Ethanol increases plasma Delta(9)-tetrahydrocannabinol (THC) levels and subjective effects after marihuana smoking in human volunteers

Alcohol and cannabis use in daily lives of college-attending young adults: Does co-use correspond to greater reported pleasure?

Co-use of alcohol and cannabis is prevalent and linked with heightened risk for substance-related harms. The current study investigated the role of substance-related pleasure as a reinforcing factor for co-use relative to alcohol or cannabis use. Specifically, we used data from a 21-day diary study of college students to examine day-level associations between co-use and self-reported substance-related pleasure (any, level of pleasure). Participants were 237 college students (65 % female sex at birth, ages 18-24) who reported 1+ alcohol and cannabis co-use occasion. Participants completed daily surveys across 21 consecutive days about yesterday's substance use and experiences of pleasure, yielding 2,086 daily surveys involving alcohol and/or cannabis use. Multilevel models indicated that odds of substance-related pleasure were higher on days with co-use relative to days with single-substance use, and level of pleasure was higher on co-use days relative to cannabis but not alcohol use days. Pleasure may serve as a reinforcing property of co-use that may be related to continued use despite experience of negative consequences. Intensity of pleasure related to co-use appears to be largely driven by use of alcohol. However, given mixed findings concerning level of pleasure, individuals may report co-use increases feelings of pleasure but do not actually experience more pleasure. Pleasure may serve as a viable target in future prevention and intervention programming targeting co-use.

Trajectories of polysubstance use: Are past-year internalizing and externalizing problems associated with trajectories of polysubstance use over time?

OBJECTIVE

Polysubstance use among adults has been a public health concern in the U.S. and is associated with adverse consequences. This study aimed to identify the longitudinal trajectory of polysubstance use and test whether internalizing and externalizing problems predict it.

METHODS

Data of adults aged 18 and older (N = 15076) were extracted from the Waves 1-5 Population Assessment of Tobacco and Health Study (2013-2019). Group-Based Trajectory Modeling was performed to identify the trajectory of polysubstance use. Examined substances included use of cigarettes, e-cigarettes, excessive alcohol, cannabis, painkillers, and cocaine in past 30 days from all waves. Weighted multinomial logistic regressions were conducted to investigate the associations between internalizing and externalizing problems and the trajectory of polysubstance use, controlling for demographic variables.

RESULTS

Five trajectory groups were identified: (1) No to minimal polysubstance use risk (45.6 %); (2) Polysubstance use-low risk (10.7 %); (3) Cigarette-leading polysubstance use-high risk (23.5 %); (4) Cigarette-cannabis co-leading polysubstance use-high risk (12.3 %); and (5) Cannabis-leading polysubstance use-high risk (7.8 %). Compared with Group 1, higher internalizing problems predicted the membership of Group 3 [Relative risk ratio (RRR) range: 1.07-1.17] and Group 4 (RRR range: 1.04-1.21). Compared with Group 1, higher externalizing problems predicted the membership of Group 5 (RRR range: 1.01-1.10).

CONCLUSIONS

Prevention efforts should consider internalizing problems and associated trajectories of high-risk polysubstance use (e.g., cigarette-leading and cigarette-cannabis co-leading) as well as externalizing problems and associated trajectories of high-risk polysubstance use (e.g., cannabis-leading), when designing interventions to prevent polysubstance use.

Alcohol and cannabis co-use: Probing subjective response in eliciting cross-substance craving

The co-use of alcohol and cannabis is rising in prevalence, yet the mechanisms driving individuals to co-use are not well understood. Subjective response to alcohol or cannabis may predict the desire to use either substance. However, which specific facets of subjective response predict cross-substance craving remains unclear. The present study investigated whether acute administration of alcohol or cannabis facilitates cue-induced craving for the other substance, with an emphasis on the underlying subjective response mechanisms contributing to co-use. This is a secondary analysis of a behavioral pharmacology study that combined alcohol/cannabis administration with a cross-substance cue-reactivity paradigm in individuals who were heavy alcohol and heavy cannabis co-users. Over two sessions, twenty-nine individuals (17M/12F) self-administered alcohol or cannabis (in a crossover design), and then completed a cue-reactivity exercise with the other substance. Analyses tested how changes in subjective response variables following substance administration predicted cross-substance cue-induced craving. Following alcohol administration, greater subjective ratings of positive mood predicted significantly greater cue-induced cannabis craving (β = 1.14, SE = 0.41, t = 2.80, p = 0.010). Following cannabis administration, lower subjective effects ratings of positive mood/arousal predicted significantly greater cue-induced alcohol craving (β = -1.08, SE = 0.38, t = -2.85, p = 0.009; β = -2.38, SE = 1.13, t = -2.10, p = 0.047). This study identified subject response mechanisms contributing to cross-substance cue induced craving. These mechanisms include increases in positive mood following alcohol use and decreases in positive mood and arousal, akin to increases in relaxation, following cannabis use.

Within-episode relations among simultaneous alcohol and cannabis use and continued drinking: The role of momentary subjective responses, craving, and drinking context

BACKGROUND

Simultaneous alcohol and cannabis use is associated with riskier daily drinking. However, little research has tested momentary mechanisms through which simultaneous use predicts continued drinking during acute drinking episodes. The current study tested whether simultaneous use moments predicted within-episode increases in subjective responses, craving, and continued drinking, and whether these relations were potentiated in social versus solitary settings.

METHODS

Emerging adults who co-use alcohol and cannabis (N = 85) completed 21 days of ecological momentary assessment with event-contingent reports during drinking episodes. Three-level multilevel models tested whether simultaneous (vs. alcohol-only) use moments indirectly predicted subsequent, continued drinking through subjective responses (i.e., high-arousal positive/stimulant, high-arousal negative/aggression, low-arousal positive/relaxation, low-arousal negative/impairment) and alcohol craving, and whether relations differed by social versus solitary contexts.

RESULTS

Within drinking episodes, simultaneous (vs. alcohol-only) use moments were associated with increased stimulation, which was indirectly associated with continued drinking through increased alcohol craving. Additionally, the relation between simultaneous (vs. alcohol-only) use and stimulating effects was potentiated during solitary drinking moments, whereas the relation between stimulating effects and craving was potentiated during social drinking moments. However, stimulating effects were higher in social contexts across all moments. Finally, simultaneous (vs. alcohol-only) use moments were associated with increased relaxation, which was indirectly associated with a lower likelihood of continued drinking through lesser craving.

CONCLUSIONS

Simultaneous use predicted both continued within-episode drinking and cessation of drinking, with acute subjective effects and craving as mechanisms, dependent upon context. Just-in-time interventions should consider targeting affect, craving, and context in event-specific interventions.

Examining the Impact of Simultaneous Alcohol and Cannabis Use on Alcohol Consumption and Consequences: Protocol for an Observational Ambulatory Assessment Study in Young Adults

BACKGROUND

There is significant conflicting evidence as to how using cannabis while drinking alcohol (ie, simultaneous alcohol and cannabis use) impacts alcohol volume consumed, patterns of drinking, and alcohol-related consequences. The impact of simultaneous use on drinking outcomes may be influenced by several within-person (eg, contextual) and between-person (individual) factors.

OBJECTIVE

This study was designed to examine naturalistic patterns of alcohol and cannabis use to understand how simultaneous use may impact drinking outcomes. The primary aims were to understand the following: (1) if simultaneous use is associated with increased alcohol consumption and riskier patterns of drinking, (2) if simultaneous use leads to increased alcohol consequences, and (3) how contextual circumstances moderate the impact of simultaneous use on consumption and consequences.

METHODS

Data collection involves a 28-day ambulatory assessment protocol in which a sample of non-treatment-seeking young adults who report simultaneous use of alcohol and cannabis complete ecological momentary assessments (random, event-contingent, and time-contingent surveys) of alcohol and cannabis use, contexts, motives, and consequences on their personal smartphones while continuously wearing an alcohol biosensor bracelet. Participants also complete a baseline assessment, brief internet-based check-in on day 14, and a final session on day 28. Community-based recruitment strategies (eg, social media and flyers) were used to enroll 95 participants to obtain a target sample of 80, accounting for attrition.

RESULTS

Recruitment and data collection began in May 2021 and continued through June 2024. Initial results for primary aims are expected in October 2024. As of March 2024, the project had recruited 118 eligible participants, of whom 94 (79.7%) completed the study, exceeding initial projections for the study time frame. Remaining recruitment will provide the capacity to probe cross-level interactions that were not initially statistically powered. Strengths of the project include rigorous data collection, good retention and compliance rates, faster-than-expected enrollment procedures, use of a novel alcohol biosensor, and successful adaptation of recruitment and data collection procedures during the COVID-19 pandemic.

CONCLUSIONS

This is the first investigation to assess the key momentary predictors and outcomes of simultaneous use as well as self-reported and objective (via alcohol biosensor) measures of alcohol consumption and patterns. The results of this study will inform prevention efforts and studies of individuals who use cannabis who are engaged in alcohol treatment.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/58685.

Simultaneous Alcohol and Cannabis Use and High-Risk Sexual Behaviors

Background

Alcohol and cannabis use rates are highest in college-aged young adults, and both alcohol and cannabis use are independently related to high-risk sexual behaviors (HRSBs). HRSBs (e.g., sex without protection against sexually transmitted infections) are a prevalent public health problem in college students, with little research examining simultaneous alcohol and cannabis use (i.e., using both alcohol and cannabis at the same time so the effects overlap) and HRSBs.

Method

We examined simultaneous alcohol and cannabis-related HRSB frequency, gender differences in simultaneous alcohol and cannabis-related HRSBs, and differences in HRSBs between simultaneous and non-simultaneous users. Alcohol and cannabis using college students (N = 534; Average Age = 19; 66.9% reported identifying as female) were recruited through a psychology department's human subjects research pool and completed a one-time, online, self-report survey.

