Treatment of alcohol withdrawal with gabapentin

Comparative efficacy of various pharmacologic treatments for alcohol withdrawal syndrome: a systematic review and network meta-analysis

This study was to compare multiple classes of medications and medication combinations to find alternatives or additives for patients not applicable to benzodiazepines (BZDs). We performed a network meta-analysis to assess the comparative effect of 11 pharmacologic treatments in patients with alcohol withdrawal syndrome. Forty-one studies were included, comprising a total sample size of 4187 participants. The pooled results from the randomized controlled trials showed that there was no significant difference in the Clinical Institute Withdrawal Assessment-Alcohol, revised (CIWA-Ar) reduction with other medications or medication combinations compared to BZDs. Compared to BZDs, the mean difference in ICU length of stay of anticonvulsants + BZDs was -1.71 days (95% CI = -2.82, -0.59). Efficacy rankings from cohort studies showed that anticonvulsant + BZDs were superior to other treatments in reducing CIWA-Ar scores and reducing the length of stay in the ICU. Synthesis results from randomized controlled trials indicate that there are currently no data suggesting that other medications or medication combinations can fully replace BZDs. However, synthetic results from observational studies have shown that BZDs are effective in the context of adjuvant anticonvulsant therapy, particularly with early use of gabapentin in combination with BZDs in the treatment of alcohol withdrawal syndrome, which represents a promising treatment option.

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.

Guidelines for biological treatment of substance use and related disorders, part 1: Alcoholism, first revision

These practice guidelines for the biological treatment of alcohol use disorders are an update of the first edition, published in 2008, which was developed by an international Task Force of the World Federation of Societies of Biological Psychiatry (WFSBP). For this 2016 revision, we performed a systematic review (MEDLINE/PUBMED database, Cochrane Library) of all available publications pertaining to the biological treatment of alcoholism and extracted data from national guidelines. The Task Force evaluated the identified literature with respect to the strength of evidence for the efficacy of each medication and subsequently categorised it into six levels of evidence (A-F) and five levels of recommendation (1-5). Thus, the current guidelines provide a clinically and scientifically relevant, evidence-based update of our earlier recommendations. These guidelines are intended for use by clinicians and practitioners who evaluate and treat people with alcohol use disorders and are primarily concerned with the biological treatment of adults with such disorders.

Abuse of Gabapentin is Associated with Opioid Addiction

The objective of this study was to evaluate the extent of gabapentin misuse in a dually diagnosed correctional population, and to evaluate if this abuse is specific to the presence of an opioid use disorder (OUD). Two-hundred and fifty former inmates, living in a correctional community center, who were referred for a psychiatric evaluation, were asked, through a brief written questionnaire, whether or not they used the following drugs for non-medical use in the past: opiates, gabapentin, buproprion, quetiapine, and fluoxetine. The average age of this population was 37.2 ± 12.1 years (n = 250). Sixty-four percent were male, 72 % were white, 27 % were black, and 1 % was Hispanic. All patients had substance use disorders, the large majority (72 %) to more than one substance. Fifty-eight percent had an opioid use disorder, again mostly in combination with other drugs and/or alcohol. Depressive disorders and attention deficit hyperactivity disorder were the most common psychiatric conditions. Sixty-two percent of patients reported prescription drug misuse of any kind. As expected, a high percent (55 %) reported opiate misuse. No patient reported fluoxetine misuse. Sixteen percent reported having misused gabapentin in the past. Of patients with an opioid use disorder (OUD: n = 145), 26 % endorsed gabapentin abuse while only 4 % of patients without an OUD (n = 105) endorsed the non-medical use of gabapentin. This difference was highly statistically significant (Chi square χ² = 21.6, p < 0.0001). A growing concern about gabapentin misuse was supported in this study: 26 percent of opiate addicted patients reported illegally obtaining, overusing, or malingering problems to obtain gabapentin. This study highlights the fact that gabapentin abuse appears specific to an opioid addicted population.

