Background: There are currently three FDA-approved medications for opioid use disorder (OUD), but none of them are especially effective, some can precipitate withdrawal in dependent individuals, and all of them require daily administration. In the appropriate settings, single administrations of psychedelics can elicit persistent anti-addiction effects in humans and in laboratory animals, but very few studies have assessed the potential therapeutic utility of psychedelics in OUD. Methods: We have recently established a model of oral opioid consumption in mice that captures an “addiction-like” phenotype characterized by induction of physical dependence and defense of opioid consumption when drug solutions are devalued. In these studies, we used this procedure to assess the effects of two different psychedelics on abuse-related effects of two distinct fentanyl analogs. Results: Mice consumed solutions of water, acryl fentanyl (AF), or 4-fluoroisobutyryl fentanyl (4-FIBF) for 2 h per day, 7 days per week, demonstrating postsession antinociceptive effects and becoming physically dependent. Four days after a single treatment with saline, lysergic acid diethylamide (LSD), or R (–)-2,5-dimethoxy-4-iodoamphetamine (DOI), mice were given access to their maintenance solutions, which were now adulterated with bitter quinine. In mice drinking water, quinine significantly decreased consumption, but mice consuming AF or 4-FIBF solutions defended their consumption despite the bitter taste. In all cases, treatment with LSD or DOI did not alter the defense of consumption observed with opioid solutions, suggesting no effects on opioid taking. Fifteen days after psychedelic treatment, mice were injected with the opioid antagonist naloxone, and withdrawal-associated jumping, restlessness, and thermal hyperalgesia were measured. Neither LSD nor DOI treatment altered naloxone-precipitated jumping or restlessness, but both psychedelics significantly attenuated withdrawal-associated thermal hyperalgesia. Conclusions: These data do not strongly support the use of a single exposure to psychedelics in the treatment of OUD but may suggest persistent effects of psychedelics on heightened pain perception typically observed in opioid withdrawal.

Novel analogs of the psychedelic lysergic acid diethylamide (LSD) have emerged on the gray market in recent years, typically containing substitutions to the ergoline scaffold on the indole (N1) nitrogen or at the diethylamide moiety. In these studies, we screened 4 N1-substituted drugs (1A-LSD, 1P-LSD, 1B-LSD, and 1CP-LSD) and 1 diethylamide-substituted drug (LSZ) in assays of serotonin receptor binding, LSD-like discriminative stimulus effects, and disposition in rat blood after systemic injection. As compared with LSD, we found that all of the N1-substituted drugs exhibited worse affinity for and/or weaker efficacy at 5-hydroxytryptamine (5-HT)1A, 5-HT2A, 5-HT2B, and 5-HT2C receptors, while LSZ displayed an LSD-like binding profile at these sites. Despite their impaired receptor affinities and efficacies, the N1-substituted compounds all fully substituted for LSD in the rat, as did the diethylamide-substituted LSZ. Following systemic injection of the N1-substituted drugs at doses producing full substitution for LSD, we detected similar high blood levels of LSD at time points relevant to the behavioral assay, suggesting that these compounds are converted to LSD in vivo. In contrast, LSZ was the only species detected after its administration, which, combined with its high-affinity binding and intrinsic efficacy at psychedelic-relevant receptors, implies that it is biologically active on its own. These studies highlighted the role of pharmacokinetics and analytical chemistry in connecting seemingly disparate in vitro and in vivo drug profiles and strongly implied that variability in human metabolism of these compounds may result in dramatically different pharmacologic effects across individuals. SIGNIFICANCE STATEMENT: Four N1-substituted lysergamides (1A-lysergic acid diethylamide [LSD], 1P-LSD, 1B-LSD, and 1CP-LSD) and 1 diethylamide-substituted drug were screened for serotonin receptor binding, LSD-like discriminative stimulus effects, and disposition in rat blood. Despite their generally impaired receptor binding profiles compared with LSD, all the N1-substituted lysergamides were LSD-like in vivo, most likely through metabolic conversion to LSD. In contrast, the diethylamide-substituted drug exhibited LSD-like affinities and efficacy at 5-hydroxytryptamine receptors, was not metabolically converted to LSD, and elicited potent LSD-like interoceptive effects.

