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Alcohol and Cannabinoids - From the Editors

Jane Metrik1,2 and Sachin Patel3

1Center for Alcohol and Addiction Studies, Brown University School of Public Health, Providence, Rhode Island

2Providence Veterans Affairs Medical Center, Providence, Rhode Island

3Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, Illinois

    Alcohol is frequently used in association with cannabis, with co-use now perceived as normative with expanding cannabis legalization. Cannabinoid products are increasingly used for a number of medical and recreational purposes, including to enhance alcohol-reinforcing properties or in some cases to substitute for alcohol. Rates of alcohol use disorder (AUD) are higher among cannabis users relative to nonusers, with approximately 60% of individuals with current cannabis use disorder also meeting criteria for current AUD.1,2 Co-use is linked with heavy and problematic alcohol consumption, which in turn increases risk of alcohol-related diseases such as alcohol-associated liver disease. Co-use is also linked with a number of negative consequences, including behavioral risks,3 risk for driving safety, psychiatric comorbidity, adverse health effects, and poor alcohol treatment outcomes.4 However, the impact of cannabinoids on alcohol-related morbidity is not well understood, and findings on the impact of cannabis use on alcohol-related behaviors are equivocal. Cannabis serves both to complement drinking (i.e., increasing alcohol use), leading to more harmful consequences, and to substitute for alcohol effects (i.e., decreasing alcohol use and minimizing related risks).5 Beyond simultaneous (i.e., same-session) or temporally independent (e.g., same-week) co-use patterns, the substantial variability in cannabinoid composition (i.e., tetrahydrocannabinol [THC]-to-cannabidiol ratio), formulations (e.g., smoked, edibles), and quantity of cannabis could influence the direction of effect on alcohol-related outcomes. Further, individual differences associated with age and neurodevelopment; substance use disorders;6 motives for cannabis, alcohol, and simultaneous use;7 and the impact of state-level cannabis and alcohol regulatory policies8 could contribute to mixed findings on the risks and benefits of cannabinoids in relation to alcohol-related behaviors.

    This research review series approaches cannabinoid–alcohol co-use through the lens of complex interactions between biological, psychological, and environmental factors. Basic science research reviewed in this topic series highlights the role of the endogenous cannabinoid or endocannabinoid (eCB) system in alcohol-related behaviors. The eCB system, which regulates cannabis reinforcement, is also involved in modulating alcohol reinforcement, motivation to consume alcohol, excessive alcohol consumption, AUD,9-11 and alcohol-related diseases. Emerging preclinical literature implicates exogenous cannabinoid receptor agonists (e.g., THC) in increased alcohol consumption, with chronic exposure to alcohol implicated in disruptions in eCB signaling.12,13 THC is the primary psychoactive constituent that interacts with the eCB system, producing intoxicating, rewarding, and reinforcing effects in a dose-dependent function. Although THC is the most commonly studied cannabinoid that defines cannabis potency, there are more than 100 other phytocannabinoids and more than 500 constituents in the cannabis plant that also may exert different effects on alcohol-related outcomes. For example, cannabidiol (CBD) is a nonpsychoactive, plant-based cannabinoid that has been implicated in the medicinal value of cannabis due to its potential antioxidant, anti-inflammatory, and analgesic effects.

    Cannabinoids may reduce harmful effects of AUD, in part, by conferring beneficial effects on the gastrointestinal and immune systems.14-16 Endogenous cannabinoids, which are lipid molecules that exhibit cannabinoid-like properties, regulate various physiological functions in both the central nervous system and the peripheral organs, including the liver. Endocannabinoids and cannabinoid receptors in the liver modulate the progression of alcohol-related liver diseases via their effects on immune function, metabolic function, and inflammatory response.17 Preclinical research on the efficacy of eCB degradation inhibitors indicates that these inhibitors show promise as an emerging therapeutic target for AUD and cannabis use disorder treatment.18-20 Evidence from preclinical models also suggests CBD may have promise as a candidate pharmacotherapy for AUD.21 CBD attenuates proximal alcohol-related behaviors (e.g., preference, stress-induced alcohol seeking) and reduces alcohol consumption22,23 and alcohol-related physiological harms (e.g., liver steatosis and fibrosis, brain damage) in animal models.24-26 Overall, there is growing recognition of the therapeutic potential of the eCB system in reducing negative affective states associated with AUD and with abstinence from alcohol in AUD patients.27 Clinical studies on the acute and chronic impacts of specific cannabinoid and eCB targets on clinically relevant alcohol outcomes will help pave the way toward efficacious AUD pharmacotherapy and treatment of related medical conditions.