Treatment-refractory substance use disorder: Focus on alcohol, opioids, and cocaine

Substance use disorders are common, but only a small minority of patients receive adequate treatment. Although psychosocial therapies are effective, relapse is common. This review focusses on novel pharmacological and other treatments for patients with alcohol, opioid, or cocaine use disorders who do not respond to conventional treatments. Disulfiram, acamprosate, and the opioid antagonist naltrexone have been approved for the treatment of alcoholism. A novel, "as needed" approach is the use of the mu-opioid antagonist and partial kappa agonist nalmefene to reduce alcohol consumption. Other novel pharmacological approaches include the GABA-B receptor agonist baclofen, anticonvulsants such as topiramate and gabapentin, the partial nicotine receptor agonist varenicline, and other drugs. For opioid dependence, opioid agonist therapy with methadone or buprenorphine is the first-line treatment option. Other options include oral or depot naltrexone, morphine sulfate, depot or implant formulations, and heroin (diacetylmorphine) in treatment-refractory patients. To date, no pharmacological treatment has been approved for cocaine addiction; however, 3 potential pharmacological treatments are being studied, disulfiram, methylphenidate, and modafinil. Pharmacogenetic approaches may help to optimize treatment response in otherwise treatment-refractory patients and to identify which patients are more likely to respond to treatment, and neuromodulation techniques such as repeated transcranial magnetic stimulation and deep brain stimulation also may play a role in the treatment of substance use disorders. Although no magic bullet is in sight for treatment-refractory patients, some novel medications and brain stimulation techniques have the potential to enrich treatment options at least for some patients.

Cortical inhibition within motor and frontal regions in alcohol dependence post-detoxification: A pilot TMS-EEG study

OBJECTIVES

Preclinical studies suggest that cortical alterations within the prefrontal cortex (PFC) are critical to the pathophysiology of alcohol dependence. Combined transcranial magnetic stimulation (TMS) and electroencephalography (EEG) allows direct assessment of cortical excitability and inhibition within the PFC of human subjects. We report the first application of TMS-EEG to measure these indices within the PFC of alcohol-dependent (ALD) patients post-detoxification.

METHODS

Cortical inhibition was assessed in 12 ALD patients and 14 healthy controls through single and paired-pulse TMS paradigms. Long-interval cortical inhibition indexed cortical inhibition in the PFC. In the motor cortex (MC), short- interval intracortical inhibition and cortical silent period determined inhibition, while intracortical facilitation measured facilitation, resting and active motor threshold indexed cortical excitability.

RESULTS

ALD patients demonstrated altered cortical inhibition across the bilateral frontal cortices relative to controls. There was evidence of altered cortical excitability in ALD patients; however, no significant differences in MC inhibition.

CONCLUSIONS

Our study provides first direct evidence of reduced cortical inhibition in the PFC of ALD patients post-detoxification. Altered cortical excitability in the MC may reflect hyper-excitability within the cortex associated with chronic alcohol consumption. These findings provide initial neurophysiological evidence of disrupted cortical excitability within the PFC of ALD patients.

Are Alcohol Anti-relapsing and Alcohol Withdrawal Drugs Useful in Cannabinoid Users?

Cannabinoids are still classified as illegal psychoactive drugs despite their broad and increasingly acknowledged therapeutic potential. These substances are most famous for their wide recreational use, particularly among young adults to either alter the state of consciousness, intensify pleasure induced by other psychoactive substances or as an alternative to the previously abused drugs. It is important to emphasize that cannabinoids are often taken together with a variety of medications intended for the treatment of alcohol use disorder (AUD) or alcohol withdrawal syndrome (AWS). These medications include disulfiram, acamprosate, and naltrexone. In this paper, we summarize recent advances in the knowledge of possible beneficial effects and interactions between cannabinoids and drugs commonly used for treatment of AUD and AWS either comorbid or existing as a separate disorder.

Gabapentin Therapy in Psychiatric Disorders: A Systematic Review

OBJECTIVE

Gabapentin is commonly used off-label in the treatment of psychiatric disorders with success, failure, and controversy. A systematic review of the literature was performed to elucidate the evidence for clinical benefit of gabapentin in psychiatric disorders.

