Gabapentin for the treatment of alcohol use disorder

Advancements in addressing drug dependence: A review of promising therapeutic strategies and interventions

Substance dependence represents a pervasive global concern within the realm of public health. Presently, it is delineated as a persistent and recurrent neurological disorder stemming from drug-triggered neuroadaptations in the brain's reward circuitry. Despite the availability of various therapeutic modalities, there has been a steady escalation in the mortality rate attributed to drug overdoses. Substantial endeavors have been directed towards the exploration of innovative interventions aimed at mitigating cravings and drug-induced repetitive behaviors. Within this review, we encapsulate the most auspicious contemporary treatment methodologies, accentuating meta-analyses of efficacious pharmacological and non-pharmacological approaches: including gabapentin, topiramate, prazosin, physical exercise regimens, and cerebral stimulation techniques.

Management of alcohol-associated liver disease and alcohol use disorder in liver transplant candidates and recipients: Challenges and opportunities

Alcohol-associated liver disease poses a significant global health burden, with rising alcohol consumption and prevalence of alcohol use disorder (AUD) contributing to increased morbidity and mortality. This review examines the challenges and opportunities in the care of candidates and recipients of liver transplant (LT) with AUD. Despite advancements in posttransplant patient survival, the risk of disease recurrence and alcohol relapse remains substantial. Several challenges have been identified, including (1) rising disease burden of alcohol-associated liver disease, variable transplant practices, and systemic barriers; (2) disparities in mental health therapy access and the impact on transplant; (3) variable definitions, underdiagnosis, and stigma affecting access to care; and (4) post-LT relapse, its risk factors, and consequential harm. The review focuses on the opportunities to improve AUD care for candidates and recipients of LT through effective biochemical monitoring, behavioral and pharmacologic approaches, creating Centers of Excellence for post-LT AUD care, advocating for policy reforms, and ensuring insurance coverage for necessary services as essential steps toward improving patient outcomes. The review also highlights unmet needs, such as the scarcity of addiction specialists, and calls for further research on personalized behavioral treatments, digital health, and value-based care models to optimize AUD care in the LT setting.

Successful Synergistic Use of Gabapentin With Other Antiepileptic Drugs in the Management of Lance-Adams Syndrome Complicated by Alcohol Withdrawal Seizures: A Case Report

OBJECTIVE

Lance-Adams syndrome is a rare and debilitating disorder characterized by successful cardiopulmonary resuscitation resulting in myoclonus activity. Alcohol withdrawal seizures from alcohol use disorder may further exacerbate Lance-Adams syndrome. We aim to present a case of Lance-Adams syndrome complicated by alcohol withdrawal seizures and successfully treated with a combination of valproate, clonazepam, and gabapentin.

MATERIALS AND METHODS

The patient's electronic medical record, direct patient care experiences, and a comprehensive literature search were used for this case report. We report a 41-year-old male patient with Lance-Adams syndrome with concurrent alcohol use disorder. Treatment was improved when adding gabapentin for alcohol use disorder treatment, alongside combination antiepileptic therapy. A PubMed search was conducted to examine Lance-Adams syndrome case reports of successful combination antiepileptic therapy, with a secondary evaluation of patients with concurrent alcohol use disorder.

RESULTS

The literature search yielded 18 articles, which resulted in 21 individual cases in which combination antiepileptic drug therapy was successful in treating myoclonus secondary to Lance-Adams syndrome; however, none of the case reports utilized gabapentin synergistically. One case described Lance-Adams syndrome complicated by alcohol consumption and similar to our patient, the patient used alcohol to abolish myoclonic activity.

CONCLUSIONS

To the best of our knowledge, this is the first case report documenting a patient with Lance-Adams syndrome and concurrent alcohol use disorder, with a positive effect of gabapentin use. Gabapentin, when used for alcohol use disorder treatment, may be an appropriate adjunct agent in the management of patients receiving combination antiepileptic therapy for the treatment of Lance-Adams syndrome.

Multi-modal neuroimaging reveals differences in alcohol-cue reactivity but not neurometabolite concentrations in adolescents who drink alcohol

BACKGROUND

The objective of this multi-modal neuroimaging study was to identify neuroscience-informed treatment targets for adolescent alcohol use disorder (AUD) by examining potential neural alterations associated with adolescent alcohol use.

METHODS

Adolescents (ages 17-19) who heavily used (n=49) or did not use alcohol (n=22) were recruited for a multi-modal neuroimaging protocol, including proton magnetic resonance spectroscopy within the dorsal anterior cingulate cortex (dACC) and an fMRI alcohol cue-reactivity task. The alcohol cue-reactivity task was analyzed across 11 a priori regions-of-interest (ROI), including the dACC, and in an exploratory whole-brain approach. Correlations were run between neurometabolite levels and alcohol cue-reactivity in the dACC.

RESULTS

There were no significant group differences in absolute neurometabolite concentrations. Compared to the control group, the alcohol-using group exhibited heightened alcohol cue reactivity in the left amygdala ROI (p=0.04). The whole-brain approach identified higher alcohol cue reactivity in the alcohol-using group compared to controls in the amygdala and occipital regions, and lower reactivity in the parietal lobe. Whole-brain sex effects were noted, with females displaying higher reactivity regardless of group. No significant correlations were found between neurometabolite levels and alcohol cue-reactivity in the dACC.

CONCLUSIONS

The null neurometabolic findings may be due to age, relatively low severity of alcohol use, and non-treatment-seeking status of the participants. Females showed overall higher reactivity to alcohol cues, indicating a sex effect regardless of alcohol use history. Higher amygdala reactivity in alcohol-using adolescents suggests that emotional processing related to alcohol cues may be a useful target for future adolescent AUD interventions.

Reward, relief, and habit drinking profiles in treatment seeking individuals with an AUD

AIMS

This study aimed to compare reward, relief, and habit treatment-seeking individuals on recent drinking, alcohol use disorder (AUD) phenomenology, and mood. The second aim of the study was to evaluate the predictive validity of reward, relief, and habit profiles.

METHOD

Treatment-seeking individuals with an AUD (n = 169) were recruited to participate in a medication trial for AUD (NCT03594435). Reward, relief, and habit drinking groups were assessed using the UCLA Reward Relief Habit Drinking Scale. Group differences at baseline were evaluated using univariate analyses of variance. A subset of participants were enrolled in a 12-week, double-blind, placebo-controlled medication trial (n = 102), and provided longitudinal drinking and phenomenology data. The predictive validity of group membership was assessed using linear regression analyses.

RESULTS

At baseline, individuals who drink primarily for relief had higher craving and negative mood than those who drink for reward and habit. Prospectively, membership in the relief drinking group predicted greater alcohol use, greater heavy drinking, and fewer days abstinent compared to those in the reward drinking group. Membership in the relief drinking group also predicted greater alcohol craving, more alcohol-related consequences, and more anxiety symptoms over 12 weeks compared to those in the reward drinking group.

