medical cannabis is legal, policymakers should provide guidance and education to youth on each type of product and routes of administration.

OTHER

Funding for this study was provided by a Canadian Institutes of Health Research (PJT-153342). The current review was registered with PROSPERO (CRD42020169275).

Cannabis for Medical Use: Versatile Plant Rather Than a Single Drug

Medical Cannabis and its major cannabinoids (−)-trans-Δ⁹-tetrahydrocannabinol (THC) and cannabidiol (CBD) are gaining momentum for various medical purposes as their therapeutic qualities are becoming better established. However, studies regarding their efficacy are oftentimes inconclusive. This is chiefly because Cannabis is a versatile plant rather than a single drug and its effects do not depend only on the amount of THC and CBD. Hundreds of Cannabis cultivars and hybrids exist worldwide, each with a unique and distinct chemical profile. Most studies focus on THC and CBD, but these are just two of over 140 phytocannabinoids found in the plant in addition to a milieu of terpenoids, flavonoids and other compounds with potential therapeutic activities. Different plants contain a very different array of these metabolites in varying relative ratios, and it is the interplay between these molecules from the plant and the endocannabinoid system in the body that determines the ultimate therapeutic response and associated adverse effects. Here, we discuss how phytocannabinoid profiles differ between plants depending on the chemovar types, review the major factors that affect secondary metabolite accumulation in the plant including the genotype, growth conditions, processing, storage and the delivery route; and highlight how these factors make Cannabis treatment highly complex.

Thermography of cannabis extract vaporization cartridge heating coils in temperature- and voltage-controlled systems during a simulated human puff

Vaporized cannabis is believed to be safer than smoking, but when heated to excessive temperatures nearing combustion (>900 °C) harmful byproducts may form. While some cannabis extract vaporizers operate well below these high temperatures, heating coil temperatures obtained during actual use are frequently not reported and many operate at high temperatures. We report on two major objectives: 1) development of an infrared thermography method to measure heating coil temperatures in cannabis extract vaporizers during a simulated puff and 2) a comparison of temperature- to voltage- controlled cannabis extract vaporization systems during a puff. Infrared thermography was used to measure heating coil temperatures in one temperature-controlled and two voltage-controlled systems. The cartridges were modified for direct line-of-sight on the heating coils, the wick and coils were saturated with cannabis extract, and fixtures were developed to force two liters per minute air flow past the coils for the full duration of the puff allowed by the device. The voltage-controlled systems produced higher temperatures with greater variability than the temperature-controlled system. At the highest temperature setting (420 °C) the temperature-controlled system reached an average heating coil temperature of 420 ± 9.5 °C whereas the 4.0V setting on the variable voltage system reached an average temperature of 543 ± 95.9 °C and the single voltage (3.2V) system an average of 450 ± 60.8 °C. The average temperature at the lowest setting (270 °C) on the temperature-controlled system was 246 ± 5.1 °C and the variable voltage system (2.4V) was 443 ± 56.1 °C. Voltage alone was a poor indicator of coil temperature and only the temperature-controlled system consistently maintained temperatures less than 400 °C for the full puff duration. These lower temperatures could reduce the likelihood of harmful thermal degradation products and thus may reduce potential health risk to consumers when vaporizing cannabis extracts.

A Clinical Framework for Assessing Cannabis-Related Impairment Risk

Clinicians play an important role in promoting safe and responsible medical cannabis use. One essential component to safe use is considering a patient's risk of neurocognitive impairment. However, there remains a lack of practical guidance on how clinicians can evaluate this risk for medical cannabis patients. Here, a practical framework is presented for clinicians to assess and stratify cannabis-associated impairment risk. The proposed framework is intended to practically guide healthcare providers in gaining a more comprehensive review of a patient's impairment-related factors. This framework can be used to assess impairment risk for patients currently using or considering medical cannabis and is recommended for all patients who perform safety-sensitive duties. Healthcare providers (HCP) managing patient's medical cannabis or those conducting assessments to determine risk of impairment for safety-sensitive workplaces can utilize this framework to stratify patients' risk of impairment. Such assessments can inform patient-specific needs for support, education, and guidance, to ensure cannabis is used safely and responsibly.