Given that previous studies have provided mixed results on cathinone neurotoxicity, we compared the effects of 'functionally equivalent' dosing regimens of methamphetamine (METH), methcathinone, and α-pyrrolidinopropiophenone (α-PPP) on behavioral and neurochemical markers associated with dopaminergic alterations and cognitive function. Male Swiss Webster mice received METH (5 mg/kg), methcathinone (80 mg/kg), or α-PPP (80 mg/kg), using a 'binge'-like dosing regimen (q2h × 4, intraperitoneal). Body weight and temperature were recorded during dosing. Behavior was assessed 2-4 days later, followed by brain extraction. Motor function was evaluated by open-field testing and stride length analysis. Cognitive function was assessed with the passive avoidance test. Striatal levels of dopamine and its major metabolites were measured using ultra-HPLC. All three drug treatments induced weight loss. METH treatment produced a small, transient increase in rectal temperature (~1 °C); methcathinone and α-PPP did not. All three drug treatments impaired passive avoidance performance (P < 0.05 to P < 0.01), but none produced persistent motor deficits. METH and methcathinone treatment significantly reduced striatal dopamine levels (P < 0.001), whereas α-PPP did not, and only METH treatment increased homovanillic acid/dopamine turnover (P < 0.01). Only METH exposure triggered measurable changes in dopamine metabolism and a small, transient increase in temperature, highlighting its distinct neurochemical profile compared with methcathinone and α-PPP under these conditions. All three drug treatments impaired passive avoidance performance, but none caused lasting motor deficits, demonstrating that behavioral deficits can occur without persistent motor changes.

INTRODUCTION:Abuse potential assessment of drugs with central nervous system activity is a critical component of the development of new medications for regulatory filings for approval worldwide. These new drug applications typically include recommendations for scheduling status as a controlled substance, if scheduling is warranted. This commentary focuses on the approach and current issues related to scheduling in the United States (US) Controlled Substances Act (CSA); however, scheduling more globally generally involves similar approaches and issues. Although scheduling is intended to protect public health and safety by adequate restrictive control based on the abuse potential assessment, it is also intended to serve medicinal use and access and to incentivize the development of new medicines with reduced abuse-related risks. Thus, overly restrictive scheduling can present risks to public health, as does under-scheduling. OBJECTIVE:Identify the categories of substances and new drugs that appear most challenging for reliable and valid abuse potential assessment by the widely used abuse potential assessment approaches recommended in the U.S. Food and Drug Administration (FDA) 2017 Guidance and which generally serve globally. METHODOLOGY:A panel of abuse potential assessment experts convened at a scientific meeting that included many leading abuse potential and regulatory experts, namely the International Study Group Investigating Drugs as Reinforcers. The focus of the panel was novel and psychedelic substances and cannabinoids that raise challenges for accurate abuse potential assessment, in which postmarketing evaluations by the FDA suggested were overestimates of their abuse potential that resulted in overly restrictive scheduling. RESULTS:There is agreement that many novel acting substances, including medications for treating disorders related to anxiety, sleep, depression, and pain, and including orexin receptor acting substances, psychedelics, and diverse cannabinoids, may require modifications of existing methods and alternative approaches to more fully and accurately characterize their abuse potential and guide CSA scheduling. This included a human abuse potential (HAP) assessment that can raise challenges for the identification of the most appropriate placebo and positive comparators, study populations, and protocols to ensure both safety and scientific reliability. CONCLUSIONS:The core abuse potential methods that serve U.S. CSA scheduling and global new drug scheduling are generally reliable for many categories of drugs but need to be modified and perhaps supplemented with additional outcome measures to more fully and accurately characterize potential abuse-related risks. This may include behavioral economic assessments in preclinical and clinical studies and a broader range of outcome measures in HAP studies and adverse event assessment in all clinical studies in drug development programs.