Results

One-third of participants engaged in simultaneous alcohol and cannabis use prior to sexual intercourse in the past 3 months. Additionally, over one-third of participants reported heavy drinking (4/5 or more drinks for women/men) simultaneously with cannabis use prior to sexual intercourse in the past 3 months. Simultaneous alcohol and cannabis use was significantly and positively related to sexual intercourse after simultaneous use and after heavy drinking simultaneously with cannabis use. Past year simultaneous alcohol and cannabis users, relative to non-simultaneous users, reported increased incidents of sex without protection against sexually transmitted infections. No gender differences in simultaneous alcohol and cannabis-related HRSBs were found.

Conclusions

Future research should continue examining simultaneous alcohol and cannabis use and HRSBs.

The effects of simultaneous alcohol and cannabis use on subjective drug effects: A narrative review across methodologies

Over 75% of young adults who use cannabis also report drinking alcohol, leading to increased risks that include impaired cognition, substance use disorders, and more heavy and frequent substance use. Studies suggest that subjective responses to either alcohol or cannabis can serve as a valuable indicator for identifying individuals at risk of prolonged substance use and use disorder. While laboratory studies show additive effects when alcohol and cannabis are used together, the impact of co-using these substances, specifically with respect to cannabidiol, on an individual's subjective experience remains unclear. This narrative review explores the effects of simultaneous alcohol and cannabis (SAM) use on subjective drug effects, drawing from qualitative research, laboratory experiments, and naturalistic studies. Experimental findings are inconsistent regarding the combined effects of alcohol and cannabis, likely influenced by factors such as dosage, method of administration, and individual substance use histories. Similarly, findings from qualitative and naturalistic studies are mixed regarding subjective drug effects following SAM use. These discrepancies may be due to recall biases, variations in assessment methods, and the measurement in real-world contexts of patterns of SAM use and related experiences. Overall, this narrative review highlights the need for more comprehensive research to understand more fully subjective drug effects of SAM use in diverse populations and settings, emphasizing the importance of frequent and nuanced assessment of SAM use and subjective responses in naturalistic settings.

Evolving Disparities in Cannabis Use Among Youth by Demographics and Tobacco and Alcohol Use in the U.S.: 2013-2021

INTRODUCTION

This study investigated the prevalence of past 30-day cannabis use among U.S. youth by cigarette use, alcohol use, demographics, and state-of-residence cannabis legal status in 2021 and examined whether changes in cannabis use prevalence were modified by these factors from 2013 to 2021.

METHODS

Data were drawn from the 24 states that collected cannabis use data participating in the Youth Risk Behavior Surveillance System from 2013 to 2021. Logistic regression analyses estimated past 30-day cannabis prevalence in 2021 and produced AORs by current cigarette, alcohol, and state-of-residence cannabis legal status. The same method was used with year as the exposure, adjusting for sex, race, and ethnicity, to assess trends in prevalence from 2013 to 2021.

RESULTS

In 2021, cannabis use was more common among female youth (16.75% vs 13.83% [AOR=1.26, 95% CI=1.16, 1.37]) and non-Hispanic Black and Hispanic youth than among non-Hispanic White youth (17.19%, 16.14% vs 14.60% [AOR=1.25, 95% CI=1.12, 1.39 and AOR=1.16, 95% CI=1.04, 1.29, respectively]). Cannabis use was much more common among youth who reported any past 30-day cigarette or alcohol use (44.90% vs 6.48% [AOR=11.80, 95% CI=10.57, 13.18]). Declines in cannabis use were observed independent of state-level cannabis law from 2013 to 2021, and cannabis use prevalence did not differ significantly by state-of-residence cannabis legal status among the 24 participating states in 2021.

CONCLUSIONS

Public health officials should carefully consider the potential impact of expanding commercialization of cannabis as a wellness product on youth cannabis use, especially with regard to minoritized populations and co-use with tobacco and alcohol. National and state-level public health education on cannabis use and youth-oriented prevention of cannabis uptake are long overdue.

Interactive effects of alcohol and cannabis quantities in the prediction of same-day negative consequences among young adults

BACKGROUND

Simultaneous alcohol and cannabis use is common, but observational studies examining negative consequences of simultaneous use have rarely considered dose-related interactions between alcohol and cannabis. This study examined interactions between quantities of cannabis and alcohol consumed in predicting negative consequences on simultaneous use days.

METHODS

Young adults (N = 151; 64% female; 62% White) reporting recent simultaneous use and at least weekly alcohol and cannabis use completed 21 daily, smartphone-based surveys assessing previous day quantities of cannabis and alcohol used, types of cannabis used (flower, concentrates, edibles), and negative substance-related consequences. Multilevel models examined: (1) whether negative consequences differed within-person across simultaneous use days and single-substance use days; and (2) whether quantities of alcohol and cannabis consumed on simultaneous use days interacted, within-person, to predict negative consequences. We focused on quantities of cannabis flower (grams) in primary analyses and explored quantities of other forms of cannabis (concentrates, edibles) in supplementary analyses.

RESULTS

Participants reported fewer negative consequences on alcohol-only (243 observations) and cannabis-only (713 observations) days than they did on simultaneous use days (429 observations). On simultaneous use days involving cannabis flower use (313 observations across 81 participants), the within-person association between number of standard drinks and negative consequences was weaker on days during which larger (vs. smaller) amounts of cannabis flower were consumed. Inspection of simple slopes revealed that decreased alcohol use was associated with less of a decline in negative consequences when combined with relatively greater amounts of cannabis flower.

CONCLUSIONS

Although simultaneous use was associated with more negative consequences than alcohol-only and cannabis-only use, negative consequences on simultaneous use days varied as a function of the interaction between alcohol and cannabis quantities. As findings suggest that using larger amounts of cannabis may attenuate declines in negative consequences associated with lighter drinking, interventions for higher-risk simultaneous use patterns may benefit from a focus on quantities of both alcohol and cannabis.

Simultaneous Cannabis and Alcohol Use among Medical Cannabis Patients

Background: During the past two decades of cannabis legalization, the prevalence of medical cannabis (MC) use has increased and there has also been an upward trend in alcohol consumption. As less restricted cannabis laws generate more adult cannabis users, there is concern that more individuals may be simultaneously using medical cannabis with alcohol. A few studies have examined simultaneous use of medical cannabis with alcohol, but none of those studies also assessed patients' current or previous non-medical cannabis use. This paper explores simultaneous alcohol and medical cannabis use among medical cannabis patients with a specific focus on previous history of cannabis use and current non-medical cannabis use. Methods: A retrospective cohort study of MC patients (N = 319) from four dispensaries located in New York. Bivariate chi-square tests and multivariable logistic regression are used to estimate the extent to which sociodemographic and other factors were associated with simultaneous use. Results: Approximately 29% of the sample engaged in simultaneous use and a large share of these users report previous (44%) or current (66%) use of cannabis for non-medical purposes. MC patients who either previously or currently use cannabis non-medicinally, men, and patients using MC to treat a pain-related condition, were significantly more likely to report simultaneous alcohol/MC use. Conclusions: Findings indicate that there may be differential risks related to alcohol/MC use, which should be considered by cannabis regulatory policies and prevention/treatment programs. If patients are using cannabis and/or alcohol to manage pain, clinicians should screen for both alcohol and cannabis use risk factors.

Sex and Gender Differences in Simultaneous Alcohol and Cannabis Use: a Narrative Review

Purpose of Review

The aim is to review recent literature on sex and gender differences in patterns of use, motives, pharmacological effects, and consequences of simultaneous alcohol and cannabis use (SAC).

Recent Findings

Men engage in SAC more frequently than women. Women may have more substance-specific motives for use, while men tend to consistently endorse social/enhancement motives for both alcohol and cannabis. Regarding pharmacological effects, women experience the same subjective effects as men do at lower levels of use, with some evidence that women modulate cannabis use during simultaneous use episodes to avoid greater subjective intoxication. Finally, women appear more vulnerable to experiencing a range of positive and negative consequences from SAC relative to men.

Summary

Research has identified several important sex/gender differences in SAC and its correlates and consequences. However, research has primarily focused on white and cisgender populations, with a need for more research among racial/ethnic and gender minorities.

Dynamic relations among simultaneous alcohol and cannabis use, subjective responses, and problem drinking during naturally occurring drinking episodes

BACKGROUND

Simultaneous alcohol and cannabis use (SAM) is associated with riskier drinking. However, little is known regarding mechanisms of risk during drinking episodes. The current study tested whether subjective responses to simultaneous vs. alcohol-only use (i.e., high arousal positive/reward, high arousal negative/aggression, low arousal positive/relaxation, low arousal negative/impairment) were mechanisms through which SAM use was associated with daily drinking.

METHODS

Emerging adults who co-use alcohol and cannabis (N=85) completed 21 days of ecological momentary assessment with drink-contingent reports during drinking episodes. Participants reported on their simultaneous use and current subjective effects during drink reports and past-night total drinks consumed and negative consequences experienced the next morning. Three-level multilevel models (momentary, daily, person level) tested whether SAM use predicted subjective responses, and whether subjective responses mediated associations between SAM use, heavier drinking and negative consequences.

RESULTS

At the momentary and day-level, SAM (vs. alcohol-only) use predicted increased high arousal positive/rewarding, low arousal positive/relaxing, and low arousal negative/impairing subjective effects. SAM use indirectly predicted heavier day-level drinking and further negative consequences through high arousal positive/rewarding response. SAM use also indirectly predicted day-level negative consequences through low arousal negative/impairing response. At the person-level, more frequent SAM use predicted higher person-average high arousal positive/rewarding and low arousal positive/relaxing responses, and high arousal positive/rewarding response mediated relation between SAM frequency and heavier drinking.