Elemental Analysis of Tetrahydrocannabinol and Nicotine E-Liquids Related to EVALI

During the e-cigarette, or vaping, product use-associated lung injury (EVALI) investigation, the U.S. FDA's Forensic Chemistry Center (FCC) received numerous sample submissions from various states and other sources. Many of these products were linked directly to patients, while others were not; both categories included used and unused products. Elemental analysis using inductively coupled plasma mass spectrometry (ICP-MS) preceded by microwave-assisted decomposition was carried out on the cartridge contents of 65 of these submitted samples. Challenges encountered included limited sample, high sample viscosity, and adhesion, which necessitated sample preparation techniques not commonly used during routine elemental analysis. The elemental concentrations of contaminants including Pb, As, Cd, Cr, Ni, Cu, and Sn in tetrahydrocannabinol (THC) e-liquids associated with EVALI were determined. Nicotine e-liquid samples collected alongside the THC e-liquid samples were analyzed in tandem during method development. Several THC e-liquid samples contained Pb greater than 0.5 μg/g, while others had part per million levels of Ni, Cu, and/or Cr. This study presents the first detailed report of elemental concentrations in multiple THC e-liquid samples including those from informal/illicit sources and also delves into the method considerations needed for testing a viscous, hydrophobic sample matrix in limited quantity.

Cannabis against chronic musculoskeletal pain: a scoping review on users and their perceptions

Background

Chronic musculoskeletal pain (CMP) may lead to reduced physical function and is the most common cause of chronic non-cancer pain. Currently, the pharmacotherapeutic options against CMP are limited and frequently consist of pain management with non-steroidal anti-inflammatories, gabapentinoids, or opioids, which carry major adverse effects. Although the effectiveness of medical cannabis (MC) for CMP still lacks solid evidence, several patients suffering from it are exploring this therapeutic option with their physicians.

Objectives

Little is known about patients’ perceptions of their MC treatment for CMP. We aimed to increase this knowledge, useful for healthcare professionals and patients considering this treatment, by conducting a scoping literature review, following guidance by Arksey and O’Malley, to describe the views and perceptions of adult patients who had consumed MC to relieve chronic CMP.

Methods

Databases (PUBMED, EMBASE, Web of Science) and websites were searched using combinations of controlled and free vocabulary. All studies and study designs reporting on patients’ perceptions regarding MC against CMP were considered. Studies had to include adult patients reporting qualitatively or quantitatively, i.e., through questionnaires, on MC use to treat CMP or other non-cancer pain, since studies reporting exclusively on perceptions regarding CMP were very rare. Study characteristics were extracted and limitations of the study quality were assessed. The review includes patients’ demographic characteristics, patterns of MC use, perceived positive and negative effects, use of alcohol or other drugs, reported barriers to CM use, and funding sources of the studies.

Results

Participants of the 49 included studies reported that MC use helped them to reduce CMP and other chronic non-cancer pain, with only minor adverse effects, and some reported improved psychological well-being.

In the included studies, men represent between 18 and 88% of the subjects. The mean age of participants in these studies (42/49) varied between 28.4 and 62.8 years old. The most common route of administration is inhalation.

Conclusion

MC users suffering from CMP or other chronic non-cancer pain perceived more benefits than harms. However, the information from these studies has several methodological limitations and results are exploratory. These user-reported experiences must thus be examined by well-designed and methodologically sound clinical or observational studies, particularly regarding CMP, where reports are very scarce.

Supplementary Information

The online version contains supplementary material available at 10.1186/s42238-021-00096-8.

Reasons for individual and concurrent use of vaped nicotine and cannabis: their similarities, differences, and association with product use

BACKGROUND

Understanding similarities, differences, and associations between reasons people vape nicotine and cannabis may be important for identifying underlying contributors to their co-use.

METHODS

A cross-sectional survey of 112 co-users of vaped nicotine and cannabis was conducted in 2020. A convenience sample of participants was recruited for the survey using Amazon Mechanical Turk. Participants responded to questions about their reasons for individual nicotine and cannabis product use and co-use and rated their level of agreement using numerical scales. Mean ratings for each reason for use subscale were examined across all participants and compared using paired samples t tests. Associations between reasons for use ratings and product consumption behaviors were examined using linear and logistic regression analyses.