Oral use of illicit fentanyl formulations is common, and these preparations may be contaminated with fentanyl analogs (FAs) with unknown pharmacological and toxicological properties. Route of administration impacts pharmacological effects, and pharmacokinetic or pharmacodynamic properties of oral fentanyl and FAs could influence aspects of opioid use disorder that are not necessarily present in animal models involving other routes of administration. We established oral consumption of water, or solutions of the FAs furanyl fentanyl and acryl fentanyl in C57 B l/6N mice. Consumption of pharmacologically-relevant concentrations of the FAs was reliably engendered, verified by induction of opioid-mediated antinociceptive effects in a warm-water tail withdrawal procedure, hypothermic effects, and observation of antagonist-precipitated withdrawal. When maintenance solutions were adulterated with the bitter tastant quinine, water control mice decreased their consumption, but mice consuming FA solutions defended their consumption, even at quinine concentrations that suppressed water drinking. Brief access to supplemental water, injection of the μ-opioid antagonist naltrexone, or administration of the μ-opioid agonist morphine all attenuated the defense of FA consumption. In all cases, the abuse-related effects of acryl fentanyl were greater than those of furanyl fentanyl. Consumption of acryl fentanyl also abolished weight gain across the study, and disrupted nest-building. The results of these experiments suggest that mice drinking furanyl fentanyl or acryl fentanyl experience opioid-mediated effects including antinociception, dependence and withdrawal, and abuse-related subjective effects, and provide proof of concept for use of this model to assess pharmacological and non-pharmacological manipulations which may attenuate the reinforcing effects of oral fentanyl and FAs.

Cannabis is one of the oldest and widely used substances in the world. Cannabinoids within the cannabis plant, known as phytocannabinoids, mediate cannabis’ effects through interactions with the body’s endogenous cannabinoid system. This endogenous system, the endocannabinoid system, has important roles in physical and mental health. These roles point to the potential to develop cannabinoids as therapeutic agents while underscoring the risks related to interfering with the endogenous system during nonmedical use. This scoping narrative review synthesizes the current evidence for both the therapeutic and adverse effects of the major (i.e., Δ9-tetrahydrocannabinol and cannabidiol) and lesser studied minor phytocannabinoids, from nonclinical to clinical research. We pay particular attention to the areas where evidence is well established, including analgesic effects after acute exposures and neurocognitive risks after acute and chronic use. In addition, drug development considerations for cannabinoids as therapeutic agents within the United States are reviewed. The proposed clinical study design considerations encourage methodological standards for greater scientific rigor and reproducibility to ultimately extend our knowledge of the risks and benefits of cannabinoids for patients and providers. SIGNIFICANCE STATEMENT This work provides a review of prior research related to phytocannabinoids, including therapeutic potential and known risks in the context of drug development within the United States. We also provide study design considerations for future cannabinoid drug development.