    This translational research series strives to elucidate the cannabinoid–alcohol interactions by synthesizing findings across animal studies as well as human laboratory and epidemiological designs from community and clinical samples. From synapse to policy, the reviews in this series reflect the current state of the science on the reciprocal impact of alcohol and cannabinoids on an individual and the society at large. Several comprehensive reviews summarize findings from preclinical and human studies on the effects of alcohol exposure on the eCB system as a whole28 and more specifically at the synaptic level in the brain.29 In their review of the mechanisms of cannabinoid receptor signaling in hepatic pathogenesis, Yang, Choi, and Jeong summarize evidence in support of cannabinoid-based treatments for alcohol-associated liver disease.30 Lees, Debenham, and Squeglia present a comprehensive overview of longitudinal neuropsychological and neuroimaging studies on the independent and combined effects of cannabis and alcohol use on the developing human brain.31 Several articles review findings on the impact of cannabis use on alcohol consumption and consequences, and how this association may differ by cannabis formulation or by user characteristics,32 with a specific focus on simultaneous alcohol and cannabis use, and contextual characteristics of co-use in young adults.33 Finally, Pacula et al. provide a systematic review of published studies on the effect of liberalization of cannabis policies on alcohol use and co-use with cannabis in the United States and Canada.34

    This topic series aligns with the research efforts discerning the shared impact of cannabinoids and alcohol on health undertaken by the Collaborative Research on Addiction at the National Institutes of Health (CRAN) partnership between the National Institute on Alcohol Abuse and Alcoholism, the National Institute on Drug Abuse (NIDA), and the National Cancer Institute. Elucidating effects of cannabis and alcohol co-use on health, policy, and economy is also a key research priority identified by the Cannabis Policy Research Workgroup of the NIDA National Advisory Council on Drug Abuse (NOT-DA-22-003). The empirical literature on cannabis and alcohol co-use has grown fourfold in the last decade alone, reflecting burgeoning interest in this topic. As summarized in the articles in this series, more research is needed to improve our understanding of the mechanisms underlying the functioning of eCBs in relation to alcohol in order to advance the development of eCB-based pharmacological treatments of AUD and related conditions. Clinical data examining the role of specific cannabinoids in alcohol-related human behavior also are critically needed to inform clinical guidelines for individuals engaged in AUD treatment and/or people who drink heavily and co-use cannabis. The authors lend crucial insights and make specific recommendations for future research endeavors on alcohol and cannabis interactions, taking into account between-person and within-person variability across time and contexts. All together, these findings will have important implications for the development of policy concerning alcohol in the context of the changing cannabis sociopolitical landscape.

    Acknowledgments

    This work was supported by the National Institute on Alcohol Abuse and Alcoholism under grant number R01AA024091.

    Correspondence

    Address correspondence concerning this article to Jane Metrik, Center for Alcohol and Addiction Studies, Brown University School of Public Health, Providence, RI, 02903. Email: Jane_Metrik@brown.edu

    Disclosures

    J.M. declares no competing financial or nonfinancial interests. S.P. is a scientific consultant for Psy Therapeutics and Jazz Pharmaceuticals.

    Publisher's note

    Opinions expressed in contributed articles do not necessarily reflect the views of the National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health. The U.S. government does not endorse or favor any specific commercial product or commodity. Any trade or proprietary names appearing in Alcohol Research: Current Reviews are used only because they are considered essential in the context of the studies reported herein.

    References

     