RESULTS

Cannabis vaping and smoking exhibited similar mean ratings for user experience and product/substance-related reasons for use. Mean ratings for reasons related to product utility were similar for cannabis vaping and nicotine vaping. Mean ratings for utility-related reasons for use were higher for cannabis vaping than cannabis smoking (mean (SD), 3.6 (± 1.0) vs. 2.6 (± 1.2), p < 0.0001). On average, harm reduction-related reasons for use were rated higher for nicotine vaping than cannabis vaping (2.4 (± 1.6) vs. 1.8 (± 1.4), p < 0.0001). Regression models showed higher average ratings for utility-related (b = 0.32; 95% CI, 0.03-0.60) and harm reduction-related (b = 0.21; 95% CI, 0.04-0.37) reasons for nicotine vaping were associated with more frequent nicotine vaping (both p < 0.05). Higher average ratings for instrumentality-related reasons for co-use corresponded with more frequent monthly nicotine vaping (b = 0.26; 95% CI, 0.08-0.44) and higher odds of ever chasing cannabis with nicotine (aOR, 3.06; 95% CI, 1.29-7.30).

CONCLUSIONS

Vaping serves purposes that differ by substance; nicotine vaping was more closely related to reducing tobacco smoking-related harms, and cannabis vaping was more closely related to circumventing social problems posed by cannabis smoking. Lifetime sequential co-use practices and more frequent nicotine vaping were associated with enhancing the intoxicating effects of cannabis. While replication of these findings using non convenience-based sampling approaches is warranted, results underscore the need to consider shared and unique aspects of nicotine and cannabis vaping, as well as cross-substance interactions between nicotine and cannabis.

Chlorpyrifos and Δ9 Tetrahydrocannabinol exposure and effects on parameters associated with the endocannabinoid system and risk factors for obesity

Marilyn Silva. Retired from a career in toxicology and risk assessment. Increased childhood and adult obesity are associated with chlorpyrifos (CPF), an organophosphate pesticide. Cannabis (Δ9Tetrahydrocannabinol: Δ9THC) use has increased globally with legalization. CPF applications on cannabis crops lacks federally regulated tolerances and may pose health risks through exposure during development and in adulthood. Both CPF and Δ9THC affect the endocannabinoid system (eCBS), a regulator of appetite, energy balance, and gut microbiota, which, if disrupted, increases risk for obesity and related diseases. CPF inhibits eCB metabolism and Δ9THC is a partial agonist/antagonist at the cannabinoid receptor (CB1R). Effects of each on obesogenic parameters were examined via literature search. Male rodents with CPF exposure showed increased body weights, dysbiosis, inflammation and oxidative stress, potentially associated with increased eCBs acting through the gut-microbiota-adipose-brain regulatory loop. Δ9THC generally decreased body weights via partial agonism at the CB1R, lowering levels of eCBs. Dysbiosis and/or oxidative stress associated inflammation occurred with CPF, but these parameters were not tested with Δ9THC. Database deficiencies included limited endpoints to compare between chemicals/age-groups, inter-study variables (dose ranges, dosing vehicle, rodent strain, treatment duration, etc.). CPF and Δ9THC were not tested together, but human co-chemical effects would depend on exposure ratio, subject age, exposure duration, and health status, among others. An overriding concern is that both chemicals are well-documented developmental neurotoxins in addition to their low dose effects on energy balance. A co-exposure risk assessment is warranted with increased use and lack of federal CPF regulation on cannabis.

Self-administration of inhaled delta-9-tetrahydrocannabinol and synthetic cannabinoids in non-human primates