CONCLUSIONS

Simultaneous use was associated with reward, relief, and impairment, and reward and impairment were mechanisms of risk between SAM use and riskier drinking. Findings may inform theory and just-in-time interventions seeking to reduce alcohol misuse.

Cannabis Recreational Legalization and Prevalence of Simultaneous Cannabis and Alcohol Use in the United States

BACKGROUND

Simultaneous cannabis/alcohol use, using both substances within a short time interval so that their effects overlap, has a greater risk of potential negative consequences than single-substance use and is more common in younger age. Relationships between recreational cannabis laws (RCLs) and changes in simultaneous cannabis/alcohol use prevalence remain untested.

OBJECTIVE

To examine trends in simultaneous cannabis/alcohol use from 2008 to 2019, and investigate associations between implementation of RCLs (i.e., presence of active legal dispensaries or legal home cultivation) and simultaneous cannabis/alcohol use in the United States (U.S.).

DESIGN

Repeated cross-sectional samples from the 2008-2019 U.S. National Survey on Drug Use and Health (NSDUH).

PARTICIPANTS

Respondents (51% female) aged 12 and older.

INTERVENTIONS

Changes in simultaneous cannabis/alcohol use before and after RCL implementation (controlling for medical cannabis law implementation) were compared in different age groups (12-20, 21-30, 31-40, 41-50, 51+), using adjusted multi-level logistic regression with state random intercepts and an RCL/age group interaction.

MEASUREMENTS

Self-reported simultaneous cannabis/alcohol use.

RESULTS

From 2008 to 2019, the overall prevalence of simultaneous cannabis/alcohol use declined among those aged 12-20 but increased in adults aged 21+. Model-based simultaneous cannabis/alcohol use prevalence increased after RCL implementation among respondents aged 21-30 years (+1.2%; aOR= 1.15 [95%CI = 1.04-1.27]), 31-40 years (+1.0; 1.15 [1.04-1.27]), and 41-50 years (+1.75; 1.63 [1.34-1.98]), but not in individuals aged <21 or 51+ years.

CONCLUSIONS

Implementation of recreational cannabis policies resulted in increased simultaneous use of cannabis and alcohol, supporting the complementarity hypothesis, but only among adults aged 21+. Efforts to minimize harms related to simultaneous cannabis/alcohol use are critical, especially in states with RCLs. Future studies should investigate cultural norms, perceived harm, and motives related to simultaneous use.

Current Cannabidiol Safety: A Review

BACKGROUND

Marijuana, also known as cannabis, is the second most widely used illegal psychoactive substance smoked worldwide after tobacco, mainly due to the psychoactive effects induced by D-9-tetrahydrocannabinol (9-THC). Cannabidiol (CBD) is extracted from cannabis and may be used as an anti-inflammatory agent. Some patents on cannabidiol are discussed in this review. The cannabinoid is a non-psychoactive isomer of the more infamous tetrahydrocannabinol (THC); and is available in several administration modes, most known as CBD oil.

OBJECTIVES

This study aims to provide an enhanced review of cannabidiol properties used in treating inflammation. This review also emphasises the current safety profile of cannabidiol.

METHODS

Cannabis is also called Marijuana. It is the second most commonly used illegal psychoactive substance in the universe after tobacco. D-9-tetrahydrocannabinol (9-THC) present in cannabis produces psychoactive effects. Cannabidiol (CBD) extracted from cannabis is used for antiinflammatory purposes. Cannabis smoking causes various types of cancer, such as lung, tongue, and jaw. The current review took literature from Google Scholar, PubMed, and Google Patents. Many clinical investigations are included in this review.

RESULT

After analysing the literature on cannabis, it has been suggested that although cannabis is banned in some countries, it may be included in the treatment and mitigation of some diseases and symptoms like pain management, epilepsy, cancer, and anxiety disorder. Mild side effects were frequently observed in cannabis medications, which included infertility in females, liver damage, etc. Conclusion: Cannabis contains chemical compounds such as the cannabinoids delta-9- tetrahydrocannabinol (THC), a psychoactive substance, and non-psychoactive cannabidiol (CBD). Cannabidiol has been confirmed as an efficient treatment of epilepsy in several clinical trials, with one pure CBD product named Epidiolex. It is also used in treating anxiety and acne, as a pain reliever, and has anti-inflammatory properties.

Protocol for a mobile laboratory study of co-administration of cannabis concentrates with a standard alcohol dose in humans

Cannabis is commonly used among people who drink alcohol, yet evidence on acute effects of co-use is conflicting. Two important variables that may influence the effects of cannabis and alcohol are cannabinoid content (i.e., the ratio of cannabidiol [CBD] and 9-tetrahydrocannabinol [THC]) as well as the order of use (i.e., cannabis before alcohol vs. alcohol before cannabis). Research is mixed regarding the acute imapct of cannabis on alcohol consumption and intoxication, with some studies suggesting additive effects of alcohol and cannabis, and others demonstrating negligible effects of combining these substances. Further complicating this, high-THC-content cannabis concentrates are increasingly popular on the legal-market, but to our knowledge, no studies have explored concentrate and alcohol co-use. In addition to cannabinoid content, order of use may influence intoxication and other acute effects, but is also understudied. Co-use studies typically administer a fixed dose of alcohol before cannabis, and there is a lack of data on the acute effects of cannabis before alcohol. Thus, there is a need for experimental co-use studies exploring the impact of cannabinoid content (particularly of highly potent cannabis concentrates) and order effects on intoxication. This study uses a federally-compliant mobile laboratory procedure to explore the effects of co-administration of legal-market cannabis concentrates with a moderate alcohol dose (.8g/kg) in a sample of community participants who regularly use alcohol and cannabis. The study will also explore alcohol and cannabis order effects (cannabis before alcohol vs. alcohol before cannabis). Outcomes are objective intoxication (measured using blood cannabinoid level, heart rate, psychomotor performance and breath alcohol level [BrAC]) and subjective intoxication (assessed via self-report measures). Overall, this study may influence harm-reduction recommendations for individuals who drink alcohol and use cannabis.

Indirect and direct effects of simultaneous alcohol and cannabis use on alcohol hangovers

INTRODUCTION

Simultaneous use of alcohol and cannabis (i.e., using both on same occasion) is a risk factor for heavier drinking and negative alcohol consequences; however, little research has investigated risk conferred for specific negative consequences. One theoretically relevant negative consequence may be alcohol hangovers; however, no studies have tested cross-sectional or prospective relations between simultaneous use and experiencing alcohol hangovers.

METHOD

The current study (N = 2,964) used public-access data from the National Longitudinal Study on Adolescent to Adult Health (Add Health) to test whether simultaneous alcohol and cannabis use conferred risk for hangover frequency directly or indirectly through heavier drinking. The current study also tested moderated mediation by depressive symptoms, considering simultaneous users have higher levels of depressive symptoms, and depressive symptoms largely mirror those of a hangover.

RESULTS

In a cross-sectional model, simultaneous use was associated with more frequent hangovers both directly and indirectly through heavier drinking. In a prospective model, simultaneous use indirectly predicted more frequent hangovers through heavier drinking; however, the direct path was not significant. None of the paths from simultaneous use to drinking or hangovers were moderated by depressive symptoms in either model.

CONCLUSIONS

The current study suggests that, both concurrently and prospectively, heavier drinking explained significant variance in the relation between simultaneous use and hangover frequency. The significant direct effect of simultaneous use in the cross-sectional model suggests that simultaneous users may have individual characteristics, outside of depressive symptoms, that confer risk for more frequent hangovers above and beyond heavier drinking.

Temporal trends in alcohol, cannabis, and simultaneous use among 12th-grade U.S. adolescents from 2000 to 2020: Differences by sex, parental education, and race and ethnicity

BACKGROUND

Simultaneous use of alcohol and cannabis to enhance each other's effect can cause potential harm. Time trends are diverging in adolescent use of alcohol, which is declining, and cannabis, which is increasing among certain subgroups. However, little is known about trends in their simultaneous and non-simultaneous use. Racial and socioeconomic disparities are emerging in cannabis use, which may portend consequences to public health.

METHODS

The 2000 to 2020 Monitoring the Future surveys included approximately 38,000 U.S. 12th-grade students with information on simultaneous use and pertinent demographic factors. A 5-level alcohol/cannabis measure included past-year simultaneous use (i.e., alcohol and cannabis use at the same time), non-simultaneous alcohol and cannabis use, alcohol-use-only, cannabis-use-only, and no use. Multinomial logistic regressions estimated associations (adjusted relative risk ratios; aRRR) with time period (2000 to 2004, 2005 to 2009, 2010 to 2014, 2015 to 2020). Models were adjusted and included interactions with sex, race/ethnicity, and parental education.

RESULTS

Between 2000 and 2020, simultaneous alcohol/cannabis use among 12th graders decreased from 24.4% to 18.7%. From 2015 to 2020 compared to 2000 to 2004, the odds of simultaneous use (adjusted relative risk ratio (aRRR) vs. no use = 0.57, 95% CI [0.50, 0.66]) and alcohol-use-only (aRRR = 0.55, 95% CI [0.49, 0.61]) decreased, while cannabis-use-only odds increased (aRRR = 2.59, 95% CI [1.87, 3.59]). Notably, the prevalence of cannabis-use-only more than doubled from 2011 to 2019. The odds of simultaneous use, alcohol-use-only, and non-simultaneous use of alcohol and cannabis declined more rapidly among males than females, whereas the odds for cannabis-use-only increased faster for females than males. Increases in cannabis-use-only were faster for non-white adolescents.