CONCLUSIONS

This study provides support for reward and relief drinking motive profiles in treatment-seeking individuals with an AUD. Membership in the relief drinking motive group was predictive of poorer drinking outcomes and more negative symptomology over 12 weeks, indicating that individuals who drink for relief may be a particularly vulnerable sub-population of individuals with AUD.

Astrocytic GABAergic Regulation in Alcohol Use and Major Depressive Disorders

Gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the central nervous system (CNS). Most GABAergic neurons synthesize GABA from glutamate and release it in the synaptic cleft in the CNS. However, astrocytes can also synthesize and release GABA, activating GABA receptors in the neighboring neurons in physiological and pathological conditions. As the primary homeostatic glial cells in the brain, astrocytes play a crucial role in regulating GABA homeostasis and synaptic neurotransmission. Accumulating evidence demonstrates that astrocytic GABA dysregulation is implicated in psychiatric disorders, including alcohol use disorder (AUD) and major depressive disorder (MDD), the most prevalent co-occurring psychiatric disorders. Several current medications and emerging pharmacological agents targeting GABA levels are in clinical trials for treating AUD and MDD. This review offers a concise summary of the role of astrocytic GABA regulation in AUD and MDD. We also provide an overview of the current understanding and areas of debate regarding the mechanisms by which astrocytes regulate GABA in the CNS and their potential significance in the molecular basis of AUD and MDD, paving the way toward future research directions and potential therapeutic target areas within this field.

Alcohol Use Disorder Treatment: Problems and Solutions

Alcohol use disorder (AUD) afflicts over 29 million individuals and causes more than 140,000 deaths annually in the United States. A heuristic framework for AUD includes a three-stage cycle-binge/intoxication, withdrawal/negative affect, and preoccupation/anticipation-that provides a starting point for exploring the heterogeneity of AUD with regard to treatment. Effective behavioral health treatments and US Food and Drug Administration-approved medications are available but greatly underutilized, creating a major treatment gap. This review outlines challenges that face the alcohol field in closing this treatment gap and offers solutions, including broadening end points for the approval of medications for the treatment of AUD; increasing the uptake of screening, brief intervention, and referral to treatment; addressing stigma; implementing a heuristic definition of recovery; engaging early treatment; and educating health-care professionals and the public about challenges that are associated with alcohol misuse. Additionally, this review focuses on broadening potential targets for the development of medications for AUD by utilizing the three-stage heuristic model of addiction that outlines domains of dysfunction in AUD and the mediating neurobiology of AUD.

Closing the Care Gap: Management of Alcohol Use Disorder in Patients with Alcohol-associated Liver Disease

Alcohol-associated liver disease (ALD)-related morbidity and mortality are rising in the United States. Although effective medications and behavioral interventions are available for the treatment of patients with alcohol use disorder (AUD), patients with ALD are profoundly undertreated for AUD. This article reviews the management of AUD in patients with ALD, with a focus on appropriate screening and diagnosis, management of alcohol withdrawal syndrome, pharmacotherapy for AUD, alcohol biomarkers, and behavioral interventions. Expanding access to AUD treatment is imperative for improving health outcomes in patients with ALD.

Multidisciplinary Care of Alcohol-related Liver Disease and Alcohol Use Disorder: A Narrative Review for Hepatology and Addiction Clinicians

PURPOSE

Models of integrated, multidisciplinary care are optimal in the setting of complex, chronic diseases and in the overlap of medical and mental health disease, both of which apply to alcohol-related liver disease (ALD). Alcohol use disorder (AUD) drives nearly all cases of ALD, and coexisting mental health disease is common. ALD is a complex condition with severe clinical manifestations and high mortality that can occasionally lead to liver transplantation. As a result, integrated care for ALD is an attractive proposition. The aim of this narrative review was to: (1) review the overlapping and concerning trends in the epidemiology of AUD and ALD; (2) use a theoretical framework for integrated care known as the "five-component model" as a basis to highlight the need for integrated care and the overlapping clinical manifestations and management of the 2 conditions; and (3) review the existing applications of integrated care in this area.

METHODS

We performed a narrative review of epidemiology, clinical manifestations, and management strategies in AUD and ALD, with a particular focus on areas of overlap that are pertinent to clinicians who manage each disease. Previously published models were reviewed for integrating care in AUD and ALD, both in the general ALD population and in the setting of liver transplantation.

FINDINGS

The incidences of AUD and ALD are rising, with a pronounced acceleration driven by the Coronavirus Disease 2019 pandemic. Hepatologists are underprepared to diagnose and treat AUD despite its high prevalence in patients with liver disease. A patient who presents with overlapping clinical manifestations of both AUD and ALD may not fit neatly into typical treatment paradigms for each individual disease but rather will require new management strategies that are appropriately adapted. As a result, the dimensions of integrated care, including collective ownership of shared goals, interdependence among providers, flexibility of roles, and newly created professional activities, are highly pertinent to the holistic management of both diseases.

IMPLICATIONS

Integrated care models have proliferated as recognition grows of the dual pathology of AUD and ALD. Ongoing coordination across disciplines and research in the fields of hepatology and addiction medicine are needed to further elucidate optimal mechanisms for collaboration and improved quality of care.

N-acetylcysteine does not alter neurometabolite levels in non-treatment seeking adolescents who use alcohol heavily: A preliminary randomized clinical trial

Current treatments for adolescent alcohol use disorder (AUD) are mainly psychosocial and limited in their efficacy. As such, pharmacotherapies are being investigated as potential adjunctive treatments to bolster treatment outcomes. N-acetylcysteine is a promising candidate pharmacotherapy for adolescent AUD because of its tolerability and demonstrated ability to modulate glutamatergic, GABAergic, and glutathione systems. The primary objective of this double-blind, placebo-controlled, within-subjects crossover preliminary investigation was to measure potential changes within glutamate + glutamine (Glx), GABA, and glutathione levels in the dorsal anterior cingulate cortex (dACC) using proton magnetic resonance spectroscopy during 10-days of N-acetylcysteine (1200 mg twice daily) compared to 10-days of placebo in non-treatment seeking adolescents who use alcohol heavily (N = 31; 55% female). Medication adherence was confirmed via video. Effects on alcohol use were measured using Timeline Follow-Back as an exploratory aim. Linear mixed effects models controlling for baseline metabolite levels, brain tissue composition, alcohol use, cannabis use, and medication adherence found no significant differences in Glx, GABA, or glutathione levels in the dACC after N-acetylcysteine compared to placebo. There were also no measurable effects on alcohol use; however, this finding was underpowered. Findings were consistent in the subsample of participants who met criteria for AUD (n = 19). The preliminary null findings in brain metabolite levels may be due to the young age of participants, relatively low severity of alcohol use, and non-treatment seeking status of the population investigated. Future studies can use these findings to conduct larger, well-powered studies within adolescents with AUD.