DATA SOURCES

Bibliographic reference searches for gabapentin use in psychiatric disorders were performed in PubMed and Ovid MEDLINE search engines with no language restrictions from January 1, 1983, to October 1, 2014, excluding nonhuman studies. For psychiatric references, the keywords bipolar, depression, anxiety, mood, posttraumatic stress disorder (posttraumatic stress disorder and PTSD), obsessive-compulsive disorder (obsessive-compulsive disorder and OCD), alcohol (abuse, dependence, withdraw), drug (abuse, dependence, withdraw), opioid (abuse, dependence, withdraw), cocaine (abuse, dependence, withdraw), and amphetamine (abuse, dependence, withdraw) were crossed with gabapentin OR neurontin.

STUDY SELECTION AND DATA EXTRACTION

The resulting 988 abstracts were read by 2 reviewers; references were excluded if gabapentin was not a study compound or psychiatric symptoms were not studied. The resulting references were subsequently read, reviewed, and analyzed; 219 pertinent to gabapentin use in psychiatric disorders were retained. Only 34 clinical trials investigating psychiatric disorders contained quality of evidence level II-2 or higher.

RESULTS

Gabapentin may have benefit for some anxiety disorders, although there are no studies for generalized anxiety disorder. Gabapentin has less likely benefit adjunctively for bipolar disorder. Gabapentin has clearer efficacy for alcohol craving and withdrawal symptoms and may have a role in adjunctive treatment of opioid dependence. There is no clear evidence for gabapentin therapy in depression, PTSD prevention, OCD, or other types of substance abuse. Limitations of available data include variation in dosing between studies, gabapentin as monotherapy or adjunctive treatment, and differing primary outcomes between trials.

CONCLUSIONS

Further research is required to better clarify the benefit of gabapentin in psychiatric disorders.

Alcohol Withdrawal Syndrome: Benzodiazepines and Beyond

Alcohol dependence is an increasing and pervasive problem. Alcohol withdrawal symptoms are a part of alcohol dependence syndrome and are commonly encountered in general hospital settings, in most of the departments. Alcohol withdrawal syndrome ranges from mild to severe. The severe complicated alcohol withdrawal may present with hallucinations, seizures or delirium tremens. Benzodiazepines have the largest and the best evidence base in the treatment of alcohol withdrawal, and are considered the gold standard. Others, such as anticonvulsants, barbiturates, adrenergic drugs, and GABA agonists have been tried and have evidence. Supportive care and use of vitamins is essential in the management. Symptom triggered regime is favoured over fixed tapering dose regime, although monitoring through scales is cumbersome. This article aims to review the evidence base for appropriate clinical management of the alcohol withdrawal syndrome. We searched Pubmed for articles published in English on 'Alcohol withdrawal syndrome' in humans during the last 10 years. A total of 1182 articles came up. Articles not relevant to clinical utility and management were excluded based on the titles and abstract available. Full text articles, meta-analyses, systematic reviews and randomized controlled trials were obtained from this list and were considered for review.

Identification and management of alcohol withdrawal syndrome

Symptoms of alcohol withdrawal syndrome (AWS) may develop within 6-24 h after the abrupt discontinuation or decrease of alcohol consumption. Symptoms can vary from autonomic hyperactivity and agitation to delirium tremens. The gold-standard treatment for AWS is with benzodiazepines (BZDs). Among the BZDs, different agents (i.e., long-acting or short-acting) and different regimens (front-loading, fixed-dose or symptom-triggered) may be chosen on the basis of patient characteristics. Severe withdrawal could require ICU admission and the use of barbiturates or propofol. Other drugs, such as α2-agonists (clonidine and dexmetedomidine) and β-blockers can be used as adjunctive treatments to control neuroautonomic hyperactivity. Furthermore, neuroleptic agents can help control hallucinations. Finally, other medications for the treatment for AWS have been investigated with promising results. These include carbamazepine, valproate, sodium oxybate, baclofen, gabapentin and topiramate. The usefulness of these agents are discussed.

Pregabalin reduces alcohol drinking and relapse to alcohol seeking in the rat

RATIONALE

Pregabalin (Lyrica™) is a structural analogue of γ-aminobutyric acid (GABA) approved by FDA for partial epilepsy, neuropathic pain and recently generalized anxiety disorder. While the exact cellular mechanism of action of pregabalin is still unclear, evidence from several studies suggests that it reduces excitatory neurotransmitter release and postsynaptic excitability.