CONCLUSION

Simultaneous use of alcohol and cannabis is declining among U.S. adolescents, but the decline is slower among females than males. Declines in simultaneous use are largely concomitant with historical declines in alcohol use, indicating that a continued focus on reducing alcohol use among adolescents and young adults has extended benefits to other adolescent substance use. However, cannabis use without any reported past-year alcohol use more than doubled in the last decade, a concerning trend.

Combined alcohol and cannabinoid exposure leads to synergistic toxicity by affecting cerebellar Purkinje cells

Combined use of cannabis and alcohol results in greater psychoactive toxicity than either substance alone, but the underlying central mechanisms behind this worsened outcome remain unclear. Here we show that the synergistic effect of Δ⁹-tetrahydrocannabinol (THC) and ethanol on motor incoordination in mice is achieved by activating presynaptic type 1 cannabinoid receptors (CB₁R) and potentiating extrasynaptic glycine receptors (GlyR) within cerebellar Purkinje cells (PCs). The combination of ethanol and THC significantly reduces miniature excitatory postsynaptic current frequency in a CB₁R-dependent manner, while increasing the extrasynaptic GlyR-mediated chronic chloride current, both leading to decreased PC activity. Ethanol enhances THC actions by boosting the blood-brain-barrier permeability of THC and enriching THC in the cell membrane. Di-desoxy-THC, a designed compound that specifically disrupts THC-GlyR interaction without affecting the basic functions of CB₁R and GlyR, is able to restore PC function and motor coordination in mice. Our findings provide potential therapeutic strategies for overcoming the synergistic toxicity caused by combining cannabis and alcohol use.

Cannabis use and subjective response to alcohol in the human laboratory

BACKGROUND

Cannabis is often used in combination with alcohol; yet, whether cannabis use impacts risk factors for alcohol use disorder (AUD) remains unknown. Subjective response (SR) to alcohol represents a biobehavioral risk factor for subsequent heavy drinking and for developing AUD. Given the high prevalence of alcohol and cannabis co-use, it is plausible to hypothesize that cannabis users differ in SR to alcohol compared to non-cannabis users. The purpose of this study is to examine the influence of past-month cannabis use on subjective response to alcohol in the human laboratory.

METHODS

This study culled data from multiple alcohol administration trials to test whether cannabis users, compared to non-cannabis users, differed in subjective response to alcohol, comprised of four domains: stimulation, sedation, negative affect, and craving. Non-treatment-seeking heavy drinkers (N = 168) completed a battery of self-report scales of mood and alcohol/cigarette/cannabis use and problems. All participants completed an intravenous alcohol administration session wherein SR domains were measured at the following breath alcohol concentrations (BrAC): baseline (i.e., 0), 20, 40, and 60 mg%.

RESULTS

Multilevel statistical analyses revealed that cannabis users had a greater reduction in negative affect during alcohol administration, compared to non-cannabis users. No significant differences were found for the other SR domains.

CONCLUSIONS

Using a large sample and advanced data analytic methods, this study extends the literature by suggesting that cannabis users are more sensitive to alcohol-induced reductions in negative affect compared to non-cannabis users. This work extends research on how cannabis use may influence risk factors for AUD, such as subjective response to alcohol.

Effects of Δ9-Tetrahydrocannibinol (THC) on Obesity at Different Stages of Life: A Literature Review

The Cannabis sativa plant has historically been used for both recreational and medical purposes. With the recent surge in recreational use of cannabis among adolescents and adults in particular, there is an increased obligation to determine the short- and long-term effects that consuming this plant may have on several aspects of the human psyche and body. The goal of this article was to examine the negative effects of obesity, and how the use of Δ9-tetrahydrocannibinol (THC) or cannabidiol (CBD) can impact rates of this global pandemic at different timepoints of life. Conflicting studies have been reported between adult and adolescents, as there are reports of THC use leading to increased weight due to elevated appetite and consumption of food, while others observed a decrease in overall body weight due to the regulation of omega-6/omega-3 endocannabinoid precursors and a decrease in energy expenditure. Studies supported a positive correlation between prenatal cannabis use and obesity rates in the children as they matured. The data did not indicate a direct connection between prenatal THC levels in cannabis and obesity rates, but that this development may occur due to prenatal THC consumption leading to low birthweight, and subsequent obesity. There are few studies using animal models that directly measure the effects that prenatal THC administration on obesity risks among offspring. Thus, this is a critical area for future studies using a developmental framework to examine potential changes in risk across development.

Patterns of Cannabis and Alcohol Co-Use: Substitution Versus Complementary Effects

PURPOSE

The purpose of this review is to discuss the literature regarding the concurrent use (co-use) of alcohol and cannabis and competing hypotheses as to whether cannabis acts as a substitute for (i.e., replacing the effects of alcohol, resulting in decreased use) or a complement to (i.e., used to enhance the effects of alcohol, resulting in increased use) alcohol. The impact of cannabis use on alcohol-related outcomes has received increased attention in the wake of ongoing legalization of cannabis for both medical and recreational purposes. Evidence for both hypotheses exists in the literature across a broad range of data collection methods and samples and is carefully reviewed here. In addition, various mechanisms by which cannabis may act as an alcohol substitute or complement are explored in depth with the goal of better understanding equivocal findings.

SEARCH METHODS

This review includes articles that were identified from a search for studies on alcohol and cannabis co-use, with a specific focus on studies exploring complementary versus substitution aspects of co-use. Search terms were included in Google Scholar, PsycINFO, MEDLINE, and Web of Science. Eligible studies were those that measured alcohol and cannabis co-use in human samples in laboratory, survey, or ecological momentary assessment studies, or that directly referenced substitution or complementary patterns of use.

SEARCH RESULTS

Search results returned 650 articles, with 95 meeting inclusion criteria.

DISCUSSION AND CONCLUSIONS

Results of this review reveal compelling evidence for both substitution and complementary effects, suggesting nuanced yet significant distinctions across different populations examined in these studies. Several mechanisms for the impact of cannabis use on alcohol-related outcomes are identified, including patterns and context of co-use, timing and order of use, cannabinoid formulation, pharmacokinetic interactions, and user characteristics (including diagnostic status), all of which may influence substitution versus complementary effects. This review will inform future research studies examining this topic in both clinical and community samples and aid in the development of treatment and prevention efforts targeting those populations most vulnerable to negative consequences of co-use. Finally, this review highlights the need for additional research in more diverse samples and the use of mixed-methods designs to examine both pharmacological and contextual influences on co-use.

Exploring the Association of e-Cigarette and/or Cannabis Use with Heavy Episodic Drinking among Ontario Adults

Background: The use of electronic cigarettes and cannabis has significantly increased in recent years, which raises public health concerns. There are also concerns about the association of these substances with drinking behaviors. The main objective of the present study is to examine the association of e-cigarettes and/or cannabis use with heavy episodic drinking (HED) among Ontario adults. Methods: The sample consisted of 5,564 adults from the Monitor Survey in 2018 and 2019. Cannabis and e-cigarette use reflected any use of the substances in the past 12 months. HED was defined as consumption of four/five or more drinks on a single occasion at least monthly in the past 12 months. Odds ratios (OR) were estimated from logistic regression models accounting for complex survey design and sociodemographic factors. Results: Overall, the prevalence of HED was 17.5% in 2018 and 2019. Among participants who reported both e-cigarette and cannabis use, about one-half (50.4%) reported HED at least monthly. Adjusting for covariates, the odds of HED were 5.71 (95%CI, 3.92-8.30) times higher among those who reported both e-cigarette and cannabis use compared to those who used neither substance. Conclusions: The use of e-cigarettes and cannabis are significantly associated with heavy episodic drinking among adults, indicating that those who engage in the dual use of e-cigarette and cannabis may be an important group to target with intervention programs.

Assessing subjective cannabis effects in daily life with contemporary young adult language

INTRODUCTION

Subjective ratings of cannabis effects are important predictors of use-related consequences. However, psychometric research is fairly limited, particularly for measures to capture variability in daily life when diverse modes of cannabis administration and co-substance use are common.

METHODS

This study evaluated the predictive utility of a revised item to assess perceived cannabis effects and examined modes of cannabis administration and alcohol and nicotine co-use as moderators. Participants were 106 young adults (18-25 years; 51% female) who completed up to 14 consecutive daily reports of substance use (n = 1405 person-days). Two measures of subjective effects were examined: a standard item (0-100 rating of "how high do you feel?") and a revised item that uses four crowd-sourced anchor points ranging from relaxed (0), calm/chill (33), high (67), and stoned/baked (100). The items shared substantial variance (Pseudo-R² = 59.5%), however, the revised item showed greater within-person variability (77.0% vs. 68.8%) and stronger day-level associations with consumption levels (Pseudo-R² = 25.0% vs. 16.7%).

RESULTS

The cannabis consumption-subjective effects link was weaker on blunt-only days compared to vape-only days. Subjective cannabis effects were higher on nicotine co-use days after controlling for cannabis consumption; neither alcohol nor nicotine co-use moderated the cannabis consumption-subjective effects link.

DISCUSSION

The revised subjective cannabis effects item is a viable alternative to the standard item among young adults who engage in simultaneous alcohol and cannabis use.

CONCLUSIONS

Future research focused on characterizing the variability in cannabis effects is needed.

Changes in alcohol use by cannabis use status among adolescents and young adults in the United States: Emerging evidence for both substitution and complementarity

BACKGROUND

The majority of adolescents and young adults (AYA) who use cannabis also use alcohol. Although cannabis use is increasing in the United States (US), it is not known whether the increase contributes to either increased co-use of alcohol and cannabis (e.g., complementarity) or replacement of alcohol with cannabis (e.g., substitution). The current study estimated the prevalence of alcohol use by cannabis use status among US AYA ages 12 to 25 in 2018 and trends in alcohol use by cannabis use status from 2002 to 2018.