Dissecting operant alcohol self-administration using saccharin-fading procedure

BACKGROUND

Although alcohol use disorder is a complex human pathology, the use of animal models represents an opportunity to study some aspects of this pathology. One of the most used paradigms to study the voluntary alcohol consumption in rodents is operant self-administration (OSA).

AIMS

In order to facilitate the performance of this paradigm, we aim to describe some critical steps of OSA under a saccharin-fading procedure.

MATERIAL & METHODS

We used 40 male Wistar rats to study the process of acquiring the operant response through a saccharin-fading procedure under a fixed ratio (FR1) schedule of reinforcement. Next, we analyze the alcohol introduction and concentration increase, the effect of an alcohol deprivation, and the analogy between this paradigm with the Drinking in the Dark-Multiple Scheduled Access paradigm.

RESULTS

During alcohol concentration increase, animals reduced their lever presses in accordance with the increase in alcohol concentration. On the contrary, the consumption measured in g·kg^-1 BW showed a great stability. The lever presses pattern within operant session changes with the introduction of different alcohol concentrations: at higher alcohol concentrations, animals tended to accumulate most of their presses in the initial period of the session.

DISCUSSION

We show the utility of fading with low concentrations of saccharin and the evolution of the operant response through the different concentrations of alcohol.

CONCLUSION

Taken together, our results aimed to dissect the acquisition and maintenance of OSA behavior as well as other related variables, to facilitate the understanding and performance of this paradigm.

Medications for the Treatment of Alcohol Dependence-Current State of Knowledge and Future Perspectives from a Public Health Perspective

No single effective therapy for alcohol abuse has been found, despite it being a serious sociological and economic problem for hundreds of years. It seems difficult to find a single drug as a panacea for the alcohol problem due to the complexity of the pathophysiology of alcohol dependence. The purpose of this narrative review is to review existing and potentially future pharmaceuticals for the treatment of alcohol dependence in the most affordable way possible. Psychotherapy is the mainstay of treatment for alcoholism, while few drugs approved by legislators are available in the augmentation of this treatment, such as acamprosate, disulfiram, and naltrexone, approved by the FDA, and nalmefene by the EMA. There are recent reports in the literature on the possibility of using baclofen, topiramate, varenicline, and gabapentin in the treatment of alcohol dependence. Moreover, the results of recent clinical trials using psychoactive substances such as psilocybin and MDMA appear to be a breakthrough in the modern treatment of alcohol abuse. Despite this initial optimism, a lot of scientific effort is still needed before new pharmacological methods supporting the treatment of alcohol dependence syndrome will be widely available.

Cell therapy for neuropathic pain

Neuropathic pain (NP) is caused by a lesion or a condition that affects the somatosensory system. Pathophysiologically, NP can be ascribed to peripheral and central sensitization, implicating a wide range of molecular pathways. Current pharmacological and non-pharmacological approaches are not very efficacious, with over half of NP patients failing to attain adequate pain relief. So far, pharmacological and surgical treatments have focused primarily on symptomatic relief by modulating pain transduction and transmission, without treating the underlying pathophysiology. Currently, researchers are trying to use cell therapy as a therapeutic alternative for the treatment of NP. In fact, mounting pre-clinical and clinical studies showed that the cell transplantation-based therapy for NP yielded some encouraging results. In this review, we summarized the use of cell grafts for the treatment of NP caused by nerve injury, synthesized the latest advances and adverse effects, discussed the possible mechanisms to inform pain physicians and neurologists who are endeavoring to develop cell transplant-based therapies for NP and put them into clinical practice.

Gabapentin to treat acute alcohol withdrawal in hospitalized patients: A systematic review and meta-analysis

BACKGROUND

Gabapentin is an antiepileptic medication with evidence of benefit in alcohol use disorder patients. The mechanism of action of gabapentin may also benefit patients suffering from acute alcohol withdrawal syndrome (AWS).

METHODS

A systematic review and meta-analysis were conducted to examine if gabapentin can effectively replace/reduce the use of benzodiazepines for the treatment of acute alcohol withdrawal symptoms in hospitalized patients. Time to alcohol withdrawal symptom resolution, amount of benzodiazepines administered, rate of resolution of alcohol withdrawal symptoms, serious withdrawal-related complications, and hospital length of stay (LOS) were examined.

RESULTS

Eight retrospective studies (n = 2030) were included in this meta-analysis. There were no studies that examined study outcomes for patients who received only gabapentin and no benzodiazepines; in all studies, gabapentin-treated patients may have received benzodiazepines prior to gabapentin. There were no significant differences between gabapentin-treated and benzodiazepine-treated groups in time to symptom resolution, amount benzodiazepines administered, withdrawal-related complications, or LOS. There was a significant difference in the rate of symptom resolution favoring gabapentin-treated patients (p = 0.05); however, this analysis included only one study. Subgroup analyses of severe AWS patients revealed a significant decrease in LOS (p = 0.04) and a decrease in amount of benzodiazepines administered (p = 0.02) in gabapentin-treated patients, but these analyses included only one study. Subgroup analysis of patients receiving only gabapentin without benzodiazepines found a significantly decreased LOS in the gabapentin group compared to the benzodiazepine group (p < 0.001), but this analysis included only two studies.

CONCLUSIONS

There is insufficient evidence to support the widespread use of gabapentin to treat inpatients suffering AWS. All studies included in this meta-analysis are retrospective with high risk of confounding. Well-designed, randomized, controlled studies of gabapentin to treat patients with AWS are required.

Looking Back, Looking Forward: Current Medications and Innovative Potential Medications to Treat Alcohol Use Disorder

This article is part of a Festschrift commemorating the 50th anniversary of the National Institute on Alcohol Abuse and Alcoholism (NIAAA). Established in 1970, first as part of the National Institute of Mental Health and later as an independent institute of the National Institutes of Health, NIAAA today is the world's largest funding agency for alcohol research. In addition to its own intramural research program, NIAAA supports the entire spectrum of innovative basic, translational, and clinical research to advance the diagnosis, prevention, and treatment of alcohol use disorder and alcohol-related problems. To celebrate the anniversary, NIAAA hosted a 2-day symposium, "Alcohol Across the Lifespan: 50 Years of Evidence-Based Diagnosis, Prevention, and Treatment Research," devoted to key topics within the field of alcohol research. This article is based on Dr. Mason's presentation at the event. NIAAA Director George F. Koob, Ph.D., serves as editor of the Festschrift.