Select Drug Category Polydrug (i.e. concurrent use two or more drugs)Topic Drug InteractionsAbstract Detail Preclinical - In VivoAbstract Category Original Research Aim Reports of “Narcan-resistant” opioid overdose have proliferated in the media. One mechanism for this treatment resistance could be contamination of the opioid with a non-opioid drug which also suppresses respiration. The most commonly detected adulterants in street opioids are synthetic cannabinoid receptor agonists (SCRAs), which are not standard analytes in emergency toxicology screens. Limited evidence from humans and laboratory animals suggests that SCRAs depress respiration. We hypothesized that co-administration of fentanyl (FEN) with a SCRA would suppress respiration in an additive or synergistic manner, and that these effects would be resistant to reversal with naloxone. Methods Whole body plethysmography characterized respiratory depressant effects of the μ-opioid FEN and the SCRAs JWH-018 and 5F-ADB-PINACA, alone and in combination, in adult male NIH Swiss mice. The μ-antagonist naloxone, the CB1 antagonist rimonabant, or both antagonists together were also administered with FEN and the SCRAs. Results FEN and both SCRAs rapidly elicited respiratory depressant effects at similar doses, and the magnitude of these effects was similar across drugs. Naloxone attenuated respiratory depressant effects of FEN, but not those of the SCRAs, while rimonabant attenuated the effects of the SCRAs, but not those of FEN. Combining small doses of FEN and the SCRAs produced additive respiratory depressant effects. Attempts to “rescue” mice treated with the FEN + SCRA combination using a very large dose of naloxone only partially reversed respiratory depression. Similarly, “rescuing” mice with a large dose of rimonabant only partially reversed respiratory depression. Co-administration of the large doses of both antagonists also failed to fully reverse the respiratory depressant effects of FEN + SCRA. Conclusions Co-administration of opioids with SCRAs exacerbates respiratory depression and decreases the effectiveness of naloxone as an overdose reversal agent. Emergency toxicology screens should test for SCRAs during opioid overdose.

Abuse of novel arylcyclohexylamines (ACX) poses risks for toxicities, including adverse neurocognitive effects. In vivo effects of ring-substituted analogs of phencyclidine (PCP), eticyclidine (PCE), and ketamine are understudied. Adult male National Institutes of Health Swiss mice were used to assess locomotor effects of PCP and its 3-OH, 3-MeO, 3-Cl, and 4-MeO analogs, PCE and its 3-OH and 3-MeO analogs, and ketamine and its deschloro and 2F-deschloro analogs, in comparison with those of methamphetamine (METH), 3,4-methylenedioxymethamphetamine (MDMA), and two benzofuran analogs of MDMA. PCP-like interoceptive effects for all of these ACXs were determined using a food-reinforced drug discrimination procedure in adult male Sprague Dawley rats. A novel operant assay of rule-governed behavior incorporating aspects of attentional set-shifting was used to profile psychosis-like neurocognitive effects of PCP and 3-Cl-PCP in rats, in comparison with cocaine and morphine. PCP-like ACXs were more effective locomotor stimulants than the amphetamines, PCE-like ACXs were as effective as the amphetamines, and ketamine-like ACXs were less effective than the amphetamines. Addition of -Cl, -OH, or -OMe at the 3-position on the aromatic ring did not impact locomotor effectiveness, but addition of -OMe at the 4-position reduced locomotor effectiveness. Lethal effects were induced by drugs with -OH at the 3-position or -OMe at the 3- or 4-position. All novel ACXs substituted at least partially for PCP, and PCP and 3-Cl-PCP elicited dose-dependent psychosis-like neurocognitive deficits in the rule-governed behavior task not observed with cocaine or morphine. Novel ACXs exhibit substantial abuse liability and toxicities not necessarily observed with their parent drugs. SIGNIFICANCE STATEMENT: Novel arylcyclohexylamine analogs of PCP, PCE, and ketamine are appearing on the illicit market, and abuse of these drugs poses risks for toxicities, including adverse neurocognitive effects. These studies demonstrate that the novel ACXs exhibit PCP-like abuse liability in the drug discrimination assay, elicit varied locomotor stimulant and lethal effects in mice, and induce psychosis-like neurocognitive effects in rats.