METHODS

Data were drawn from the 2002 to 2018 National Survey on Drug Use and Health public use data files. The analytic sample included AYA ages 12 to 25 (2018 sample, n = 26,924; total combined sample 2002 to 2018, n = 576,053). Linear and logistic regression models were used to estimate past-month alcohol use, daily alcohol use, and average quantity of alcohol consumed among AYA with and without past-month cannabis use from 2002 to 2018.

RESULTS

In 2018, any alcohol use and daily alcohol use were significantly more common among AYA who used cannabis use than those who did not use cannabis. Overall, any alcohol use, daily alcohol use, and average drinks per day declined from 2002 to 2018 among AYA irrespective of recent cannabis use. However, the decline in any alcohol use, daily alcohol use, and average alcohol drinks per day was more rapid among AYA who used cannabis (daily and nondaily) than those who did not use cannabis. The rate of decline in average alcohol drinks per day was also higher among AYA with daily compared to nondaily cannabis use.

CONCLUSIONS

Even with declines in alcohol use over time, drinking is much more common among AYA who report cannabis than those without recent cannabis use, which is consistent with complementarity. Yet, because the decline in alcohol use has been more rapid among AYA who use cannabis, there is also evidence of substitution. Thus, the current data on alcohol and cannabis use are consistent with both complementarity and substitution. However, these relationships may change as cannabis legalization expands over time.

Cannabis and Alcohol Use and Their Associations with Sleep: A Daily Diary Investigation of Single-Use and Co-Use in College Students

Introduction: Sleep continuity problems are widespread among college students and may be influenced by single-use and co-use of alcohol and cannabis. We examined the within-person associations of alcohol and cannabis use with subsequent sleep experiences in the everyday life of college students. Materials and Methods: A sample of 80 college students reported prior-night alcohol and cannabis use and sleep experiences for 14 consecutive days. Mixed-effects models examined the within-person relationships between alcohol and cannabis use (single- and co-use) and subsequent (1) sleep-onset latency, (2) total sleep time, (3) number of awakenings, and (4) early awakenings that night. Results: Compared to no-use evenings, alcohol and cannabis, used separately or together (co-use), were associated with shorter sleep-onset latency and longer total sleep time. Students reported more nightly awakenings after alcohol-only use compared to no-use and after co-use, and they reported fewer early awakenings after no-use and co-use. Conclusions: In line with previous experimental findings, we found that alcohol and cannabis use in the everyday life of college students were associated with sleep-inducing effects, and that alcohol use was associated with disturbed sleep continuity. The results suggest that cannabis may curb alcohol's detrimental effect on the number of awakenings and may reduce the incidence of early awakenings. Yet, due to lack of control for potentially important confounders (e.g., quantity of cannabis/alcohol consumed, withdrawal) the current results may be best seen as preliminary and further research is needed before causal inferences can be reached.

Associations between simultaneous alcohol and cannabis use and next-day negative affect among young adults: The role of sex and trait anxiety

BACKGROUND AND AIMS

The simultaneous use of alcohol and cannabis ("simultaneous alcohol and marijuana [SAM] use") is common among young adults and associated with negative substance-related consequences. SAM use may be tied to fluctuating mood states such as negative affect and individual characteristics including trait level of anxiety and sex. However, little is understood about their collective role. In this study, we sought to understand the daily link between SAM use and negative affect and whether this link might differ by both trait anxiety and sex.

METHOD

Participants were 154 young adults (57.8% female, 72.7% White, M age = 20.2) who completed baseline surveys on trait anxiety symptoms and up to 14 consecutive daily surveys on their substance use and affective states.

RESULTS

Multilevel models tested for associations of type of substance use day (i.e., alcohol-only days, cannabis-only days, and no use days relative to SAM use days) with next-day negative affect. Three-way and lower order interactions were tested for substance use day type, anxiety, and sex. Two three-way interactions between cannabis-only days, anxiety, and sex and between alcohol-only days, anxiety, and sex emerged such that SAM use was associated with greater next-day negative affect relative to single substance use days particularly among female participants with elevated anxiety.

CONCLUSIONS

Anxiety and sex are salient factors in the link between SAM use relative to single-substance use and daily negative affect. Study findings reinforce the need to account for all of these factors in order to develop maximally efficacious substance use interventions.

Alcohol-medication interactions: A systematic review and meta-analysis of placebo-controlled trials

Alcohol and other xenobiotics may limit the therapeutic effects of medications. We aimed at investigating alcohol-medication interactions (AMI) after the exclusion of confounding effects related to other xenobiotics. We performed a systematic review and meta-analysis of controlled studies comparing the effects induced by alcohol versus placebo on pharmacodynamic and/or pharmacokinetic parameters of approved medications. Certainty in the evidence of AMI was assessed when at least 3 independent studies and at least 200 participants were available. We included 107 articles (3097 participants): for diazepam, cannabis, opioids, and methylphenidate, we found significant AMI and enough data to assign the certainty of evidence. Alcohol consumption significantly increases the peak plasma concentration of diazepam (low certainty; almost 290 participants), cannabis (high certainty; almost 650 participants), opioids (low certainty; 560 participants), and methylphenidate (moderate certainty; 290 participants). For most medications, we found some AMI but not enough data to assign them the certainty grades; for some medications, we found no differences between alcohol and placebo in any outcomes evaluated. Our results add further evidence for interactions between alcohol and certain medications after the exclusion of confounding effects related to other xenobiotics. Physicians should advise patients who use these specific medications to avoid alcohol consumption. Further studies with appropriate control groups, enough female participants to investigate sex differences, and elderly population are needed to expand our knowledge in this field. Short phrases suitable for indexing terms.

Combined use of alcohol and cannabis: Introduction to the special issue

OBJECTIVE

Combined use of alcohol and cannabis has increased in recent years among certain age groups, and it is well established that individuals who use both alcohol and cannabis (especially if they use both at the same time) are at increased risk for substance-related harms relative to individuals who use only one substance. Far less attention has been placed on the patterns, predictors, and psychological processes associated with alcohol and cannabis co-use, which may inform prevention and intervention programming. Accordingly, this special issue was assembled to advance our understanding of the characteristics and consequences of combined use of alcohol and cannabis.

METHOD

In this introductory article, the Guest Editors present the background for this work and provide an overview of the 14 articles that comprise this special issue.

RESULTS

Studies contained in this special issue capitalize on a variety of methodologies, with a particular focus on investigating typologies of alcohol and cannabis co-use, clarifying motivational and social contexts of co-use, and tracking co-use in daily life via daily diary and ecological momentary assessment designs. Experimental and neuroimaging examinations of co-use are also included. Collectively, the studies generally provide evidence that combined use of alcohol and cannabis is associated with unique characteristics, predictors, consequences, and psychological processes relative to single-substance use.

CONCLUSIONS

The studies in this special issue provide new insight into combined use of alcohol and cannabis. They also highlight a number of promising avenues for future inquiry as the literature on alcohol and cannabis co-use continues to grow. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Alcohol, marijuana, and nicotine use as predictors of impaired driving and riding with an impaired driver among college students who engage in polysubstance use

OBJECTIVE

While alcohol, marijuana, and nicotine are the most commonly used substances, there is limited research on the between- and within-person associations of their use and driving under the influence (DUI) and riding with an impaired driver (RWID). The current study utilized a burst design to assess how use and co-use of these substances is associated with DUI and RWID.

METHODS

College student drinkers with past-year marijuana and/or nicotine use (N = 367) were assessed on two consecutive weekends for three semesters. Logistic regression compared students who only reported drinking to student drinkers who used marijuana, nicotine, or all three substances on likelihood to DUI and RWID. Multilevel logistic models assessed the associations of varied combinations of substances with the daily likelihood of DUI and RWID.

RESULTS

Compared to students who only used alcohol, students who also reported marijuana use were more likely to DUI (OR = 5.44), and students who reported use of alcohol, nicotine and marijuana more likely to DUI (OR = 10.33) and RWID (OR = 10.22). Compared to occasions when only alcohol was used, DUI was more likely on marijuana only occasions (OR = 9.08), and RWID was more likely on alcohol and marijuana occasions (OR = 3.86). However, confidence intervals were wide for effects.

DISCUSSION

Students reporting use of all 3 substances had higher overall risk of DUI and RWID indicating prevention efforts for DUI and RWID should include all substances. Implications for prevention and intervention strategies at the individual and environmental level are discussed.

Qualitative examination of simultaneous alcohol and cannabis use reasons, evaluations, and patterns among heavy drinking young adults

Use of alcohol and cannabis together so their effects overlap (simultaneous use) is common among college students and associated with numerous negative consequences. The aim of this study was to gain insight into college students' recent simultaneous use events in order to inform future studies (i.e., generate hypotheses, inform measures/assessments of simultaneous use, and identify factors influencing simultaneous use). Qualitative interviews of simultaneous use experiences among heavy drinking college students (n = 38) were conducted to better understand reasons for simultaneous use, evaluations of simultaneous use events, and patterns of substance use during simultaneous use events. Findings indicated that students' reasons for simultaneous use included traditional four-factor motive types (i.e., social, conformity, enhancement, and coping), cross-fading motives, harm reduction motives (e.g., to drink less), and reactive/situational reasons (e.g., because it was offered/available). There was variability in participants' subjective evaluations of how positive versus negative simultaneous use events were and how this compared to single-substance events. Evaluation of simultaneous use events depended on patterns of use, external and internal context, and consequences experienced. Additionally, patterns of simultaneous use including order of substances, timing of using each substance, and quantities of substances used were highly variable across participants. Notably, participants endorsed patterns of use they perceived to reduce negative consequences during simultaneous use events. Further research on reasons for simultaneous use and patterns of use may help identify simultaneous use occasions that result in greater risk; identification of high-risk simultaneous use occasions and evaluation of these occasions can then help inform targeted interventions. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Impact of co-ingestion of ethanol on the clinical symptomatology and severity of patients attended in the emergency department for recreational drug toxicity

OBJECTIVE

Investigate whether there are differences in the drugs involved, symptomatology and severity of drug intoxication in patients with co-ingestion of alcohol attended in hospital emergency departments (ED).