Off-label and investigational drugs in the treatment of alcohol use disorder: A critical review

Compounds known to be successful in the treatment of alcohol use disorder include the aversive agent, Disulfiram, the glutamatergic NMDA receptor antagonist, Acamprosate, and the opioid receptor antagonists, Naltrexone and Nalmefene. Although all four are effective in maintaining abstinence or reduction of alcohol consumption, only a small percentage of patients receive pharmacological treatment. In addition, many other medications have been investigated for their therapeutic potential in the treatment of alcohol use disorder. In this review we summarize and compare Baclofen, Gabapentin, Topiramate, Ondansetron, Varenicline, Aripiprazole, Quetiapine, Clozapine, Antidepressants, Lithium, Neuropeptide Y, Neuropeptide S, Corticotropin-releasing factor antagonists, Oxytocin, PF-05190457, Memantine, Ifenprodil, Samidorphan, Ondelopran, ABT-436, SSR149415, Mifepristone, Ibudilast, Citicoline, Rimonabant, Surinabant, AM4113 and Gamma-hydroxybutyrate While some have shown promising results in the treatment of alcohol use disorder, others have disappointed and should be excluded from further investigation. Here we discuss the most promising results and highlight medications that deserve further preclinical or clinical study. Effective, patient-tailored treatment will require greater understanding provided by many more preclinical and clinical studies.

Addition of a clinical pharmacist practitioner to an inpatient addiction triage team and related medication outcomes

Introduction

At a Veterans Affairs Medical Center (VAMC), a clinical pharmacist practitioner (CPP) was added to an inpatient addiction triage team in August 2019 to provide education and recommendations regarding medications for alcohol use disorder (MAUD) and opioid use disorder (MOUD). Before the addition of the CPP, missed opportunities for MAUD and MOUD education and prescribing prior to discharge on non-psychiatric units were observed.

Methods

This was a single-center, single-site, retrospective, observational cohort study with a primary objective to compare initiation rates of MAUD/MOUD 12 months before and after the addition of the CPP to the addiction triage team. Secondary end points included 90-day medication possession ratio, 1- and 3-month emergency department visit rates, 1- and 3-month hospital readmission rates, and opioid education and naloxone distribution interventions for eligible patients with a diagnosis of opioid use disorder.

Results

Both statistically and clinically significant improvements in MAUD/MOUD initiation rates were found in the CPP intervention group compared with the historical control group (26.3% vs 4%, P < .0001). Although secondary end points within this review were not found to be statistically significant, improvements were seen in the CPP intervention group compared with the historical control group related to medication possession ratio, and emergency department and hospital readmission rates.

Discussion

This study highlights the potential utility of a CPP to an inpatient addiction triage team to improve MAUD/MOUD prescribing rates in appropriate patients prior to discharge. Overall, the introduction of a CPP to an inpatient addiction triage team was feasible, well received by interprofessional team members, and required limited additional resources.

Psychiatric Uses of Gabapentin

OBJECTIVE

This article reviews evidence-based psychiatric uses of gabapentin, along with associated risks.

METHOD OF RESEARCH

An extensive literature review was conducted, primarily of articles searchable in PubMed, relating to psychiatric uses, safety, and adverse effects of gabapentin.

RESULTS

Evidence supports gabapentin as a treatment for alcohol withdrawal and alcohol use disorder. There is sufficient evidence to consider gabapentin as a third-line treatment for social anxiety disorder and severe panic disorder. Evidence does not support the use of gabapentin for bipolar disorder, major depressive disorder (MDD), posttraumatic stress disorder (PTSD), obsessive compulsive disorder (OCD), stimulant use disorder, or opioid withdrawal. Risks of gabapentin use are highest among those with a history of a substance use disorder and those concurrently taking opioids.

CONCLUSION

While gabapentin has a place in psychiatry for a select few indications, the literature does not support its use for many studied diagnoses.

A Retrospective Study of the Adjunctive Use of Gabapentin With Benzodiazepines for the Treatment of Benzodiazepine Withdrawal

Benzodiazepine withdrawal is a widespread problem with potentially severe and deadly consequences. Currently, the only medications available for treating benzodiazepine withdrawal are short-acting and long-acting benzodiazepines. Identifying other drugs to help in treating benzodiazepine withdrawal is necessary. Gabapentin, an anxiolytic drug that is also used off-label to treat alcohol withdrawal, is a potential candidate for modulating benzodiazepine withdrawal. Using electronic records from a large inpatient psychiatric facility, a retrospective study of 172 patients presenting with benzodiazepine withdrawal was conducted to determine if the coincidental use of gabapentin for other medical conditions was associated with better outcomes of benzodiazepine withdrawal (N=57 gabapentin, N=115 no gabapentin). The primary outcomes were hospital length of stay and total amount of benzodiazepines given (lorazepam milligram equivalent). In this retrospective analysis of electronic medical record data, the patients experiencing benzodiazepine withdrawal who received gabapentin as an adjunct to the use of benzodiazepines were administered a smaller amount of benzodiazepines and had a shorter length of hospital stay relative to the comparison group who did not receive adjunctive gabapentin. These results suggest the potential use of gabapentin as an adjunct to the use of benzodiazepines for treating benzodiazepine withdrawal. The limitations of this study included a small sample size and variability in medication management strategies across the sample.

Management of Post-Acute Alcohol Withdrawal: A Mixed-Studies Scoping Review

OBJECTIVE

This article reviews research on post-acute alcohol withdrawal syndrome (PAWS) management.

METHOD

We conducted a PRISMA (Preferred Reporting Items for Systematic Revision and Meta-Analyses)-guided scoping review of the published PAWS literature, searching six electronic databases (from their inception through December 2020) for English-language randomized and nonrandomized studies.

RESULTS

A total of 16 treatment studies met the inclusion criteria. The strength of evidence overall for pharmacologic treatments is low, with often only short-term results being reported, small treatment samples used, or inconsistent results found. However, for negative affect and sleep symptoms, more evidence supports using gabapentinoids (gabapentin and pregabalin) and anticonvulsants (carbamazepine and oxcarbazepine). Although preliminary data support acamprosate, there were no controlled trials. Despite an older treatment trial showing some positive data for amitriptyline for mood, the clinical measures used were problematic, and side effects and safety profile limit its utility. Finally, there is no evidence that melatonin and other agents (homatropine, Proproten-100) show PAWS symptoms.

CONCLUSIONS

Although there is some evidence for targeted pharmacotherapy for treating specific PAWS symptoms, there are few recent, robust, placebo-controlled trials, and the level of evidence for treatment efficacy is low.

The pharmacotherapeutic management of comorbid bipolar disorder and alcohol use disorder

INTRODUCTION

Comorbidity of bipolar disorder (BD) and alcohol use disorder (AUD) is very frequent resulting in detrimental outcomes, including increased mortality. Diagnosis of AUD in BD and vice versa is often delayed as symptoms of one disorder mimic and obscure the other one. Evidence for pharmacotherapies for people with comorbid BD and AUD remains limited, and further proof-of-concept studies are urgently needed.