    1. Hayley AC, Stough C, Downey LA. DSM-5 cannabis use disorder, substance use and DSM-5 specific substance-use disorders: Evaluating comorbidity in a population-based sample. Eur Neuropsychopharmacol. 2017;27(8):732-743. https://doi.org/10.1016/j.euroneuro.2017.06.004.
    2. Substance Abuse and Mental Health Services Administration, Center for Behavioral Health Statistics and Quality. Results From the 2018 National Survey on Drug Use and Health: Detailed tables. Rockville, MD: Center for Behavioral Health Statistics and Quality, Substance Abuse and Mental Health Services Administration. Published online 2019. https://www.samhsa.gov/data.
    3. Jackson KM, Stevens AK, Sokolovsky AW, Hayes KL, White HR. Real-world simultaneous alcohol and cannabis use: An ecological study of situational motives and social and physical contexts. Psychol Addict Behav. 2021;35(6):698-711. https://doi.org/10.1037/adb0000765.
    4. Subbaraman MS, Metrik J, Patterson D, Swift R. Cannabis use during treatment for alcohol use disorders predicts alcohol treatment outcomes. Addiction. 2017;112(4):685-694. https://doi.org/10.1111/add.13693.
    5. Subbaraman MS. Substitution and complementarity of alcohol and cannabis: A review of the literature. Subst Use Misuse. 2016;51(11):1399-1414. https://doi.org/10.3109/10826084.2016.1170145.
    6. Metrik J, Gunn RL, Jackson KM, Sokolovsky AW, Borsari B. Daily patterns of marijuana and alcohol co-use among individuals with alcohol and cannabis use disorders. Alcohol Clin Exp Res. 2018;42(6):1096-1104. https://doi.org/10.1111/acer.13639.
    7. Patrick ME, Fairlie AM, Lee CM. Motives for simultaneous alcohol and marijuana use among young adults. Addict Behav. 2018;76:363-369. https://doi.org/10.1016/j.addbeh.2017.08.027.
    8. Smart R, Pacula RL. Early evidence of the impact of cannabis legalization on cannabis use, cannabis use disorder, and the use of other substances: Findings from state policy evaluations. Am J Drug Alcohol Abuse. 2019;45(6):644-663. https://doi.org/10.1080/00952990.2019.1669626.
    9. Colombo G, Serra S, Vacca G, Carai MAM, Gessa GL. Endocannabinoid system and alcohol addiction: Pharmacological studies. Pharmacol Biochem Behav. 2005;81(2):369-380. https://doi.org/10.1016/j.pbb.2005.01.022.
    10. López-Moreno JA, Echeverry-Alzate V, Bühler K-M. The genetic basis of the endocannabinoid system and drug addiction in humans. J Psychopharmacol. 2012;26(1):133-143. https://doi.org/10.1177/0269881111416689.
    11. Hungund BL, Basavarajappa BS. Role of endocannabinoids and cannabinoid CB1 receptors in alcohol-related behaviors. Ann N Y Acad Sci. 2004;1025(1):515-527. https://doi.org/10.1196/annals.1316.064.
    12. Basavarajappa BS. Endocannabinoid system and alcohol abuse disorders. In: Bukiya A (ed.). Recent Advances in Cannabinoid Physiology and Pathology. Advances in Experimental Medicine and Biology. 2019;1162:89-127. https://doi.org/10.1007/978-3-030-21737-2_6.
    13. Pava MJ, Woodward JJ. A review of the interactions between alcohol and the endocannabinoid system: Implications for alcohol dependence and future directions for research. Alcohol. 2012;46(3):185-204. https://doi.org/10.1016/j.alcohol.2012.01.002.
    14. Karoly HC, Mueller RL, Bidwell LC, Hutchison KE. Cannabinoids and the microbiota–gut–brain axis: Emerging effects of cannabidiol and potential applications to alcohol use disorders. Alcohol Clin Exp Res. 2020;44(2):340-353. https://doi.org/10.1111/acer.14256.
    15. Nair MP, Figueroa G, Casteleiro G, Muñoz K, Agudelo M. Alcohol versus cannabinoids: A review of their opposite neuro-immunomodulatory effects and future therapeutic potentials. J Alcohol Drug Depend. 2015;3(1):184.
    16. Sharkey KA, Wiley JW. The role of the endocannabinoid system in the brain-gut axis. Gastroenterology. 2016;151(2), 252-266. https://doi.org/10.1053/j.gastro.2016.04.015.
    17. Kunos G. Interactions between alcohol and the endocannabinoid system. Alcohol Clin Exp Res. 2020;44(4):790-805. https://doi.org/10.1111/acer.14306.