Substitutions to the phenethylamine structure give rise to numerous amphetamines and cathinones, contributing to an ever-growing number of abused novel psychoactive substances. Understanding how various substitutions affect the pharmacology of phenethylamines may help lawmakers and scientists predict the effects of newly emerging drugs. Here, we established structure-activity relationships for locomotor stimulant and monoamine transporter effects of 12 phenethylamines with combinations of para-chloro, β-keto, N-methyl, or N-ethyl additions. Automated photobeam analysis was used to evaluate effects of drugs on ambulatory activity in mice, whereas in vitro assays were used to determine activities at transporters for dopamine (DAT), norepinephrine (NET), and 5-HT (SERT) in rat brain synaptosomes. In mouse studies, all compounds stimulated locomotion, except for 4-chloro-N-ethylcathinone. Amphetamines were more potent stimulants than their β-keto counterparts, while para-chloro amphetamines tended to be more efficacious than unsubstituted amphetamines. Para-chloro compounds also produced lethality at doses on the ascending limbs of their locomotor dose-effect functions. The in vitro assays showed that all compounds inhibited uptake at DAT, NET, and SERT, with most compounds also acting as substrates (i.e., releasers) at these sites. Unsubstituted compounds displayed better potency at DAT and NET relative to SERT. Para-chloro substitution or increased N-alkyl chain length augmented relative potency at SERT, while combined para-chloro and N-ethyl substitutions reduced releasing effects at NET and DAT. These results demonstrate orderly SAR for locomotor stimulant effects, monoamine transporter activities, and lethality induced by phenethylamines. Importantly, 4-chloro compounds produce toxicity in mice that suggests serious risk to humans using these drugs in recreational contexts.

Background: Humans often administer psychostimulants in party or music festival settings characterized by warm ambient temperatures, which may impact drug effects; however, preclinical studies rarely investigate drug effects at multiple ambient temperatures. Work with 3,4-methylenedioxymethamphetamine (MDMA) and 3,4methylenedioxypyrovalerone (MDPV) suggests that the presence of a 3,4-methylenedioxy ring moiety may influence ambient temperature-dependent effects.Methods: Locomotor activity and conditioned place preference dose-response curves were generated at 20 & PLUSMN;2 degrees C for two amphetamine analogues (MDMA and methamphetamine [METH]) and two cathinone analogues (MDPV and & alpha;-pyrrolidinopentiophenone [& alpha;PVP]) in mice. Effects were then redetermined at 29 & PLUSMN;2 degrees C for each drug and assay.Results: All four drugs elicited dose-dependent locomotor stimulation at the cool ambient temperature. At the warm ambient temperature, MDMA and MDPV produced sensitization to stereotypy, whereas METH and & alpha;PVP produced sensitization to locomotor activity. Regarding place conditioning, the warm ambient environment potentiated place preference elicited by doses of METH and & alpha;PVP that were sub-threshold in the cool ambient environment, but attenuated the effects of analogous doses of MDMA and MDPV. Conclusions: These studies suggest that warmer ambient temperatures may potentiate typical stimulant effects for the drugs lacking the 3,4-methylenedioxy ring, but may potentiate the behaviorally toxic/adverse effects for the drugs containing a 3,4-methylenedioxy ring. Thus, preclinical abuse liability studies conducted at standard laboratory temperatures may not fully capture the effects of psychostimulants and highlight the need to model the environments in which drugs are typically used by humans.

Polysubstance use makes up a majority of drug use, yet relatively few studies investigate the abuse-related effects of drug mixtures. Dose-addition analyses provide a rigorous and quantitative method to determine the nature of the interaction (i.e., supraadditive, additive, or subadditive) between two or more drugs. As briefly reviewed here, studies in rhesus monkeys have applied dose-addition analyses to group level data to characterize the nature of the interaction between the reinforcing effects of stimulants and opioids (e.g., mixtures of cocaine + heroin). Building upon these foundational studies, more recent work has applied dose-addition analyses to better understand the nature of the interaction between caffeine and illicit stimulants such as MDPV and methamphetamine in rats. In addition to utilizing a variety of operant procedures, including drug discrimination, drug self-administration, and drug-primed reinstatement, these studies have incorporated potency and effectiveness ratios as a method for both statistical analysis and visualization of departures from additivity at both the group and individual subject level. As such, dose-addition analyses represent a powerful and underutilized approach to quantify the nature of drug-drug interactions that can be applied to a variety of abuse-related endpoints in order to better understand the behavioral pharmacology of polysubstance use.