AREAS COVERED

This paper explores the currently available pharmacotherapies for AUD, BD and their usefulness for comorbid BD and AUD. It also covers to some degree the epidemiology, diagnosis, and potential common neurobiological traits of comorbid BD and AUD.

EXPERT OPINION

The authors conclude that more controlled studies are needed before evidence-based guidance can be drawn up for clinician's use. Since there are no relevant pharmacological interactions, approved medications for AUD can also be used safely in BD. For mood stabilization, lithium should be considered first in adherent persons with BD and comorbid AUD. Alternatives include valproate, lamotrigine, and some atypical antipsychotics, with partial D2/D3 receptor agonism possibly being beneficial in AUD, too.

Medications and Patient Factors Associated With Increased Readmission for Alcohol-Related Diagnoses

Objective

To investigate medication factors and patient characteristics associated with readmissions following alcohol-related hospitalizations.

Patients and Methods

Adult patients admitted from September 1, 2016, through August 31, 2019, who had an alcohol-related hospitalization were identified through electronic health records. Patient characteristics and medications of interest administered during hospitalization or prescribed at discharge were identified. Medications of interest included US Food and Drug Administration–approved medications for alcohol use disorder, benzodiazepines, barbiturates, gabapentin, opioids, and muscle relaxants. The primary outcome was to identify medications and patient factors associated with 30-day alcohol-related readmission. Secondary outcomes included medications and patient characteristics associated with multiple alcohol-related readmissions within a year from the index admission (ie, two or more readmissions) and factors associated with 30-day all-cause readmission.

Results

Characteristics of the 932 patients included in this study associated with a 30-day alcohol-related readmission included younger age, severity of alcohol withdrawal, history of psychiatric disorder, marital status, and the number of prior alcohol-related admission in the previous year. Benzodiazepine or barbiturate use during hospitalization or upon discharge was associated with 30-day alcohol-related readmission (P=.006). Gabapentin administration during hospitalization or upon discharge was not associated with 30-day alcohol-related readmission (P=.079).

Conclusion

The findings reinforce current literature identifying patient-specific factors associated with 30-day readmissions. Gabapentin use was not associated with readmissions; however, there was an association with benzodiazepine/barbiturate use.

Integrated Care of Alcohol-Related Liver Disease

BACKGROUND/AIMS

Alcohol-related liver disease (ALD) is the medical manifestation of alcohol use disorder, a prevalent psychiatric condition. Acute and chronic manifestations of ALD have risen in recent years especially in young people and ALD is now a leading indication of liver transplantation (LT) worldwide. Such alarming trends raise urgent and unanswered questions about how medical and psychiatric care can be sustainably integrated to better manage ALD patients before and after LT.

METHODS

Critical evaluation of the interprofessional implications of broad and multifaceted ALD pathophysiology, general principles of and barriers to interprofessional teamwork and care integration, and measures that clinicians and institutions can implement for improved and integrated ALD care.

RESULTS

The breadth of ALD pathophysiology, and its numerous medical and psychiatric comorbidities, ensures that no single medical or psychiatric discipline is adequately trained and equipped to manage the disease alone.

CONCLUSIONS

Early models of feasible ALD care integration have emerged in recent years but much more work is needed to develop and study them. The future of ALD care is an integrated approach led jointly by interprofessional medical and psychiatric clinicians.

Alcohol Use Disorder: TheRole of Medication in Recovery

The misuse of alcohol in the United States continues to take a large toll on society, resulting in the deaths of about 88,000 Americans per year. Moreover, it is estimated that nearly 14.6 million Americans currently meet diagnostic criteria for current alcohol use disorder (AUD). However, very few individuals receive treatment, with an even smaller portion receiving medications approved by the U.S. Food and Drug Administration (FDA) for the treatment of AUD, despite scientifically rigorous evidence showing the benefits of combining medication approved for treating AUD with evidence-based behavioral therapy. These benefits include higher rates of abstinence and less risk of relapse to heavy drinking, with associated improvements in medical and mental health and in quality of life. This review provides an overview of FDA-approved medications and “off-label” drugs for the treatment of AUD. The article emphasizes that AUD medical advice and prescription recommendations should come from professionals with training in the treatment of AUD and that treatment plans should consider medication in conjunction with evidence-based behavioral therapy. Finally, this review notes the limited number of medications available and the continued need for the development of new pharmacotherapies to optimize AUD recovery goals.

Case Report: Diabetic urinary auto-brewery and review of literature

Background: Although candiduria is an expected encounter and should not be surprising in uncontrolled diabetes with glucose-enriched urine, urinary auto-brewery is rarely thought of by diabetologists. Moreover, endogenous ethanol production in humans from gut microbiome, urinary tract fungi and bacteria, and intermediary metabolism, has been reported for a long time, particularly in diabetics. 

Case description: To alert physicians to the overlooked implication of endogenously produced ethanol both as a biomarker for poor control of diabetes and as a complicating factor, we report this case of an elderly male smoker alcohol-abstinent insulin-dependent Type 2 diabetic patient. Because of circumstantial treatment and incompliance for one week, he developed endogenously produced alcohol intoxication. We proposed candidal urinary auto-brewery evidence sourced from the case history, urinalysis, and culture/identification tests - without excluding other sources. Fortunately, his diet and glycemic control were fairly controlled and, liver and kidney functions were almost normal. Amphotericin B I/V for five days, insulin, and a fluid therapy regimen greatly improved the case and cleared both the candiduria and ethanol from the urine and blood and the patient regained his base-line normal life.  

Conclusion: Symptoms of alcohol intoxication should be expected in patients with uncontrolled diabetes that most often correlates with candiduria and/or constipation. These symptoms can be exaggerated in those already suffering a degree of dementia and/or comorbid psychiatric/neurologic affections. Direct wet mount examination of urine under phase contrast microscopy would show the budding yeast cells.  Appropriate antifungal, insulin and fluid therapies regained the base-line norms.

Alcohol-Related Liver Disease: Basic Mechanisms and Clinical Perspectives

Alcohol-related liver disease (ALD) refers to the liver damage occurring due to excessive alcohol consumption and involves a broad spectrum of diseases that includes liver steatosis, steatohepatitis, hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). The progression of ALD is mainly associated with the amount and duration of alcohol usage; however, it is also influenced by genetic, epigenetic, and environmental factors. The definite diagnosis of ALD is based on a liver biopsy, although several non-invasive diagnostic tools and serum biomarkers have emerging roles in the early detection of ALD. While alcohol abstinence and nutritional support remain the cornerstone of ALD treatment, growing evidence has revealed that the therapeutic agents that target oxidative stress or gut-liver axis, inflammatory response inhibition, and liver regeneration enhancement also play a role in ALD management. Furthermore, microRNAs modulation and mesenchymal stem cell-based therapy have emerging potential as ALD therapeutic options. This review summarizes the updated understanding of the pathophysiology, diagnosis, and novel therapeutic approaches for ALD.