Cannabis and synthetic cannabinoids are abused in spite of possible adverse health consequences. The current study investigated the reinforcing effects of an ecologically relevant mode of administration (inhalation) of delta-9-tetrahydrocannabinol (THC), the primary psychoactive component of cannabis, and three synthetic cannabinoids detected in synthetic cannabinoid products (JWH-018, JWH-073, and HU-210) in non-human primates (NHPs). Male and female (N = 4 each) rhesus macaques were trained to inhale warm air via a metal stem to receive a candy reinforcer, an alcohol aerosol vehicle was then paired with the candy. Dose-dependent responding for inhaled aerosols of THC (2.0-16.0 μg/kg/inhalation), JWH-018 (0.2-1.6 μg/kg/inhalation), JWH-073 (2.0-8.0 μg/kg/inhalation), and HU-210 (1.0-8.0 μg/kg/inhalation) was established using a fixed-ratio five schedule of reinforcement and compared to vehicle (alcohol) self-administration. Dose-dependent responding for inhaled heroin (25.0-100.0 μg/kg/inhalation), a known reinforcer in NHPs, was also established. Responding approximated vehicle levels for many drug doses tested, but at least half of the monkeys responded for ≥ one dose of each cannabinoid and heroin above vehicle, with the exception of THC. Drug deliveries calculated as percent vehicle followed a prototypical inverted-U shaped dose-response curve for cannabinoids and heroin except for THC and JWH-018 (in males). Grouped data according to sex demonstrated that peak percent of vehicle reinforcers earned for THC was greater in males than females, whereas peak percent of vehicle reinforcers earned for JWH-018, HU-210, and heroin were greater in females than males. These findings indicate minimal reinforcing effects of CB1 receptor agonists when self-administered by NHPs via aerosol inhalation. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Regulatory Status of Pesticide Residues in Cannabis: Implications to Medical Use in Neurological Diseases

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Movement disorders are the most common neurological category of qualifying conditions in the U.S.

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The number and action levels of regulated pesticides in cannabis differ vastly in 33 states and Washington, D.C.

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Network analysis reveals potential interactions of insecticides, cannabinoids, and seizure at a functional level.

Medical cannabis represents a potential route of pesticide exposure to susceptible populations. We compared the qualifying conditions for medical use and pesticide testing requirements of cannabis in 33 states and Washington, D.C. Movement disorders were the most common neurological category of qualifying conditions, including epilepsy, certain symptoms of multiple sclerosis, Parkinson’s Disease, and any cause of symptoms leading to seizures or spasticity. Different approaches of pesticide regulation were implemented in cannabis and cannabis-derived products. Six states imposed the strictest U.S. EPA tolerances (i.e. maximum residue levels) for food commodities on up to 400 pesticidal active ingredients in cannabis, while pesticide testing was optional in three states. Dimethomorph showed the largest variation in action levels, ranging from 0.1 to 60 ppm in 5 states. We evaluated the potential connections between insecticides, cannabinoids, and seizure using the Comparative Toxicogenomics Database. Twenty-two insecticides, two cannabinoids, and 63 genes were associated with 674 computationally generated chemical-gene-phenotype-disease (CGPD) tetramer constructs. Notable functional clusters included oxidation-reduction process (183 CGPD-tetramers), synaptic signaling pathways (151), and neuropeptide hormone activity (46). Cholinergic, dopaminergic, and retrograde endocannabinoid signaling pathways were linked to 10 genetic variants of epilepsy patients. Further research is needed to assess human health risk of cannabinoids and pesticides in support of a national standard for cannabis pesticide regulations.

Effects of Cannabis Consumption on Sleep

Despite the fact that medical properties of Cannabis have been recognized for more than 5000 years, the use of Cannabis for medical purposes have recently reemerged and became more accessible. Cannabis is usually employed as a self-medication for the treatment of insomnia disorder. However, the effects of Cannabis on sleep depend on multiple factors such as metabolomic composition of the plant, dosage and route of administration. In the present chapter, we reviewed the main effect Cannabis on sleep. We focused on the effect of "crude or whole plant" Cannabis consumption (i.e., smoked, oral or vaporized) both in humans and experimental animal models.The data reviewed establish that Cannabis modifies sleep. Furthermore, a recent experimental study in animals suggests that vaporization (which is a recommended route for medical purposes) of Cannabis with high THC and negligible CBD, promotes NREM sleep. However, it is imperative to perform new clinical studies in order to confirm if the administration of Cannabis could be a beneficial therapy for the treatment of sleep disorders.

Marijuana and Bariatric Surgery

PURPOSE OF REVIEW

Marijuana use presents a unique challenge to bariatric surgery programs. We review the recent evidence examining marijuana use on outcomes following bariatric surgery.