OBJECTIVES

Based on these mechanisms we sought interesting to evaluate the effect of pregabalin on alcohol-abuse-related behaviours.

MATERIALS AND METHODS

For this purpose, using genetically selected alcohol-preferring Marchigian Sardinian (msP) rats, we evaluated the effect of pregabalin on alcohol drinking and relapse to alcohol seeking elicited by environmental conditioning factors or stress.

RESULTS

Our results showed that treatment with pregabalin (0, 10, 30 and 60 mg/kg) given orally selectively reduced home cage alcohol drinking in msP rat. This effect was confirmed in self-administration experiments where pregabalin (0, 10 and 30 mg/kg) significantly reduced operant responding for alcohol but not for food. Using alcohol reinstatement models we also found that pregabalin (0, 10 and 30 mg/kg) abolished seeking behaviour elicited by the pharmacological stressor yohimbine as well as cues predictive of alcohol availability.

CONCLUSIONS

Results demonstrate that pregabalin may have potential in the treatment of alcohol addiction.

Novel therapeutic strategies for alcohol and drug addiction: focus on GABA, ion channels and transcranial magnetic stimulation

Drug addiction represents a major social problem where addicts and alcoholics continue to seek and take drugs despite adverse social, personal, emotional, and legal consequences. A number of pharmacological compounds have been tested in human addicts with the goal of reducing the level or frequency of intake, but these pharmacotherapies have often been of only moderate efficacy or act in a sub-population of humans. Thus, there is a tremendous need for new therapeutic interventions to treat addiction. Here, we review recent interesting studies focusing on gamma-aminobutyric acid receptors, voltage-gated ion channels, and transcranial magnetic stimulation. Some of these treatments show considerable promise to reduce addictive behaviors, or the early clinical studies or pre-clinical rationale suggest that a promising avenue could be developed. Thus, it is likely that within a decade or so, we could have important new and effective treatments to achieve the goal of reducing the burden of human addiction and alcoholism.

Simultaneous quantification of levetiracetam and gabapentin in plasma by ultra-pressure liquid chromatography coupled with tandem mass spectrometry detection

INTRODUCTION

Gabapentin (Neurontin) and levetiracetam (Keppra) are anticonvulsants with novel structures and suggested therapeutic ranges of 2-10 mg/L and 6-20 mg/L, respectively. Gabapentin is also used extensively to manage neuropathic pain, and for this indication, wherein higher doses are prescribed, plasma concentrations of 15-30 mg/L are typical.

OBJECTIVE

Here, we describe a simple rapid assay to support therapeutic drug monitoring of gabapentin and levetiracetam in plasma by ultra-pressure liquid chromatography couples to tandem mass spectrometry (UPLC-MS/MS) detection.

METHODS

After the addition of internal standard and protein precipitation of patient plasma with methanol:acetonitrile in a 50:50 ratio, 1 μL of supernatant sample is injected onto an Acquity UPLC HSS T3, 1.8 μm, 2.1 × 50 mm (Waters) column. Elution occurs using a linear gradient of acetonitrile and water, each having 0.1% formic acid added. The column is eluted into a Waters Acquity UPLC TQD, operating in a positive mode to detect gabapentin at transition 172.18 > 154.11, levetiracetam at 171.11 > 126, and internal standard (3-amino-2-naphthoic acid) at 188.06 > 170. Secondary transitions for each analyte are also monitored for gabapentin at 172.18 > 137.06, levetiracetam at 171.11 > 154, and internal standard at 188.06 > 115. Runtime is 1.5 minutes per injection with baseline resolved chromatographic separation.

RESULTS

The analytical measurement ranges were 1-150 mg/L for gabapentin and for levetiracetam. Intra-assay imprecision by the coefficient of variance (CV) was less than 8% and interassay CV was less than 5% for both analytes, at 4 different concentrations. Results obtained from patient samples were compared with results generated by established high-performance liquid chromatography-UV methods with the following regression statistics: y = 1.12x - 0.77, r = 0.996, Sy, x = 0.89, and n = 29 for gabapentin and y = 0.991x + 0.70, r = 0.997, Sy, x = 2.24, and n = 30 for levetiracetam. No analytical interferences were identified.