Gabapentin attenuates somatic signs of precipitated THC withdrawal in mice

Cannabis is the most frequently used federally illicit substance in the United States. However, there are currently no FDA-approved pharmacotherapies to mitigate the withdrawal symptoms associated with cessation in heavy users. A promising, readily available, non-cannabinoid therapy are the gabapentinoids. Although currently approved for epilepsy and neuropathic pain, gabapentinoids are increasingly used for their "off-label" efficacy in treating various psychiatric conditions and substance abuse. Gabapentin (GBP) synergizes with cannabinoid agonism in neuropathic pain models, substitutes for Δ⁹-tetrahydrocannabinol (THC) in drug discrimination procedures, and reduced withdrawal symptoms in an outpatient clinical trial. However, there are limited data on the biological plausibility of the therapeutic action of gabapentinoids in cannabinoid withdrawal in preclinical models. The purpose of the current study was to determine the efficacy of GBP on attenuating THC withdrawal in mice, using an array of tests targeting withdrawal-induced and withdrawal-suppressed behaviors. Separate cohorts of male and female mice were administered THC (10 mg/kg, s.c.) or vehicle for 5.5 days, and withdrawal was precipitated by the CB₁ antagonist rimonabant (2 or 3 mg/kg, i.p.) on the sixth day. GBP (≥10 mg/kg) reduced somatic signs of withdrawal (i.e., paw tremors and head twitches), but had no effect in locomotor activity or conditioned place preference. GBP (50 mg/kg) also restored withdrawal-suppressed responding on a progressive ratio reinforcement schedule. However, GBP (50 mg/kg) had no effect in withdrawal-suppressed marble burying or tail suspension struggling and did not normalize the stress response induced by THC withdrawal, as indicated by plasma corticosterone. These data suggest gabapentin may be effective at treating cannabinoid withdrawal symptoms including somatic and affective symptoms but may act independently of endocrine stress activation.

[Pharmacotherapy of alcohol withdrawal: update and new developments]

Bislang sind nur wenige Medikamente zur pharmakologischen Rückfallprophylaxe der Alkoholabhängigkeit zugelassen. Neben dem in Deutschland nicht mehr vertriebenen Disulfiram sind es die Opioidantagonisten Naltrexon und Nalmefen sowie das vermutlich über glutamaterge Neurone wirkende Acamprosat. Baclofen und γ‑Hydroxybutyrat (GHB) sind in einzelnen Ländern zugelassen. Wirkstoffe wie z. B. Vareniclin, Gabapentin und Topiramat können für die Rückfallprophylaxe der Alkoholabhängigkeit von Interesse sein, jedoch ist bislang keine Zulassung erfolgt. Vor dem Hintergrund der zur Revision anstehenden S3-Leitlinie zur Diagnose und Behandlung alkoholbezogener Störungen wird der heutige Kenntnisstand zur Pharmakotherapie der Alkoholabhängigkeit dargestellt.

Gabapentinoids for treatment of alcohol use disorder: A systematic review and meta-analysis

OBJECTIVE

Gabapentin (GBP) and pregabalin (PGB) have been used to treat alcohol use disorder (AUD) and alcohol withdrawal, but with inconsistent results. In this meta-analysis, we explored the effects of GBP/PGB treatment on AUD and their effects on withdrawal, craving, depression, and sleep disturbance in AUD patients.

METHODS

We carried out a systematic review and meta-analysis of randomized controlled trials comparing the effects of GBP/PGB on AUD with those of a placebo or control treatment. Electronic databases were searched for relevant articles published before September 2019. The primary outcome was defined as the efficacy measure on achieving abstinence or reducing alcohol consumption in a hierarchical order. We included 16 studies in our meta-analysis.

RESULTS

Overall, GBP had no significant benefit comparing to placebo or control treatment (Hedges' g = 0.0725, p = 0.6743). For specific alcohol-related outcome, GBP had significant effect on percentage of heavy drink (Hedges' g = 0.5478, p = 0.0441) and alcohol withdrawal symptoms (Hedges' g = 0.2475, p = 0.0425). GBP/PGB did not have significant beneficial effect on craving, depressive symptoms, or sleep disturbance. Instability was shown in sensitivity analyses of some above results.

CONCLUSIONS

GBP may be helpful to reduce AUD patients' heavy drinking behavior and withdrawal, but more studies are needed for drawing conclusions.

High-dose ethanol intoxication decreases 1/f neural noise or scale-free neural activity in the resting state

Binge drinking is a frequent phenomenon in many western societies and has been associated with an increased risk of developing alcohol use disorder later in life. Yet, the effects of high-dose alcohol intoxication on neurophysiological processes are still quite poorly understood. This is particularly the case given that neurophysiological brain activity not only contains recurring (oscillatory) patterns of activity, but also a significant fraction of "scale-free" or arrhythmic dynamics referred to as 1/f type activity, pink noise, or 1/f neural noise. Neurobiological considerations suggest that it should be modulated by alcohol intoxication. To investigate this assumption, we collected resting state EEG data from n = 23 healthy young male subjects in a crossover design, where each subject was once tested sober and once tested while intoxicated (mean breath alcohol concentration of 1.1 permille ±0.2). Analyses of the 1/f neural dynamics showed that ethanol intoxication decreased resting state 1/f neural noise, as compared with a sober state. The effects were strongest when the eyes were closed and particularly reliable in the beta frequency band. Given that the dynamics of the beta band have been shown to strongly depend on GABA_A receptor neural transmission, this finding nicely aligns with the fact that ethanol increases GABAergic signaling. The study reveals a currently unreported effect of binge drinking on neurophysiological dynamics, which likely revealed a higher sensitivity for ethanol effects than most commonly considered measures of power in neural oscillations. Implications and applicability of these findings are discussed.

Pharmacotherapies and personalized medicine for alcohol use disorder: a review

Alcohol use disorder (AUD) is highly prevalent and among the leading causes of morbidity and mortality in the United States. Pharmacotherapies for AUD are limited, thus making identification of patient subgroups that are most likely to respond favorably crucial. In this article, pharmacogenetic research on US FDA-approved and commonly prescribed off-label medications for the treatment of AUD is comprehensively reviewed. While the field has advanced in understanding pharmacotherapies for AUD and potential genetic moderators of treatment responses, the pharmacogenetic data to guide the prescribing clinician are limited and should be interpreted with caution. Precision medicine for AUD with more beneficial treatment responses and minimal side effects remains a high priority for further research.