RECENT FINDINGS

Recent studies have not demonstrated an increased risk of short-term surgical complications or differences in up to 2-year weight loss following surgery among marijuana users. However, studies have demonstrated increased risks in two areas: pain management and problematic eating behaviors. Additionally, preoperative marijuana use has been linked to increased postoperative marijuana use which may undermine weight loss and increase risk for weight regain. There are still many unanswered questions regarding marijuana use and bariatric surgery, and the limited literature base has produced mixed results when considering marijuana as a contraindication for bariatric surgery. Programs must take into consideration the laws of their state, individual patterns of use, and route of administration when considering whether marijuana is a contraindication for surgery.

Cannabis Consumption, Purchasing and Sources among Young Canadians: The Cannabis Purchase and Consumption Tool (CPCT)

BACKGROUND

Despite its extensive use, there is a paucity of research on consumption and purchasing patterns of cannabis, especially by modes of delivery.

OBJECTIVE

To assess the self-reported use and frequency of use of 12 different cannabis modes of delivery, their associated purchase sources, self-reported price, average consumption amount, and knowledge of THC and CBD levels.

METHODS

The Cannabis Purchase and Consumption Tool, an online survey, sampled Canadians 16-30 years old (N = 868) in October 2017. Final sample included participants reporting use of any mode of cannabis within the past 30-days (N = 185).

RESULTS

The most common modes of delivery were dried herb that was either smoked or vaporized, and cannabis edibles. Use of hashish, hash oil and other concentrates followed, while liquids, tinctures, topical ointments, and fresh flower/leaf were used less frequently. Average dried herb consumption was 17.8 g/month, 17.4 g/month, and 9.4 g/month among licensed medical, non-licensed medical, and non-medical cannabis users, respectively. At last time of purchase, participants paid an average of $17.97/gram for dried herb. 31.5% of current users reported knowing THC and 13.2% CBD levels of their cannabis.

CONCLUSIONS

Youth and young adults report a wide diversity of cannabis products and modes of administration. Traditional measures that rely primarily on frequency of use may be inadequate to assess the rapidly evolving cannabis market, particularly given policy changes, including legalization of non-medical cannabis.

Development of a Vaping Machine for the Sampling of THC and CBD Aerosols Generated by Two Portable Dry Herb Cannabis Vaporisers

Cannabis sativa is known for its recreational use, but also for its therapeutic potential. There has been wide discussion over the use of cannabis for medical purposes in recent years, especially because a consensus has not been reached regarding its risk/benefit balance. Among the more common modes of administration, vaping with a vaporiser is most frequently used for self-medication. Vaping seems to be a better alternative to preventing adverse health effects due to toxic compounds produced during combustion when cannabis is smoked. However, the delivery kinetics and efficiency of most portable vaporisers are not fully characterised with an appropriate vaping regime. This determination requires a specific vaping machine operating under realistic puffing conditions. In this study, a vaping machine was conceived to fit with the common uses of portable vaporisers that requires conditions different from those used for electronic cigarettes. The experimental setup in this study was optimised to sample aerosolised cannabinoids. The delivery kinetics, efficiency, and decarboxylation yields of two commercially available vaporisers (DaVinci® and Mighty Medic®) were evaluated for delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Among all tested sampling supports, the glass fibre filter is the most efficient medium to collect mixed THC and CBD aerosols. From the delivery kinetics of cannabinoids, a single-parameter model was used to calculate the extraction coefficient of each vaporiser. The results show that the Mighty Medic® vaporiser had a higher extraction coefficient (0.39) and a more immediate release of cannabinoids than the DaVinci® vaporiser (0.16), which had a gradual and slower rate of vaporisation. This parameter could be a quantitative input in pharmacokinetic models of administration of volatile compounds using vaporisers and a useful tool for the comparison of vaporisers.

Oral Administration of Cannabis and Δ-9-tetrahydrocannabinol (THC) Preparations: A Systematic Review

BACKGROUND AND OBJECTIVE

Changes in cannabis legalization regimes in several countries have influenced the diversification of cannabis use. There is an ever-increasing number of cannabis forms available, which are gaining popularity for both recreational and therapeutic use. From a therapeutic perspective, oral cannabis containing Δ-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) is a promising route of administration but there is still little information about its pharmacokinetics (PK) effects in humans. The purpose of this systematic review is to provide a general overview of the available PK data on cannabis and THC after oral administration.

METHODS

A search of the published literature was conducted using the PubMed database to collect available articles describing the PK data of THC after oral administration in humans.