Alcohol-use disorder (AUD) remains a major public health concern. In recent years, there has been a heightened interest in components of the endocannabinoid system for the treatment of AUD. Cannabinoid type 1 (CB1) receptors have been shown to modulate the rewarding effects of alcohol, reduce the abuse-related effects of alcohol, improve cognition, exhibit anti-inflammatory, and neuroprotective effects, which are all favorable properties of potential therapeutic candidates for the treatment of AUD. However, CB1 agonists have not been investigated for the treatment of AUD because they stimulate the motivational properties of alcohol, increase alcohol intake, and have the tendency to be abused. Preclinical data suggest significant potential for the use of CB1 antagonists to treat AUD; however, a clinical phase I/II trial with SR14716A (rimonabant), a CB1 receptor antagonist/inverse agonist showed that it produced serious neuropsychiatric adverse events such as anxiety, depression, and even suicidal ideation. This has redirected the field to focus on alternative components of the endocannabinoid system, including cannabinoid type 2 (CB2) receptor agonists as a potential therapeutic target for AUD. CB2 receptor agonists are of particular interest because they can modulate the reward pathway, reduce abuse-related effects of alcohol, reverse neuroinflammation, improve cognition, and exhibit anti-inflammatory and neuroprotective effects, without exhibiting the psychiatric side effects seen with CB1 antagonists. Accordingly, this article presents an overview of the studies reported in the literature that have investigated CB2 receptor agonists with regards to AUD and provides commentary as to whether this receptor is a worthy target for continued investigation.

Drug developers worldwide assess compound safety and efficacy using measures that include mouse core temperature and locomotor activity. Subtle differences in animal housing conditions between institutions can alter these values, impacting scientific rigor and reproducibility. In these studies, adult male NIH Swiss mice were surgically implanted with radiotelemetry probes that simultaneously monitored core temperature and locomotor activity across various housing conditions. In the first study, ambient temperature was varied between 20 °C and 28°C in groups of singly housed mice. Additional studies held the mice at a constant ambient temperature and examined the effects of cage density (housing animals singly or in groups of 3 or 6), bedding change and provision of nesting material, and the availability of a running wheel on core temperature and locomotor activity. Mice overwhelmingly maintained species-typical core temperatures across all ambient temperatures, across all housing conditions, when bedding was fresh or old, and with or without the provision of cotton squares as nesting material. However, engaging in wheel running and the combination of fresh bedding and cotton squares transiently increased core temperatures beyond the species-typical range. Similarly, the circadian distribution of locomotor activity was significantly disrupted by placing animals in cages with fresh bedding or nesting material, or by performing both of these manipulations concurrently during the light period. These findings suggest that standard husbandry practices and common housing conditions may transiently affect core temperature in adult mice. Furthermore, these practices may have profound and relatively long-lasting effects on motor activity and the regulation of circadian rhythms.