METHOD

Patients attended in 11 Spanish EDs due to drug intoxication were included. Sociodemographic and clinical characteristics were collected. A combined adverse event of cardiorespiratory arrest, need for intubation, and admission to intensive care or death was considered as the primary indicator of severity. The symptomatology and severity were compared adjusted for age, sex and type of drug based on whether or not ethanol had been co-ingested.

RESULTS

3925 patients (alcohol co-ingestion: 2290, 58.3%) with a mean age of 33 (±11) years were included, and 25% were women. Co-ingestion of alcohol was observed in younger patients, in EDs in areas with high leisure tourism, on holidays and during the early morning hours. It was also more frequent in individuals intoxicated by amphetamine derivatives (66.2%) and cocaine (65.7%), and was more frequently associated with a reduction in consciousness (odds ratio [OR] = 2.13, 95% confidence interval [CI] 1.69-2.67) and agitation/aggressiveness (OR = 1.22, 95% = 1.04-1.43). A combined adverse event was observed in 114 patients (2.9%) with no differences between individuals co-ingesting or not ethanol (3.1% vs. 2.7%; OR = 1.11, 95% CI = 0.74-1.65).

CONCLUSION

Co-ingestion of alcohol is more frequent in individuals intoxicated by cocaine and amphetamines and predisposes a greater reduction in the level of consciousness or agitation, although there are no differences in the severity of the episodes of drug intoxication.

Daily-level effects of alcohol, marijuana, and simultaneous use on young adults' perceived sleep health

STUDY OBJECTIVES

Simultaneous alcohol and marijuana (SAM) use is increasingly prevalent among young adults but has adverse health consequences. The current study examined daily-level associations between perceived sleep health and SAM use, relative to non-substance-use days and alcohol- or marijuana-only days. We also estimated linear associations between alcohol/marijuana use and perceived sleep health and explored whether effects were moderated by combined use of alcohol and marijuana.

METHODS

A community sample of SAM-using young adults (N=409; Mage=21.61, SD=2.17; 50.9% female; 48.2% White; 48.9% college students) completed twice-daily surveys for five 14-day sampling bursts. Daily measurements assessed substance use and perceived sleep health in terms of subjective sleep quality, negative impact of sleep on functioning, and symptoms of insomnia.

RESULTS

Multilevel models indicated that, relative to non-substance-use days, participants reported poorer perceived sleep health on alcohol-only days, better perceived sleep health on marijuana-only days, and mixed evidence regarding SAM use (i.e., fewer perceived symptoms of insomnia, but poorer perceived next day functioning attributed to sleep). Daily-level estimates showed increased alcohol use was associated with poorer perceived sleep health, while stronger effects from marijuana were associated with better perceived sleep health. Across all indices of sleep health, only one linear association was moderated by combined use: The adverse association between alcohol and next day functioning was weaker on days alcohol was combined with marijuana.

CONCLUSIONS

Findings provide additional evidence for daily-level effects of alcohol and marijuana use on perceived sleep health and address an important literature gap regarding potential adverse effects of SAM use.

Ordering in alcohol and cannabis co-use: Impact on daily consumption and consequences

BACKGROUND

Co-use of alcohol and cannabis is highly prevalent among young adults and college students. Between-person reports suggest that co-use is associated with the experience of more frequent consumption and related consequences, compared to single substance use. However, recent studies have found conflicting evidence regarding the impact of co-use use on consumption and consequences in daily or event-level investigations. Conflicting evidence may be due to understudied factors, such as the order in which alcohol and cannabis are used. The current study aimed to examine the effect of substance use order on a) alcohol consumption; b) cannabis consumption; and c) negative alcohol and cannabis consequences.

METHODS

Data were collected from U.S. undergraduate college student alcohol and cannabis users (N = 258) who completed two 28-day longitudinal online assessment bursts examining alcohol and cannabis co-use patterns. Data were collected five times per day during both bursts (three months apart).

RESULTS

Controlling for between-person alcohol and cannabis use, within-person mixed-effects models indicated that using cannabis first within a co-use day was associated with lower daily alcohol consumption, but greater daily cannabis consumption. Substance use ordering was not linked to consequences, whereas between-person levels of alcohol consumption and within-person number of drinks in a day were positive predictors of consequences.

CONCLUSIONS

Overall, results highlighted that order of substance use is a robust predictor of consumption on co-use days. Therefore, future research on co-use use should consider patterns of use in addition to level of use.

Impact of state-level cannabis legalization on poly use of alcohol and cannabis in the United States, 2004-2017

BACKGROUND

Cannabis policy has shifted toward legalization in many parts of the United States (US). While attention has been focused on whether legalization will lead to changes in cannabis use, it is conceivable that legalization will also affect use of substances that individuals frequently use with cannabis. This study assessed whether cannabis legalization impacted the prevalence of poly use of cannabis and alcohol from 2004 to 2017 and estimated the prevalence of cannabis and alcohol poly use in 2017.

METHODS

Public and restricted-use data from the US 2004-2017 National Survey on Drug Use and Health were analyzed. Data on past-month cannabis and alcohol use were assessed each year. Cannabis legalization was determined by the presence or absence of medical marijuana laws (MML) and recreational marijuana laws (RML) in each state. Difference-in-difference approach was used to estimate the association of MML and RML on cannabis and alcohol use overall and by sociodemographic subgroups (e.g., age, income, education).

RESULTS

Between 2004 and 2017, poly use of cannabis and alcohol increased while alcohol-only use decreased. MML were associated with increases in poly use only among adults over age 50 and among those with higher annual incomes and higher education, while RML were associated with increases in poly use broadly among adults across sociodemographic groups.

CONCLUSIONS

Legalization of cannabis was associated with increases in cannabis-alcohol poly use in the US. RML were associated with increases across demographics, while the impact of MML was more limited to certain sociodemographic groups.

Does the Combination Matter? Examining the Influence of Alcohol and Cannabis Product Combinations on Simultaneous Use and Consequences in Daily Life

BACKGROUND

Alcohol and marijuana/cannabis are frequently used simultaneously (i.e., SAM use). SAM use is complex, and the ways in which alcohol and cannabis are simultaneously used may reveal differential effects. The purpose of this study was to examine day-level effects of distinct alcohol and cannabis product combinations on simultaneous use and consequences on that day.

METHODS

College student SAM users (N = 274; 50% women; Mage  = 19.82 years) were recruited to complete 54 days of data collection, including 5 repeated daily surveys each day. We identified 12 distinct product combinations reported during SAM-use days. We tested 4 reference groups, with one reflecting the most common use pattern and 3 potentially risky use patterns. We considered 3 outcomes (negative consequences, number of drinks, and number of cannabis uses) and used generalized linear mixed-effects models disentangling within- from between-person effects in all analyses.

RESULTS

Using multiple products (≥2) of alcohol was consistently linked to higher odds of experiencing a negative consequence. Combining beer with only one cannabis product (leaf or concentrate) was consistently associated with lower odds of a consequence. Combining cannabis with multiple alcohol products was associated with heavier alcohol consumption. Using dual cannabis products also was associated with heavier cannabis consumption, but this pattern was not significantly different than using concentrate only on a given day.

CONCLUSION

This is the first study to examine day-level influences of distinct alcohol and cannabis product combinations on consumption and consequences among young adult SAM users. Findings suggest that mixing alcohol products confers greater risk for negative consequences and heavier consumption, whereas there is little difference in cannabis consumption when using concentrate only vs. 2 cannabis products on a given day, except for concentrate + beer. Our findings support existing protective strategies of not mixing alcohol products and avoiding use of cannabis concentrate for SAM use as well.

Combined vapor exposure to THC and alcohol in pregnant rats: Maternal outcomes and pharmacokinetic effects

Cannabis is the most frequently used illicit drug among pregnant women, yet the potential consequences of prenatal cannabis exposure on development are not well understood. Electronic cigarettes have become an increasingly popular route of administration among pregnant women, in part to user's perception that e-cigarettes are a safer route for consuming cannabis products. Importantly, half of pregnant women who consume cannabis also report consuming alcohol, but research investigating co-consumption of these drugs is limited, particularly with current routes of administration. The purpose of this study was to establish a co-exposure vapor inhalation model of alcohol and THC in pregnant rats, to ultimately determine the effects on fetal development. Pregnant Sprague-Dawley rats were exposed to moderate doses of THC via e-cigarettes, alcohol, the combination, or vehicle daily from gestational days 5-20. Importantly, pharmacokinetic interactions of alcohol and THC were observed during pregnancy. Combined exposure consistently increased blood alcohol concentrations, indicating that THC alters alcohol metabolism. In addition, THC levels also increased over the course of pregnancy and THC metabolism was altered by alcohol. Alcohol, but not THC, exposure during pregnancy reduced maternal weight gain, despite no group differences in food intake. Neither prenatal alcohol nor THC exposure altered gestational length, litter size, sex ratio or birth weight. However, prenatal alcohol exposure delayed eye opening, and prenatal THC exposure decreased body weights during adolescence among offspring. These individual and synergistic effects suggest that this novel co-exposure vapor inhalation paradigm can effectively be used to expose pregnant dams, exerting some effects on fetal development, while avoiding nutritional confounds, birth complications, or changes in litter size. With this model, we have demonstrated that combining THC and alcohol alters drug metabolism, which could have important consequences on prenatal development.