RESULTS

The literature search yielded 363 results, 26 of which met our inclusion criteria. The PK of oral THC has been studied using capsules (including oil content), tablets, baked goods (brownies and cookies), and oil and tea (decoctions). Capsules and tablets, which mainly correspond to pharmaceutical forms, were found to be the oral formulations most commonly studied. Overall, the results reflect the high variability in the THC absorption of oral formulations, with delayed peak plasma concentrations compared to other routes of administration.

CONCLUSIONS

Oral THC has a highly variable PK profile that differs between formulations, with seemingly higher variability in baked goods and oil forms. Overall, there is limited information available in this field. Therefore, further investigations are required to unravel the unpredictability of oral THC administration to increase the effectiveness and safety of oral formulations in medicinal use.

Acute neuroradiological, behavioral, and physiological effects of nose-only exposure to vaporized cannabis in C57BL/6 mice

Objective: The rapid increase of cannabis consumption reinforces the need to elucidate the health hazards of this practice. The presence of fine particulate matter in cannabis smoke and vapor poses a major concern, as it may contribute to cardiopulmonary disease. To facilitate the assessment of risks associated with cannabis inhalation, we developed and characterized a method for exposing mice to cannabis in a way that mimics the delivery of the drug to the airways of smokers. Materials and Methods: Cannabis (10.3% THC, 0.05% CBD) was vaporized to generate aerosols with a reproducible particle profile. Aerosols were acutely delivered to male, adult C57BL/6 mice via a nose-only exposure system. Serum THC levels were measured for increasing cannabis doses. Blood pressure and heart rate were recorded at baseline and following exposure. Behavioral response to cannabis inhalation in the open field was documented. Awake neurological activity upon cannabis exposure was monitored using BOLD fMRI.Results and Discussion: Cannabis aerosols contained particles with count median diameter of 243 ± 39 nm and geometric standard deviation of 1.56 ± 0.06. Blood serum THC levels increased linearly with aerosolized mass and peaked at 136 ± 5 ng/mL. Cannabis inhalation decreased heart rate and blood pressure but promoted anxiety-like behavior. Observed differences in BOLD activation volumes linked cannabis to increased awareness to sensory stimuli and reduced behavioral arousal.Conclusions: Quantified physiological, behavioral, and neurological responses served as validation for our mouse model of cannabis inhalation. Animal models of aerosol exposure will be instrumental for uncovering the health outcomes of chronic cannabis use.

The Prevalence of Vaping and Smoking as Modes of Delivery for Nicotine and Cannabis among Youth in Canada, England and the United States

Background: Vaping has become an increasingly common mode of administration for both nicotine and cannabis, with overlap among users, devices, as well as nicotine and cannabis companies. There is a need to understand patterns of use among youth, including the way nicotine and cannabis are administered. Methods: Data are from Wave 2 of the ITC Youth Tobacco and Vaping survey, an online survey conducted in 2018 among 16-19 year-olds recruited from commercial panels in Canada (n = 3757), England (n = 3819), and the U.S. (n = 3961). The prevalence of past 30-day vaping nicotine, non-nicotine and cannabis substances, as well as cannabis modes of use was examined. Logistic regression models examined between country differences in prevalence. Results: Past 30-day cannabis use was highest among Canadian youth (16.6%), followed by youth in the U.S. (13.8%) and England (9.0%). Vaping e-cigarettes was substantially more prevalent than vaping cannabis in all three countries. All forms of cannabis use were higher among Canadian and U.S. youth compared to England (p < 0.001 for all). Past 30-day cannabis users in the U.S. were more likely to report vaping cannabis oil (30.1%), and consuming solid concentrates such as wax and shatter (30.2%), compared to cannabis users in Canada (18.6% and 22.9%) and England (14.3% and 11.0%; p < 0.001 for all). Conclusions: Youth are administering cannabis and nicotine using a wide diversity of modes. Cannabis users in the U.S.-where an increasing number of states have legalized medical and non-medical cannabis-reported notably higher use of more potent cannabis products, including cannabis oils and extracts.