    18. Zhou Y, Schwartz BI, Giza J, Gross SS, Lee FS, Kreek MJ. Blockade of alcohol escalation and “relapse” drinking by pharmacological FAAH inhibition in male and female C57BL/6J mice. Psychopharmacology (Berl). 2017;234(19):2955-2970. https://doi.org/10.1007/s00213-017-4691-9.
    19. Blednov YA, Cravatt BF, Boehm SL, Walker D, Harris RA. Role of endocannabinoids in alcohol consumption and intoxication: Studies of mice lacking fatty acid amide hydrolase. Neuropsychopharmacology. 2007;32(7):1570-1582. https://doi.org/10.1038/sj.npp.1301274.
    20. Cippitelli A, Cannella N, Braconi S, et al. Increase of brain endocannabinoid anandamide levels by FAAH inhibition and alcohol abuse behaviours in the rat. Psychopharmacology (Berl). 2008;198(4):449-460. https://doi.org/10.1007/s00213-008-1104-0.
    21. Turna J, Syan SK, Frey BN, et al. Cannabidiol as a novel candidate alcohol use disorder pharmacotherapy: A systematic review. Alcohol Clin Exp Res. 2019;43(4):550-563. https://doi.org/10.1111/acer.13964.
    22. Gonzalez-Cuevas G, Martin-Fardon R, Kerr TM, et al. Unique treatment potential of cannabidiol for the prevention of relapse to drug use: Preclinical proof of principle. Neuropsychopharmacology. 2018;43(10):2036-2045. https://doi.org/10.1038/s41386-018-0050-8.
    23. Viudez-Martínez A, García-Gutiérrez MS, Navarrón CM, et al. Cannabidiol reduces ethanol consumption, motivation and relapse in mice. Addict Biol. 2018;23(1):154-164. https://doi.org/10.1111/adb.12495.
    24. Wang Y, Mukhopadhyay P, Cao Z, et al. Cannabidiol attenuates alcohol-induced liver steatosis, metabolic dysregulation, inflammation and neutrophil-mediated injury. Sci Rep. 2017;7(1):12064. https://doi.org/10.1038/s41598-017-10924-8.
    25. Yang L, Rozenfeld R, Wu D, Devi LA, Zhang Z, Cederbaum A. Cannabidiol protects liver from binge alcohol-induced steatosis by mechanisms including inhibition of oxidative stress and increase in autophagy. Free Radic Biol Med. 2014;68:260-267. https://doi.org/10.1016/j.freeradbiomed.2013.12.026.
    26. Hamelink C, Hampson A, Wink DA, Eiden LE, Eskay RL. Comparison of cannabidiol, antioxidants, and diuretics in reversing binge ethanol-induced neurotoxicity. J Pharmacol Exp Ther. 2005;314(2):780-788. https://doi.org/10.1124/jpet.105.085779.
    27. Bedse G, Centanni SW, Winder DG, Patel S. Endocannabinoid signaling in the central amygdala and bed nucleus of the stria terminalis: Implications for the pathophysiology and treatment of alcohol use disorder. Alcohol Clin Exp Res. 2019;43(10):2014-2027. https://doi.org/10.1111/acer.14159.
    28. Serrano A, Natividad L. Alcohol-endocannabinoid interactions: Implications for addiction-related behavioral processes. Alcohol Res. 2022;42(1):09. https://doi.org/10.35946/arcr.v42.1.09.
    29. Wolfe SA, Vozella V, Roberto M. The synaptic interactions of alcohol and the endogenous cannabinoid system. Alcohol Res. 2022;42(1):03. https://doi.org/10.35946/arcr.v42.1.03.
    30. Yang K, Choi SE, Jeong W-I. Hepatic cannabinoid signaling in the regulation of alcohol-associated liver disease. Alcohol Res. 2021;41(1):12. https://doi.org/10.35946/arcr.v41.1.12.
    31. Lees B, Debenham J, Squeglia, LM. Alcohol and cannabis use and the developing brain. Alcohol Res. 2021;41(1):11. https://doi.org/10.35946/arcr.v41.1.11.
    32. Gunn RL, Aston ER, Metrik J. Patterns of cannabis and alcohol co-use: Substitution versus complementary effects. Alcohol Res. 2022;42(1):04. https://doi.org/10.35946/arcr.v42.1.04.
    33. Lee CM, Calhoun BH, Abdallah DA, et al. Simultaneous alcohol and marijuana use among young adults: A scoping review of prevalence, patterns, psychosocial correlates, and consequences. Alcohol Res. 2022;42(1):08. https://doi.org/10.35946/arcr.v42.1.08.
    34. Pacula RL, Smart R, Lira MC, Pessar SC, Blanchette JG, Naimi TS. Relationships of cannabis policy liberalization with alcohol use and co-use with cannabis: A narrative review. Alcohol Res. 2022;42(1):06. https://doi.org/10.35946/arcr.v42.1.06.