Gabapentin-induced drug-seeking-like behavior: a potential role for the dopaminergic system

Drugs of abuse represent a growing public health crisis. Accumulating evidence indicates that gabapentin (GBP), a prescription drug, is prone to misuse, abuse, withdrawal, and dependence. Commonly, drugs of abuse modulate the dopaminergic system to induce addiction. In this study, we used the conditioned place preference (CPP) model to investigate the involvement of the dopamine 1 (D1) receptor on the reward and reinforcement behavior of GBP. Under a CPP paradigm, male BALB/c mice were intraperitoneally injected either saline or 100, 200, or 300 mg/kg of GBP and confined to the injection-paired chamber for 30 min. In the pre-conditioning phase, mice were conditioned for 3 days, and baseline data were collected. In the conditioning phase, mice were given once-daily alternating injections of either GBP or saline for 8 days and subsequently assessed in a post-conditioning test. Injections of 300 mg/kg of GBP significantly increased the time spent in the drug-paired chamber compared to the saline-paired chamber. However, lower doses of GBP (100 and 200 mg/kg) showed no effect. Pre-treatment with SKF-83566, a D1 receptor antagonist, attenuated GBP-induced CPP. Thus, for the first time, we show that GBP can induce CPP through a dopaminergic-dependent mechanism.

Stress Allostasis in Substance Use Disorders: Promise, Progress, and Emerging Priorities in Clinical Research

Clinicians and researchers alike have long believed that stressors play a pivotal etiologic role in risk, maintenance, and/or relapse of alcohol and other substance use disorders (SUDs). Numerous seminal and contemporary theories on SUD etiology posit that stressors may motivate drug use and that individuals who use drugs chronically may display altered responses to stressors. We use foundational basic stress biology research as a lens through which to evaluate critically the available evidence to support these key stress-SUD theses in humans. Additionally, we examine the field's success to date in targeting stressors and stress allostasis in treatments for SUDs. We conclude with our recommendations for how best to advance our understanding of the relationship between stressors and drug use, and we discuss clinical implications for treatment development.

Alcohol Rehabilitation Within 30 Days of Hospital Discharge Is Associated With Reduced Readmission, Relapse, and Death in Patients With Alcoholic Hepatitis

BACKGROUND & AIMS

Patients admitted to the hospital for alcoholic hepatitis (AH) are at increased risk of readmission and death. We aimed to identify factors associated with readmission, alcohol relapse, and mortality.

METHODS

We performed a retrospective analysis of consecutive patients admitted with AH to a tertiary care hospital from 1999 through 2016 (test cohort, n = 135). We validated our findings in a prospective analysis of patients in a multi-center AH research consortium from 2013 through 2017 (validation cohort, n = 159). Alcohol relapse was defined as any amount of alcohol consumption within 30 days after hospital discharge. Early alcohol rehabilitation was defined as residential or outpatient addiction treatment or mutual support group participation within 30 days after hospital discharge.

RESULTS

Thirty-day readmission rates were 30% in both cohorts. Alcohol relapse rates were 37% in the test and 34% in the validation cohort. Following hospital discharge, 27 patients (20%) in the test cohort and 19 patients (16%) in the validation cohort attended early alcohol rehabilitation. There were 53 deaths (39%) in a median follow-up time of 2.8 years and 42 deaths (26%) in a median follow-up time of 1.3 years, respectively. In the test cohort, early alcohol rehabilitation reduced odds for 30-day readmission (adjusted odds ratios [AOR] 0.16; 95% CI, 0.04-0.65; P = .01), 30-day alcohol relapse (AOR, 0.11; 95% CI, 0.02-0.53; P < .001), and death (adjusted hazard ratio [AHR], 0.20; 95% CI, 0.05-0.56; P = .001). In the validation cohort early alcohol rehabilitation reduced odds for 30-day readmission (AOR, 0.30; 95% CI, 0.09-0.98; P = .04), 30-day alcohol relapse (AOR 0.09; 95% CI, 0.01-0.73; P = .02), and death (AHR, 0.20; 95% CI, 0.01-0.94; P = .04). A model combining alcohol rehabilitation and bilirubin identified patients with readmission to the hospital within 30 days with an area under the receiver operating characteristic curve of 0.73.

CONCLUSIONS

In an analysis from two cohorts of patients admitted with AH, early alcohol rehabilitation can reduce risk of hospital readmission, alcohol relapse, and death and should be considered as a quality indicator in AH hospitalization treatment.

The Use of Functional Magnetic Resonance Imaging to Test Pharmacotherapies for Alcohol Use Disorder: A Systematic Review

Alcohol use disorder (AUD) is a chronic relapsing condition that represents a significant public health concern. Pharmacological treatment development for AUD is a top research priority, and many studies are being conducted to evaluate potential AUD treatments. Understanding the brain circuitry impacted by addiction is crucial for the development of efficacious pharmacological interventions. These neuroadaptations can be probed noninvasively using functional magnetic resonance neuroimaging (fMRI). fMRI may be an effective tool to identify biomarkers for AUD pharmacotherapies, evaluating changes associated with pharmacological treatment. Thus, the present qualitative review of the literature focuses on the role of fMRI as a tool for medication development for AUD. The aim of this review was to assemble research across a range of fMRI paradigms to study the effectiveness of pharmacological treatments of adult AUD. First, we present a qualitative review of fMRI AUD pharmacotherapy studies, differentiating studies based on their dosing regimen. Second, we provide recommendations for the field to improve the use of fMRI as a biomarker for AUD pharmacotherapy.

Efficacy of gabapentin in the treatment of trigeminal neuralgia: A systematic review of randomized controlled trials

The aim of this systematic review was to determine the efficacy of gabapentin (GBP) in the treatment of pain of  idiopathic trigeminal neuralgia (TN). A comprehensive literature search was conducted using the Cumulative Index of Nursing and Allied Health Literature (EBSCO Industries), Emcare (Ovid), Medline (Ovid), Medline (PubMed), Scopus (Elsevier) and Web of Science (Clarivate Analytics). The inclusion criteria comprised randomized controlled trials of GBP as a monotherapy in the treatment of idiopathic TN in adult participants and publications in English. All other study methodologies were excluded. The search yielded 1472 articles, and after exclusion, 11 full-text articles were eligible for full-text analysis. Only two studies met the inclusion criteria. There is insufficient evidence either to support or refute the efficacy of GBP in the management of idiopathic TN. Therefore, further well-designed placebo-controlled trials are required to confirm the efficacy of GBP in managing TN pain as a single therapy.

Gabapentin prescribed during substance abuse treatment: The perspective of treatment providers

BACKGROUND

Gabapentin, a prescription medication approved for the treatment of seizures and neuralgia, is often prescribed off-label for substance use treatment, mental health problems, and pain. Emerging reports also suggest it is misused for the purpose of getting high. The present study examines substance abuse treatment provider key informants' experiences with gabapentin prescribed to clients in treatment. The focus of this exploratory study is to ascertain how gabapentin is used in these settings and the benefits and risks for clients.