CONCLUSION

: In summary, a simple reliable UPLC-MS/MS method was developed and validated for routine clinical monitoring of gabapentin and levetiracetam.

Importance of gabapentin dose in treatment of opioid withdrawal

AIM

The aim of the study was to evaluate the efficacy of gabapentin (1600 mg/d) as an adjunctive to methadone-assisted detoxification in the treatment of opioid withdrawal symptoms.

DESIGN

This was a 3-week open-label study (as second phase) following a double-blind, placebo-controlled study with 900 mg/d of gabapentin (as first phase of this study).

SETTING

The study was conducted at a specialized outpatient clinic for the treatment of patients with addictive disorders.

PARTICIPANTS

The study subjects were composed of 27 patients addicted to opiate who met the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria for opioid dependency, randomly selected among outpatients referred to our clinic.

INTERVENTION

Subjects received adjunctive treatment with gabapentin (1600 mg/d) in addition to methadone-assisted detoxification for 3 weeks.

MEASUREMENTS

Subjective Opiate Withdrawal Scale (SOWS) with a total score of 0 to 64 was administered at 6 time points during the study.

FINDINGS

The total SOWS score was significantly decreased after the intervention. Compared to our previous trial, an almost significant difference was observed in total SOWS scores between groups treated with gabapentin 1600 and 900 mg/d at the end of the intervention period (P = 0.06). Gabapentin with a dose of 1600 mg/d was significantly superior to a dose of 900 mg/d in decreasing severity of coldness, diarrhea, dysphoria, yawing, and muscle tension.

CONCLUSIONS

Add-on gabapentin with a dose of 1600 mg/d is effective in reducing some of the withdrawal symptoms in patients addicted to opiate undergoing methadone-assisted detoxification.

Glutamatergic medications for the treatment of drug and behavioral addictions

Historically, most pharmacological approaches to the treatment of addictive disorders have utilized either substitution-based methods (i.e., nicotine replacement or opioid maintenance) or have targeted monoaminergic or endogenous opioidergic neurotransmitter systems. However, substantial evidence has accumulated indicating that ligands acting on glutamatergic transmission are also of potential utility in the treatment of drug addiction, as well as various behavioral addictions such as pathological gambling. The purpose of this review is to summarize the pharmacological mechanisms of action and general clinical efficacy of glutamatergic medications that are currently approved or are being investigated for approval for the treatment of addictive disorders. Medications with effects on glutamatergic transmission that will be discussed include acamprosate, N-acetylcysteine, d-cycloserine, gabapentin, lamotrigine, memantine, modafinil, and topiramate. We conclude that manipulation of glutamatergic neurotransmission is a relatively young but promising avenue for the development of improved therapeutic agents for the treatment of drug and behavioral addictions.

Emerging drugs to treat alcoholism

IMPORTANCE OF THE FIELD

Alcoholism is a widespread disorder with substantial mortality and negative treatment outcomes. To date, few medications have been found to reduce relapse rates or drinking in alcohol-dependent patients.

AREAS COVERED IN THIS REVIEW

This review focuses on drugs that have been clinically tested for the treatment of alcohol dependence in clinical trials, pilot trials or which are considered to have a clinical perspective. For this purpose, a detailed Medline search was conducted on this issue. Although the neurochemical basis of alcoholism and the neuronal circuitry mediating its psychotropic effects have been explored in great detail in recent years, few drugs have emerged for the treatment of alcohol dependence, also because pharmaceutical companies have only a limited interest in this area of research. Acamprosate and the opioid antagonist naltrexone have been found to be effective, although data are mixed. A depot formula of naltrexone and the alternate opioid antagonist nalmefene have been studied in clinical trials and will presumably be introduced in the markets soon. Other emerging drugs are topiramate, novel acetaldehyde dehydrogenase (ALDH) inhibitors, baclofen, a combination therapy of gababentin and flumazenil and drugs targeting the cortitropin-releasing factor/neuropeptide Y mediated stress axis.

WHAT THE READER WILL GAIN

Insights on the neurochemical basis of alcohol dependence and possible targets of medications.