Reductions in alcohol use following medical cannabis initiation: results from a large cross-sectional survey of medical cannabis patients in Canada

BACKGROUND

Evidence details how cannabis can influence the use of other psychoactive substances, including prescription medications, alcohol, tobacco and illicit drugs, but very little research has examined the factors associated with these changes in substance use patterns. This paper explores the self-reported use of cannabis as a substitute for alcohol among a Canadian medical cannabis patient population.

METHODS

Data was derived from a survey of 2102 people enrolled in the Canadian medical cannabis program. We included 973 (44%) respondents who reported using alcohol on at least 10 occasions over a 12 month period prior to initiating medical cannabis, and then used retrospective data on the frequency and amount of alcohol use pre-and post medical cannabis initiation to determine which participant characteristics and other variables were associated with reductions and/or cessation of alcohol use.

RESULTS

Overall, 419 (44%) participants reported decreases in alcohol usage frequency over 30 days, 323 (34%) decreased the number of standard drinks they had per week, and 76 (8%) reported no alcohol use at all in the 30 days prior to the survey. Being below 55 years of age and reporting higher rates of alcohol use in the pre-period were both associated with greater odds of reducing alcohol use, and an intention to use medical cannabis to reduce alcohol consumption was associated with significantly greater odds of both reducing and ceasing alcohol use altogether.

CONCLUSIONS

Our findings suggest that medical cannabis initiation may be associated with self-reported reductions and cessation of alcohol use among medical cannabis patients. Since alcohol is the most prevalent recreational substance in North America, and its use results in significant rates of criminality, morbidity and mortality, these findings may result in improved health outcomes for medical cannabis patients, as well as overall improvements in public health and safety.

Deleterious Effects of Ethanol, Δ(9)-Tetrahydrocannabinol (THC), and Their Combination on the Spatial Memory and Cognitive Flexibility in Adolescent and Adult Male Rats in the Barnes Maze Task

Research demonstrates that adolescents differ from adults in their response to drugs of abuse. The aim of the present study was to examine the influence of ethanol, Δ9-tetrahydrocannabinol hydrochloride (THC), and a combination of these drugs given during adolescence on spatial memory in adolescent and adult rats. Thus, adolescent rats (postnatal day (PND) 30) were subjected to the following groups: 0.9% NaCl; 1.5 g/kg ethanol; 1.0 mg/kg THC; 1.5 g/kg ethanol + 1.0 mg/kg THC. Rats received drug injection four times at three-day intervals. One day after the last injection, half of the treated animals were tested in the Barnes maze task, whereas the remaining animals were tested on PND 70. Results show that there was a significant age effect on spatial memory in the Barnes maze task after these drug administrations. Adolescent animals demonstrated more potent deficits in the spatial learning and memory (probe trial) and in cognitive flexibility (reversal learning) than did adults. However, in adult rats that received these drugs in adolescence, memory decline was observed only after ethanol and ethanol + THC administration. Thus, our results are important in understanding the deleterious impact of THC and/or ethanol abuse during adolescence on memory function across the lifespan (adolescent versus adult).

Alcohol and marijuana co-use: Consequences, subjective intoxication, and the operationalization of simultaneous use

BACKGROUND

Alcohol and marijuana are frequently co-used with overlapping effects. However, the absence of consistent operational definitions delineating simultaneous alcohol and marijuana use (SAM) from concurrent use (CAM) challenges consistent inferences about these behaviors. This study first examined whether daily alcohol and marijuana co-use predicted substance-use related consequences and subjective intoxication; and then evaluated whether competing operationalizations of SAM and CAM were associated with differences in these outcomes on co-use days.

METHODS

A sample of 341 young adult college students who reported past-month use of both alcohol and marijuana "at the same time so that their effects overlapped" completed a two-wave survey with paired 28-day daily experience sampling bursts examining alcohol and marijuana co-use. Outcomes were (a) daily substance-use related consequences; and (b) daily subjective intoxication. Focal predictors were daily drinks and marijuana uses; daily co-use versus single-substance use (Aim 1) or CAM versus SAM (Aim 2); and their interaction.

RESULTS

Participants reported more negative consequences on co-use days versus marijuana-only days and greater subjective intoxication relative to alcohol or marijuana-only days. Competing operationalizations of SAM, defined as daily co-use occurring within 1-240 min in increments of 1 min, found no difference in consequences or subjective intoxication regardless of operationalization.

CONCLUSION

Co-use days involve greater risk than alcohol-only or marijuana-only days. Although there was no evidence of additional daily risk from simultaneous use regardless of the timeframe used to operationalize it, investigating these effects remains challenging due to the generally small timeframe between substances on co-use days in this sample.

One Is Not Enough: Understanding and Modeling Polysubstance Use

Substance use disorder (SUD) is a chronic, relapsing disease with a highly multifaceted pathology that includes (but is not limited to) sensitivity to drug-associated cues, negative affect, and motivation to maintain drug consumption. SUDs are highly prevalent, with 35 million people meeting criteria for SUD. While drug use and addiction are highly studied, most investigations of SUDs examine drug use in isolation, rather than in the more prevalent context of comorbid substance histories. Indeed, 11.3% of individuals diagnosed with a SUD have concurrent alcohol and illicit drug use disorders. Furthermore, having a SUD with one substance increases susceptibility to developing dependence on additional substances. For example, the increased risk of developing heroin dependence is twofold for alcohol misusers, threefold for cannabis users, 15-fold for cocaine users, and 40-fold for prescription misusers. Given the prevalence and risk associated with polysubstance use and current public health crises, examining these disorders through the lens of co-use is essential for translatability and improved treatment efficacy. The escalating economic and social costs and continued rise in drug use has spurred interest in developing preclinical models that effectively model this phenomenon. Here, we review the current state of the field in understanding the behavioral and neural circuitry in the context of co-use with common pairings of alcohol, nicotine, cannabis, and other addictive substances. Moreover, we outline key considerations when developing polysubstance models, including challenges to developing preclinical models to provide insights and improve treatment outcomes.

Setting the baseline: a description of cannabis poisonings at a Canadian pediatric hospital prior to the legalization of recreational cannabis

INTRODUCTION

This study describes the events and circumstances preceding children aged 16 years or younger being treated for cannabis poisoining in the emergency department (ED) of a Canadian pediatric hospital.

METHODS

We extracted cannabis poisoning treated in the ED at British Columbia Children's Hospital (BCCH) between 1 January, 2016 and 31 December, 2018, from the Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP) database. The poisonings were distinguished by the inadvertent or intentional ingestion of cannabis. We reviewed the hospital's electronic health information system and the patients' health records to obtain additional information on the context, including spatial and temporal characteristics.

RESULTS

Of the 911 poisonings treated at BCCH, 114 were related to intentional cannabis use (12.5%). Fewer than 10 poisonings resulted from inadvertent ingestions by children and the median age for these was 3 years. All inadvertent ingestion occurred at home and involved cannabis belonging to the patient's family. The vast majority of poisonings resulted from the intentional use of cannabis only (28.9%) or cannabis use with other psychoactive substances (co-ingestions; 71.1%). The median patient age was 15 years. Most patients reported consuming cannabis through inhalation with peers. Cannabis and co-ingestion poisonings were more often reported on weekdays than weekends. The consumption of cannabis leading to poisoning more often occurred in private residences. Patients with cannabis poisoning more often sought medical treatment themselves or were helped by their family.

CONCLUSION

The characteristics of cannabis poisonings among children are described for the three-year period prior to recreational cannabis legalization in Canada in order to set a baseline for future comparisons. Implications for improving injury prevention initiatives and policies are discussed.

Cross-fading motives for simultaneous alcohol and marijuana use: Associations with young adults' use and consequences across days

BACKGROUND

Many young adults engage in simultaneous alcohol and marijuana (SAM) use so that their effects overlap. Little is known about motivations for dual substance use and associations with use and consequences. This study examined daily-level associations between cross-fading motives and levels of alcohol and marijuana use and consequences.

METHODS

Young adults who reported SAM use in the month prior were surveyed in two 14-day bursts. Data included 1049 SAM use days from 281 young adults (age 18-25; M age = 21.80, SD = 2.16; 50 % women). Multilevel models assessed between- and within-person effects of cross-fading motives (i.e., to enhance the effects of marijuana and/or alcohol use by using them simultaneously) on alcohol and marijuana use and consequences, after adjusting for general enhancement, social, coping, and conformity motives and the amount of alcohol and marijuana used that day.

RESULTS

On 76 % of SAM use days, participants endorsed cross-fading motives (i.e., to enhance the effect of alcohol or marijuana or to get drunk and high at the same time). Having stronger cross-fading motives was associated with greater alcohol use, perceived intoxication, and positive alcohol consequences at the between- and within-person levels. In addition, between-person, individuals who reported stronger cross-fading motives on average reported more negative alcohol consequences and positive marijuana consequences on average. Cross-fading motives on a given day were not associated with marijuana use or marijuana consequences that day.

CONCLUSIONS

Cross-fading motives were common and varied from day to day. Understanding the motivational context for dual substance use may support future interventions for cross-fading.