While classical cathinones, such as methcathinone, have been shown to be monoamine releasing agents at human monoamine transporters, the subgroup of α-pyrrolidinophenones has thus far solely been characterized as monoamine transporter reuptake inhibitors. Herein, we report data from previously undescribed α-pyrrolidinopropiophenone (α-PPP) derivatives and compare them with the pharmacologically well-researched α-PVP (α-pyrrolidinovalerophenone). Radiotracer-based in vitro uptake inhibition assays in HEK293 cells show that the investigated α-PPP derivatives inhibit the human high-affinity transporters of dopamine (hDAT) and norepinephrine (hNET) in the low micromolar range, with α-PVP being ten times more potent. Similar to α-PVP, no relevant pharmacological activity was found at the human serotonin transporter (hSERT). Unexpectedly, radiotracer-based in vitro release assays reveal α-PPP, MDPPP and 3Br-PPP, but not α-PVP, to be partial releasing agents at hNET (EC50 values in the low micromolar range). Furthermore, uptake inhibition assays at low-affinity monoamine transporters, i.e., the human organic cation transporters (hOCT) 1-3 and human plasma membrane monoamine transporter (hPMAT), bring to light that all compounds inhibit hOCT1 and 2 (IC50 values in the low micromolar range) while less potently interacting with hPMAT and hOCT3. In conclusion, this study describes (i) three new hybrid compounds that efficaciously block hDAT while being partial releasers at hNET, and (ii) highlights the interactions of α-PPP-derivatives with low-affinity monoamine transporters, giving impetus to further studies investigating the interaction of drugs of abuse with OCT1-3 and PMAT.

While classical cathinones, such as methcathinone, have been shown to be monoamine releasing agents at human monoamine transporters, the subgroup of alpha-pyrrolidinophenones has thus far solely been characterized as monoamine transporter reuptake inhibitors. Herein, we report data from previously undescribed alpha-pyrrolidinopropiophenone (alpha-PPP) derivatives and compare them with the pharmacologically well-researched alpha-PVP (alpha-pyrrolidinovalerophenone). Radiotracer-based in vitro uptake inhibition assays in HEK293 cells show that the investigated alpha-PPP derivatives inhibit the human high-affinity transporters of dopamine (hDAT) and norepinephrine (hNET) in the low micromolar range, with alpha-PVP being ten times more potent. Similar to alpha-PVP, no relevant pharmacological activity was found at the human serotonin transporter (hSERT). Unexpectedly, radiotracer-based in vitro release assays reveal alpha-PPP, MDPPP and 3Br-PPP, but not alpha-PVP, to be partial releasing agents at hNET (EC50 values in the low micromolar range). Furthermore, uptake inhibition assays at low-affinity monoamine transporters, i.e., the human organic cation transporters (hOCT) 1-3 and human plasma membrane monoamine transporter (hPMAT), bring to light that all compounds inhibit hOCT1 and 2 (IC50 values in the low micromolar range) while less potently interacting with hPMAT and hOCT3. In conclusion, this study describes (i) three new hybrid compounds that efficaciously block hDAT while being partial releasers at hNET, and (ii) highlights the interactions of alpha-PPP-derivatives with low-affinity monoamine transporters, giving impetus to further studies investigating the interaction of drugs of abuse with OCT1-3 and PMAT.

Alcohol‐use disorder (AUD) is the third leading cause of preventable death in the United States following tobacco and obesity, and current treatments for AUD yield disappointing remission rates. Chronic alcohol intake has been established to negatively impact the body’s immune system, and the endocannabinoid system has been shown to modulate the abuse‐related effects of ethanol. In this study, and we investigated the effects of 30 mg/kg caryophyllene oxide ( BCPO), in two widely accepted animal models of AUD: two‐bottle choice ethanol consumption and ethanol‐induced conditioned place preference (CPP). Finally, we used multiplex bead‐based flow cytometry to evaluate the effect of BCPO on plasma level of cytokines following these behavioral assays. BCPO significantly decreased ethanol intake and preference without changing total fluid intake in mice that consumed high amounts of ethanol. In mice that consumed low amounts of ethanol, BCPO did not alter ethanol intake, preference, or total fluid intake. BCPO significantly attenuated the expression of an ethanol‐induced CPP. Following the CPP assay, we observed a significant decrease in circulating levels of IFNγ, TNFα, MCP1, IL12p70, IL1b, and IL10 which was reversed by treatment with BCPO. Our findings support the current knowledge that excessive consumption of alcohol may lead to immune suppression and predispose individuals to a number of infections as well as neoplastic diseases. This study expands and supports the use of immunoregulatory molecules as a viable target for the treatment of AUD.