TAKE HOME MESSAGE

Acamprosate, naltrexone and the ALDH inhibitor disulfiram are proven medications for the treatment of alcohol dependence with modest efficacy. Novel alternate medications, a depot formulation of the opioid antagonist naltrexone and another oral opioid antagonist, nalmefene, are available now with good evidence for clinical efficacy. Novel ALDH inhibitors, antiepileptic drugs such as topiramate and drugs targeting the stress axis are currently among the most promising emerging drugs.

Pregabalin in outpatient detoxification of subjects with mild-to-moderate alcohol withdrawal syndrome

OBJECTIVE

In this open, prospective study we aimed to investigate the efficacy, medical safety and practicability of pregabalin in outpatient detoxification of alcohol-dependent patients with mild-to-moderate alcohol withdrawal syndrome (AWS). Craving reduction, improvement of psychiatric symptoms and quality of life were the secondary endpoints.

METHODS

Forty alcohol dependent patients (DSM-IV) were detoxified receiving 200-450 mg of pregabalin. Withdrawal (Clinical Institute Withdrawal Assessment for Alcohol (CIWA-Ar)) and craving (Visual Analogue Scale (VAS); Obsessive and Compulsive Drinking Scale (OCDS)) rating scales were applied; psychiatric symptoms and quality of life were evaluated using the Symptom Check List-90 Revised (SCL-90-R) and the QL-Index, respectively. Relapsed and abstinent patients in the post-detoxification evaluation have been compared.

RESULTS

Alcohol withdrawal symptoms and craving for alcohol resulted significantly reduced (p < 0.001) over time after pregabalin treatment. Pregabalin also resulted in a favourable improvement in psychiatric symptoms and quality of life (p < 0.001).

CONCLUSIONS

To our knowledge, this is the first open, prospective study, about the possible use of pregabalin as an outpatient detoxification agent. These preliminary data show its efficacy and safety in the management of patients with mild-to-moderate AWS.

Mood stabilizers in the treatment of substance use disorders

Individuals suffering from drug addiction may also manifest features of bipolar spectrum disorders. Hyperthymic and cyclothymic temperaments may render individuals vulnerable to later development of substance abuse. Bipolar disorders themselves may be altered or precipitated by substance use, most notably by stimulants (amphetamines), alcohol, and cannabinoids. The clinical usefulness of mood stabilizers, particularly antiepileptics, has been established as safe and effective in substance abusers with and without comorbid mood disorders. Most studies on this issue have been of short duration and focused on the resolution of a currently manifest period of illness. Few studies have been conducted on the usefulness of these drugs on the long-term longitudinal course of these diseases, such as frequently encountered recurrent relapses into states of agitation, impulsivity, and/or dissatisfaction. As opposed to the clinical experience with traditional antidepressants and neuroleptics, antiepileptics do not induce counter-polar states (depressed patients abruptly turning manic or hypomanic; nor patients currently hypomanic or manic turning abruptly depressed). Many clinicians consider antiepileptic mood stabilizers to be the preferred category of medications for the treatment of such patients. Valproate appears to be a potentially fruitful medication to study in these dual diagnosis patients due to preliminary evidence demonstrating its anticraving efficacy.

Efficacy of a combination of flumazenil and gabapentin in the treatment of alcohol dependence: relationship to alcohol withdrawal symptoms

Improved treatment of alcohol dependence is a high priority, including defining subtypes that might respond differently. We evaluated a medication combination of intravenous flumazenil (FMZ) and oral gabapentin (GBP) in alcoholics who did and did not exhibit pretreatment alcohol withdrawal (AW) symptoms. Sixty alcohol-dependent individuals (44 with low AW and 16 with high AW) were randomized to receive FMZ (2 mg of incremental bolus for 20 minutes for 2 consecutive days) and GBP (up to 1200 mg nightly for 39 days) or their inactive placebos. Alcohol withdrawal was measured for the first 2 days, and drinking, sleep parameters, and adverse events were monitored during weekly evaluations, along with behavioral counseling sessions. Percent days abstinent (PDA) during treatment and time to first heavy drinking (TFHD) day were primary outcome variables. There was an interaction between the pretreatment AW status and the medication group on PDA (P = 0.0006) and TFHD (P = 0.06). Those in the high AW group had more PDA and more TFHD if treated with active medications, whereas those in the low AW group had more PDA and more TFHD if treated with placebo. This interaction remained for those totally abstinent (P = 0.03) and was confirmed by percent carbohydrate-deficient transferrin values. In addition, the pattern of response remained up to 8 weeks after treatment. In addition, in those with high AW, greater improvement in AW symptoms was observed in the active medication group compared with the placebo group. These results suggest a differential response to FMZ/GBP treatment, depending on pretreatment AW status that should be taken into account during future treatment trials.