Vaporized Cannabis differentially modulates sexual behavior of female rats according to the dose

Studies exploring the effect of compounds that modulate the endocannabinoid system on sexual behavior have yielded contradictory results. However, the effect of smoked Cannabis in women has been consistently associated with an increase in sexual drive. Therefore, it can be speculated that vaporized Cannabis will augment sexually motivated components of the sexual behavior of female rats. To test this hypothesis, we compared the sexual behavior of late-proestrous female rats in a bilevel chamber after vaporizing 0, 200 or 400 mg of Cannabis flowers (containing 18% of delta-9-THC and undetectable levels of cannabidiol) during 10 min. We found that both doses of Cannabis increased the duration of the lordosis response, whereas the highest dose also reduced the lordosis quotient of females. The lowest dose of Cannabis augmented the display of hops and darts without altering the expression of sexual solicitations of females, while the highest one did not affect the expression of hops and darts but reduced sexual solicitations. These effects were not accompanied by alterations of females' ambulatory behavior. The increment of the duration of lordosis response produced by both doses of Cannabis could be associated to a general effect of this drug in sensory processing, as can be an enhancement of females' sensory reactivity to male's stimulation. However, the reduction in the display of solicitations and lordosis in response to mounting observed in females exposed to the highest dose when compared to control and 200 mg of Cannabis groups indicates a reduction of sexual receptivity and motivation. This differential effect of vaporized Cannabis according to the dose employed, suggests that it modulates sexual behavior in a complex way, impacting neural circuits that control different aspects of this social behavior.

A Novel Self-Emulsifying Drug Delivery System (SEDDS) Based on VESIsorb® Formulation Technology Improving the Oral Bioavailability of Cannabidiol in Healthy Subjects

Cannabidiol (CBD), a phytocannabinoid compound of Cannabis sativa, shows limited oral bioavailability due to its lipophilicity and extensive first-pass metabolism. CBD is also known for its high intra- and inter-subject absorption variability in humans. To overcome these limitations a novel self-emulsifying drug delivery system (SEDDS) based on VESIsorb^® formulation technology incorporating CBD, as Hemp-Extract, was developed (SEDDS-CBD). The study objective was to evaluate the pharmacokinetic profile of SEDDS-CBD in a randomized, double-blind, cross-over design in 16 healthy volunteers under fasted conditions. As reference formulation, the same Hemp-Extract diluted with medium-chain triglycerides (MCT-CBD) was used. CBD dose was standardized to 25 mg. Pharmacokinetic parameters were analyzed from individual concentration-time curves. Single oral administration of SEDDS-CBD led to a 4.4-fold higher C_max and a 2.85-/1.70-fold higher AUC_0–8h/AUC_0–24h compared to the reference formulation. T_max was substantially shorter for SEDDS-CBD (1.0 h) compared to MCT-CBD (3.0 h). Subgroup analysis demonstrated a higher bioavailability in women compared to men. This difference was seen for MCT-CBD while SEDDS-CBD mitigated this gender effect. Overall, SEDDS-CBD showed a significant improvement for all determined pharmacokinetic parameters: increased CBD plasma values (C_max), favorably enhanced bioavailability (AUC) and fast absorption (T_max). No safety concerns were noted following either administration.

Denying renal transplantation to an adolescent medical cannabis user: An ethical case study

Medical cannabis is now legal in over half of the United States. As more patients adopt this unconventional therapy, it is inevitable that potential transplant recipients will disclose their cannabis use during transplant evaluation. Transplant teams are tasked with the decision to utilize a pressure resource, often with little guidance from international and national professional organizations. Many healthcare providers remain uniformed or misinformed about the risks of cannabis use and organ transplantation. In order to illustrate the multifaceted and complex evaluation of transplant patients using medical cannabis, this article presents the case of a 20-year-old woman recommended for renal transplant who was originally denied active listing due to her medical cannabis use. A review of the literature explores the perceived and actual risks of cannabis use in the immunocompromised patient. Furthermore, a discussion of the ethics of medical cannabis use and organ transplantation is included with recommendations for multidisciplinary transplant teams.