The relationship of cannabis decriminalization in Colorado and cannabis use in individuals with alcohol use disorders

OBJECTIVE

Over the past decade, cannabis use has become increasingly popular in states that include Colorado. During this time, alcohol use disorders (AUDs) and alcohol-related medical conditions have also been consistently recognized as public health problems with increasing prevalence in the state. Despite the widespread use of cannabis in Colorado, the epidemiology of cannabis use among those with AUDs has been poorly described. Therefore, we sought to examine cannabis use among individuals with likely AUDs and individuals with low-risk alcohol use during a time of major Colorado legislative changes before and after legalization of recreational cannabis in 2012.

METHODS

This study was a secondary data analysis conducted with information from 303 participants (80% male) in the Denver, CO metropolitan enrolled between August 2007 and April 2016 for studies related to alcohol and lung health. Of these participants, 188 (62%) were completing inpatient alcohol detoxification with likely AUDs. All participants completed the Alcohol Use Disorder Identification Test (AUDIT) to establish their likelihood of an AUD, and all had information on current cannabis use assessed by questionnaire and urine toxicology testing.

RESULTS

Individuals with likely AUDs more commonly used cannabis compared to control participants (42% vs 27%, p = 0.007). In multiple logistic regression analyses, participant type (likely AUD versus control), tobacco smoking, and age were significantly associated with cannabis smoking; however, the year of participant enrollment was not. Adjusted odds for cannabis use among participants with likely AUDs were 2.97 (1.51-5.82), p = 0.002, while odds for cannabis use among tobacco smokers were 3.67 (1.94-6.93), p < 0.0001. Among control participants, tobacco smoking increased odds of cannabis use seven-fold.

CONCLUSIONS

Our findings highlight the exceptionally high odds of cannabis use among individuals with likely AUDs undergoing alcohol detoxification at a Colorado treatment facility before and after legalization of recreational cannabis. Targeted investigations into the medical and psychiatric consequences of combined alcohol and cannabis use are urgently needed to define its health impact in these vulnerable individuals.

Consequences of alcohol and marijuana use among college students: Prevalence rates and attributions to substance-specific versus simultaneous use

College students who use alcohol and marijuana often use them simultaneously, so that their effects overlap. The present study examined whether negative consequences experienced by simultaneous alcohol and marijuana (SAM) users vary from those experienced by individuals who use alcohol and marijuana concurrently but not simultaneously (CAM) or single-substance users. We considered 9 types of consequences: cognitive, blackout, vomiting, academic/occupational, social, self-care, physical dependence, risky behaviors, and driving under the influence (DUI). Further, we examined whether consequences experienced by SAM users are attributed to using alcohol, marijuana, or both simultaneously. The sample included past-year alcohol and marijuana users age 18-24 (N = 1,390; 62% female; 69% White; 12% Hispanic) recruited from 3 U.S. college campuses. SAM users experienced a greater overall number of consequences than CAM or alcohol-only users, even controlling for frequency and intensity of alcohol and marijuana use and potentially confounding psychosocial and sociodemographic factors. Experiencing specific consequences differed between simultaneous and concurrent users, but after adjusting for consumption and other covariates, only blackouts differed. In contrast, SAM users were more likely to experience each consequence than alcohol-only users, with strongest effects for DUI, blackouts, and cognitive consequences. Among SAM users, consequences were most likely to be attributed to alcohol and were rarely attributed to simultaneous use. Being a user of both alcohol and marijuana and using alcohol and marijuana together so that their effects overlap each contribute to risk, suggesting there is value in targeting the mechanisms underlying type of user as well as those underlying type of use. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

The impact of decriminalization on marijuana and alcohol consumption in Jamaica

We examine whether marijuana decriminalization in Jamaica, a country that historically has had relatively widespread use of the drug, has led to an increase in its use, the frequency of use and the money spent on it. To this end, we use a national drug survey dataset with extensive information on people's use of, attitudes towards, access to marijuana. Our econometric analysis shows that awareness of the legislation has a positive correlation with the use of the substance. Worryingly, decriminalization positively correlates with the likelihood of first time and general use for youths. There is also some evidence that the legislation results in a substitution away from alcohol towards marijuana consumption for youths. From a policy perspective, a marijuana monitoring system can be implemented to follow the consumption patterns of youths. This should involve establishing school-level programmes that monitor students, and where potential drug users are identified, school officials should intervene to curb students' drug appetite before an escalated use of marijuana.

Binge and Cannabis Co-Use Episodes in Relation to White Matter Integrity in Emerging Adults

Background: Growing evidence suggests that cannabis and alcohol (and especially binge alcohol drinking) use independently alters neural structure and functioning, particularly during sensitive developmental time periods (e.g., emerging adulthood). However, few studies have investigated the effects of same-day use of these two substances. Here, white matter (WM) integrity was investigated in relation to binge alcohol drinking, cannabis, and same-day binge and cannabis co-use in adolescents and emerging adults. Methods: FreeSurfer's TRACULA was used to assess WM in emerging adults (n=75; 16-26 years old). Timeline Followback calculated past month cannabis use, binge episodes, and same-day cannabis and binge drinking co-use. Multiple regressions investigated WM by past month cannabis, binge, and co-use. Results: Results revealed co-use episodes were related to lower fractional anisotropy (FA), an overall measure of neuronal integrity, in three tracts (left inferior longitudinal fasciculus [ILF], p=0.02; right anterior thalamic radiation [ATR], p=0.01; and left cingulum cingulate gyrus [CCG], p=0.01); and lower axial diffusivity in left ILF (p=0.03). Cannabis use was significantly related to greater FA in left ILF (p=0.005), left ATR (p=0.02), right ATR (p=0.05), left CCG (p=0.006), right CCG (p=0.03), and right superior longitudinal fasciculus parietal (p=0.03). Binge episodes related to greater FA in right ATR (p=0.03). Conclusions: These findings suggest that co-use was associated with lower WM integrity across frontolimbic tracts. In addition, greater FA was related to greater cannabis use across several tracts and binge alcohol use in one tract. Co-users also appeared to be more severe substance users. Future research should investigate the potential independent and interactive effects of these substances on pre-clinical and clinical levels.

A phase 1, randomized, pharmacokinetic trial of the effect of different meal compositions, whole milk, and alcohol on cannabidiol exposure and safety in healthy subjects

OBJECTIVE

The pharmacokinetics (PK) and safety of single oral 750-mg doses of a plant-derived pharmaceutical formulation of highly purified cannabidiol (CBD; Epidiolex in the USA and Epidyolex in Europe; 100-mg/mL oral solution) were assessed in healthy adults following a high-fat/calorie meal (n = 15), a low-fat/calorie meal (n = 14), whole milk (n = 15), or alcohol (n = 14), relative to the fasted state (n = 29).

METHODS

Blood samples were collected until 96 hours postdose in each period and evaluated by liquid chromatography and tandem mass spectrometry. PK parameters (maximum observed plasma concentration [C_max ], area under the plasma concentration-time curve from time zero to the last observed quantifiable concentration, area under the concentration-time curve from time zero to infinity [AUC_0-∞ ], and time to maximum plasma concentration [t_max ]) of CBD and its major metabolites were derived using noncompartmental analysis.

RESULTS

CBD exposure increased by 3.8-fold for AUC_0-∞ and 5.2-fold for C_max when CBD was administered with a high-fat/calorie meal versus fasted. To a lesser extent, a low-fat/calorie meal enhanced CBD exposure versus fasted with a 2.7-fold increase in AUC_0-∞ and a 3.8-fold increase in C_max . Similarly, when dosed with whole milk, CBD exposure increased versus fasted by 2.4-fold for AUC_0-∞ and 3.1-fold for C_max . Modest elevations in CBD exposure occurred when it was dosed with alcohol: 1.6-fold for AUC_0-∞ and 1.9-fold for C_max . No clinically relevant effect of any test condition on CBD t_max or t_½ versus the fasted state was apparent. The same trend was seen for the CBD metabolites, except that 7-carboxy-cannabidiol t_max was considerably longer when CBD was administered with alcohol (14 vs 4 hours fasted). Inter- and intrasubject variability in PK parameters was moderate to high during the trial.

SIGNIFICANCE

CBD and metabolite exposures were most affected by a high-fat/calorie meal. CBD exposures also increased with a low-fat/calorie meal, whole milk, or alcohol, but to a lesser extent. CBD was tolerated, and there were no severe or serious adverse events during the trial.

Simultaneous alcohol and marijuana use in daily life: Implications for level of use, subjective intoxication, and positive and negative consequences

Simultaneous alcohol and marijuana (SAM) use is prevalent among young adult drinkers and associated with increased risk for harms. Less understood about SAM use is whether increased risk is incurred on SAM use occasions relative to occasions in which individuals used only 1 substance. From a sample of young adult SAM users, we compared occasions in which individuals simultaneously used alcohol and marijuana so that the effects overlapped ("SAM days"), occasions involving only alcohol ("alcohol days"), and occasions involving only marijuana ("marijuana days") on level of use, level of subjective intoxication, and negative and positive consequences. Eligible participants (N = 154; 57.8% female, 72.7% non-Hispanic/Latinx White) were 18-25 years old, reported past-month SAM use, and reported past 2-week binge drinking. Participants completed up to 14 daily assessments on their substance use behavior. Multilevel models indicated that, relative to alcohol days, SAM days had more negative consequences. SAM and alcohol days were not statistically different on level of use, level of subjective alcohol intoxication, or positive consequences. Relative to marijuana days, SAM days had more negative consequences and more positive consequences. Level of use (number of hits) and level of marijuana intoxication were not statistically different. In addition to SAM users being a more at-risk group, SAM occasions are associated with greater risk within this vulnerable population. Fine-grained ecological momentary assessments are needed to better understand perceptions and behavior throughout a SAM use episode. (PsycInfo Database Record (c) 2020 APA, all rights reserved).