New developments for the pharmacological treatment of alcohol withdrawal syndrome. A focus on non-benzodiazepine GABAergic medications

Alcohol withdrawal syndrome (AWS) can be a life-threatening condition affecting some alcohol-dependent patients who abruptly discontinue or decrease their alcohol consumption. The main objectives of the clinical management of AWS include: to decrease the severity of symptoms, prevent more severe withdrawal clinical manifestations and facilitate entry of the patient into a treatment program in order to attempt to achieve and maintain long-term abstinence from alcohol. At present, benzodiazepines represent the drugs of choice in the treatment of AWS. However, in line with the possible side effects and addictive properties related to benzodiazepine use, there is growing evidence to suggest that non-benzodiazepine GABAergic compounds represent promising medications in the treatment of alcohol-dependent patients. This review focuses on research into non-benzodiazepine GABAergic medications for the treatment of AWS. Among them, carbamazepine, gabapentin and valproic acid are the most studied. The studies on carbamazepine seem to be the most compelling. Preliminary data have also suggested the possible utility of baclofen and topiramate, although further evidence is needed. The promising results in terms of both safety and efficacy are reported. However, we also note the need of more methodologically controlled studies on a greater number of patients, involving more complicated forms of AWS.

Cellular and behavioral interactions of gabapentin with alcohol dependence

Gabapentin is a structural analog of GABA that has anticonvulsant properties. Despite the therapeutic efficacy of gabapentin, its molecular and cellular mechanisms of action are unclear. The GABAergic system in the central nucleus of the amygdala (CeA) plays an important role in regulating voluntary ethanol intake. Here, we investigated the effect of gabapentin on GABAergic transmission in CeA slices, on ethanol intake, and on an anxiety measure using animal models of ethanol dependence. Gabapentin increased the amplitudes of evoked GABA receptor-mediated IPSCs (GABA-IPSCs) in CeA neurons from nondependent rats, but decreased their amplitudes in CeA of ethanol-dependent rats. Gabapentin effects were blocked in the presence of a specific GABA(B) receptor antagonist. The sensitivity of the GABA-IPSCs to a GABA(B) receptor antagonist and an agonist was decreased after chronic ethanol, suggesting that ethanol-induced neuroadaptations of GABA(B) receptors associated with ethanol dependence may account for the differential effects of gabapentin after chronic ethanol. Systemic gabapentin reduced ethanol intake in dependent, but not in nondependent, rats and reversed the anxiogenic-like effects of ethanol abstinence using an acute dependence model. Gabapentin infused directly into the CeA also blocked dependence-induced elevation in operant ethanol responding. Collectively, these findings show that gabapentin reverses behavioral measures of ethanol dependence and, in turn, dependence reverses the effects of gabapentin on CeA neurons, and suggest that gabapentin represents a potential medication for treatment of alcoholism.

CB1 receptor blockade reduces the anxiogenic-like response and ameliorates the neurochemical imbalances associated with alcohol withdrawal in rats