A qualitative analysis of cannabis vaporization among medical users

Cannabis vaporization is a prevailing mode of administration among medical users for symptom relief. Limited research to date has considered factors that contribute to vaporization in medical users, although initial evidence suggests that vaporization may provide unique therapeutic advantages relative to other modes. This study aimed to provide an in-depth qualitative examination of vaping behavior and use preferences among medical cannabis users. Qualitative interviews were conducted with Rhode Island medical cannabis registration card holders (n = 25). Interviews followed a semistructured agenda and were audio-recorded and transcribed for applied thematic analysis. Key vaporization themes were summarized. Several themes emerged related to (a) medication dosing and administration (flexible timing of medication delivery; ease when traveling; type of device/cannabis formulation), (b) physical health advantages of vaping (general health benefits; better for medical condition; promoting tobacco cessation), (c) general advantages of vaping (portability, concealability, efficiency), and (d) disadvantages (weaker medication delivery; device cost; technology-use barriers). Various factors contribute to cannabis vaporization among medical users that are both general and medical-specific. Certain aspects of vaping may also interfere with effective delivery of cannabis, including technology aspects and device cost. These findings highlight the heterogeneity in vaporization behavior. Future work is needed to further identify factors that contribute to the therapeutic efficacy of cannabis and its modalities of use. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Adverse outcome pathway of developmental neurotoxicity resulting from prenatal exposures to cannabis contaminated with organophosphate pesticide residues

There is growing concern that increased use of medical and recreational cannabis may result in increased exposure to contaminants on the cannabis, such as pesticides. Several states are moving towards implementing robust regulation of the sales, cultivation, and manufacture of cannabis products. However, there are challenges with creating health-protective regulations in an industry that, to date, has been largely unregulated. The focus of this publication is a theoretical examination of what may happen when women are exposed pre-conceptually or during pregnancy to cannabis contaminated with pesticides. We propose an adverse outcome pathway of concomitant prenatal exposure to cannabinoids and the organophosphate pesticide chlorpyrifos by curating what we consider to be the key events at the molecular, cellular, and tissue levels that result in developmental neurotoxicity. The implications of this adverse outcome pathway underscore the need to elucidate the potential developmental neurotoxicity that may result from prenatal exposure to pesticide-contaminated cannabis.

Is medical marijuana legalisation possible in Poland?

OBJECTIVES

In some countries of the world it is legal to use plant-based marijuana for therapeutic purposes. When we had learned that 7,000 petitioners (including doctors) signed the petition to enable access to marijuana for patients in the Czech Republic, we decided to examine the knowledge about marijuana's medical properties among Polish medical students.

METHODS

Anonymous questionnaire study was conducted on a group of 181 of students of the last (sixth) year of medical school.

RESULTS

It was demonstrated that students are not provided with sufficient information about therapeutic administration of plant-based marijuana during medical studies. The majority of interviewees mentioned only one indication for medical marijuana use. All students did not interchange medical conditions for which marijuana is used in 30 USA states or Canada.

DISCUSSION

Marijuana smoking for medical purposes differs from recreational smoking, and its effect does not depend on occurrence of symptoms from the central nervous system. Few studies, that were carried out along with numerous previously unreported cases of patients, demonstrated that plant-derived marijuana had therapeutic effect on many diseases where conventional medicine was of no help.

CONCLUSION

All doctors, including medical students, should receive more information about the therapeutic properties of marijuana.

E-cigarettes-An unintended illicit drug delivery system

Since the introduction of electronic cigarettes (e-cigarettes) in 2003, the technology has advanced allowing for greater user modifications, with users now able to control voltage, battery power, and constituents of the e-cigarette liquid. E-cigarettes have been the subject of a growing body of research with most research justifiably focused on the chemical makeup and risk analysis of chemicals, metals, and particulates found in e-cigarette liquids and vapor. Little research to date has focused on assessing the risks associated with the drug delivery unit itself and its potential for use as an illicit drug delivery system. In light of this, a range of illicit drugs was researched focusing on pharmacodynamics, usual method of administration, the dosage required for toxicity, toxic effects, and evidence of existing use in e-cigarettes in both literature and online illicit drug forums. A systematic literature search found evidence of current use of e-cigarettes to vape almost all illicit drug types analyzed. This presents both a potential population health risk and a management issue for clinicians. It also raises the issue of policing illicit drugs due to potential altered characteristic smells and storage within e-cigarette fluids. E-cigarettes are a viable illicit drug delivery system with evidence both inside and outside of the formal medical literature detailing their potential use for drug delivery of a wide range of illicit and legal drugs.