METHODS

Key informants from South Florida participated in confidential, in-depth interviews (N = 12). Data analyses included descriptive and in vivo coding schemes and employed a descriptive qualitative approach.

RESULTS

All key informants recognized the benefits of prescribing gabapentin to clients in treatment for problems related to withdrawal symptoms, mental distress and pain. At the same time, half of participants described gabapentin misuse among clients and four key informants described such misuse as a first marker of relapse. Key informants also stated that more research must be done about how to use gabapentin effectively in treatment settings.

CONCLUSIONS

These findings illustrate the lack of clarity about the efficacy of administration of gabapentin in treatment settings. Additional research about how to best use gabapentin, for whom it may be beneficial, and the effect of prescribed gabapentin on addiction recovery is needed.

Selecting an appropriate alcohol pharmacotherapy: review of recent findings

PURPOSE OF REVIEW

Only a few pharmacological treatments are available for treating alcohol use disorders (AUDs). Disulfiram, naltrexone and acamprosate are Food and Drug Administration (FDA)-approved and nalmefene is EMA-approved in European Union. Off-label medications, such as baclofen, gabapentin, ondansetron and topiramate are medications commonly prescribed for the treatment of AUD. The aim of this review is to give an update on recent randomized controlled trials (RCTs) and reviews evaluating pharmacological treatment for AUD.

RECENT FINDINGS

A literature search was conducted for pharmacological treatment for alcohol use disorder, published from January 2017 to January 2019. An additional search from two ongoing-study databases was performed. A total of 13 studies, 11 reviews and 7 on-going clinical trials were identified. Interest in studying baclofen as a treatment for AUD was greater compared with other medications, yet with inconclusive results. Three new RCTs of first-line medication naltrexone showed reduction in drinking.

SUMMARY

Three new published RCTs focus on baclofen and naltrexone. These results are consistent with old findings demonstrating that naltrexone reduces heavy drinking. Several RCT on baclofen do not support the use of baclofen for treatment of AUD. Encouraging results have been reported for topiramate, gabapentin and also varenicline, which might be useful in patients with comorbid nicotine dependence.

Gabapentin Enacarbil Extended-Release for Alcohol Use Disorder: A Randomized, Double-Blind, Placebo-Controlled, Multisite Trial Assessing Efficacy and Safety

BACKGROUND

Several single-site alcohol treatment clinical trials have demonstrated efficacy for immediate-release (IR) gabapentin in reducing drinking outcomes among individuals with alcohol dependence. The purpose of this study was to conduct a large, multisite clinical trial of gabapentin enacarbil extended-release (GE-XR) (HORIZANT^® ), a gabapentin prodrug formulation, to determine its safety and efficacy in treating alcohol use disorder (AUD).

METHODS

Men and women (n = 346) who met DSM-5 criteria for at least moderate AUD were recruited across 10 U.S. clinical sites. Participants received double-blind GE-XR (600 mg twice a day) or placebo and a computerized behavioral intervention (Take Control) for 6 months. Efficacy analyses were prespecified for the last 4 weeks of the treatment period.

RESULTS

The GE-XR and placebo groups did not differ significantly on the primary outcome measure, percentage of subjects with no heavy drinking days (28.3 vs. 21.5, respectively, p = 0.157). Similarly, no clinical benefit was found for other drinking measures (percent subjects abstinent, percent days abstinent, percent heavy drinking days, drinks per week, drinks per drinking day), alcohol craving, alcohol-related consequences, sleep problems, smoking, and depression/anxiety symptoms. Common side-effects were fatigue, dizziness, and somnolence. A population pharmacokinetics analysis revealed that patients had lower gabapentin exposure levels compared with those in other studies using a similar dose but for other indications.

CONCLUSIONS

Overall, GE-XR at 600 mg twice a day did not reduce alcohol consumption or craving in individuals with AUD. It is possible that, unlike the IR formulation of gabapentin, which showed efficacy in smaller Phase 2 trials at a higher dose, GE-XR is not effective in treating AUD, at least not at doses approved by the U.S. Food and Drug Administration for treating other medical conditions.

Investigational drug therapies in phase I and phase II clinical trials for alcohol use disorders

INTRODUCTION

Alcohol use disorder (AUD) is a complex psychiatric condition characterized by craving, compulsive seeking, loss of control of alcohol consumption as well as the emergence of negative emotional states during withdrawal. Despite the large socioeconomic burden of AUD, therapeutic treatment options lag behind.

AREAS COVERED

This review covers pharmacotherapies currently in phase I/II clinical trials for the treatment of AUDs listed on clinicaltrials.gov. We discuss drug therapies that modulate monoamine, GABA/Glutamate, neuropeptide and neuroimmune systems. We examine in depth preclinical and clinical evidence of a select range of these compounds and consider their utility in treating AUDs.

EXPERT OPINION

Current therapeutic options to treat AUD are inadequate at a population level. Currently there are 30 different compounds and one compound combination in phase I/II clinical trials for AUD. These compounds target various aspects of neurotransmitter signaling, neuroimmune modulation, and alcohol metabolism. Almost 75% of these compounds under trial are Food and Drug Administration (FDA) approved for other indications, which may save time and costs in treatment development. Further, development of therapeutics focused on genetic biomarkers and behavioral screening may improve how treatment decisions are made in the future on a case-by-case basis.

Gabapentin Is a Potent Activator of KCNQ3 and KCNQ5 Potassium Channels

Synthetic gabapentinoids, exemplified by gapapentin and pregabalin, are in extensive clinical use for indications including epilepsy, neuropathic pain, anxiety, and alcohol withdrawal. Their mechanisms of action are incompletely understood, but are thought to involve inhibition of α₂δ subunit-containing voltage-gated calcium channels. Here, we report that gabapentin is a potent activator of the heteromeric KCNQ2/3 voltage-gated potassium channel, the primary molecular correlate of the neuronal M-current, and also homomeric KCNQ3 and KCNQ5 channels. In contrast, the structurally related gabapentinoid, pregabalin, does not activate KCNQ2/3, and at higher concentrations (≥10 µM) is inhibitory. Gabapentin activation of KCNQ2/3 (EC₅₀ = 4.2 nM) or homomeric KCNQ3* (EC₅₀ = 5.3 nM) channels requires KCNQ3-W265, a conserved tryptophan in KCNQ3 transmembrane segment 5. Homomeric KCNQ2 or KCNQ4 channels are insensitive to gabapentin, whereas KCNQ5 is highly sensitive (EC₅₀ = 1.9 nM). Given the potent effects and the known anticonvulsant, antinociceptive, and anxiolytic effects of M-channel activation, our findings suggest the possibility of an unexpected role for M-channel activation in the mechanism of action of gabapentin.