There is strong evidence that blocking CB1 receptors may reduce alcohol intake in alcohol-dependent individuals. However, there is still limited evidence that CB1 receptor antagonists may also be beneficial in the attenuation of alcohol withdrawal syndrome, even though alcohol withdrawal appears to be milder in CB1 receptor knockout mice. Here we have examined whether the CB1 receptor antagonist rimonabant (SR141716) can alleviate the behavioral symptoms and revert the neurochemical imbalance elicited by a 3-h interruption of chronic alcohol exposure (7.2% in the drinking water for 10 days) in male Wistar rats. Administration of rimonabant attenuated the strong anxiogenic traits of the animals that developed when regular alcohol intake was interrupted. This may reflect the correction of the GABA/glutamate imbalances developed by the animals that received rimonabant in various brain regions involved in emotional (e.g. prefrontal cortex) and motor (e.g. caudate-putamen and globus pallidus) responses. In addition, rimonabant also affected the dopamine deficits generated by alcohol abstinence in the amygdala and ventral-tegmental area, albeit to a lesser extent. However, this antagonist was unable to correct the impairment caused by alcohol abstinence in serotonin and neuropeptide Y. The endocannabinoid activity in the brain of alcohol-abstinent rats indicated that the behavioral and neurochemical improvements caused by rimonabant were not related to the attenuation of a possible increase in this activity generated by alcohol withdrawal. Conversely, the density of CB1 receptors was reduced in alcohol-abstinent animals (e.g. globus pallidus, substantia nigra), as were the levels of endocannabinoids and related N-acylethanolamines (e.g. amygdala, caudate-putamen). Thus, rimonabant possibly enhances an endogenous response generated by interrupting the regular use of alcohol. In summary, rimonabant might attenuate withdrawal symptoms associated with alcohol abstinence, an effect that was presumably due to the normalization of GABA and glutamate, and to a lesser extent, dopamine transmission in emotion- and motor-related areas.

Glutamatergic substrates of drug addiction and alcoholism

The past two decades have witnessed a dramatic accumulation of evidence indicating that the excitatory amino acid glutamate plays an important role in drug addiction and alcoholism. The purpose of this review is to summarize findings on glutamatergic substrates of addiction, surveying data from both human and animal studies. The effects of various drugs of abuse on glutamatergic neurotransmission are discussed, as are the effects of pharmacological or genetic manipulation of various components of glutamate transmission on drug reinforcement, conditioned reward, extinction, and relapse-like behavior. In addition, glutamatergic agents that are currently in use or are undergoing testing in clinical trials for the treatment of addiction are discussed, including acamprosate, N-acetylcysteine, modafinil, topiramate, lamotrigine, gabapentin and memantine. All drugs of abuse appear to modulate glutamatergic transmission, albeit by different mechanisms, and this modulation of glutamate transmission is believed to result in long-lasting neuroplastic changes in the brain that may contribute to the perseveration of drug-seeking behavior and drug-associated memories. In general, attenuation of glutamatergic transmission reduces drug reward, reinforcement, and relapse-like behavior. On the other hand, potentiation of glutamatergic transmission appears to facilitate the extinction of drug-seeking behavior. However, attempts at identifying genetic polymorphisms in components of glutamate transmission in humans have yielded only a limited number of candidate genes that may serve as risk factors for the development of addiction. Nonetheless, manipulation of glutamatergic neurotransmission appears to be a promising avenue of research in developing improved therapeutic agents for the treatment of drug addiction and alcoholism.

Update: new uses for lithium and anticonvulsants

Anticonvulsants are being used clinically as monotherapy and adjuncts in mental illnesses other than affective disorders. This review focuses on the literature for anticonvulsants and lithium in substance use disorders, anxiety disorders, and schizophrenia. Given the abuse potential and other difficulties with prescribing benzodiazepines for alcohol and benzodiazepine withdrawal, anticonvulsants have been considered as an alternative. Promising therapeutic effects have been demonstrated in many of the anxiety disorders, with the greatest number of trials and positive results in posttraumatic stress disorder. Although anticonvulsant and lithium augmentation for schizophrenia is common in practice and has been studied in double-blind, randomized, controlled trials, the sum of the evidence has been inconclusive.

Gabapentin's acute effect on mood profile -- a controlled study on patients with alcohol withdrawal

RATIONALE

Delayed beneficial effects of gabapentin on mood were frequently reported in various patient populations. This is the first controlled study which addressed acute effects of gabapentin on mood.

METHODS

Analysis of the German version of Profile of Mood States (POMS) throughout a randomised placebo-controlled, double-blinded study of gabapentin on acute alcohol withdrawal [Bonnet, U., Banger, M., Leweke, F.M., Specka, M., Müller, B.W., Hashemi, T., Nyhuis, P.W., Kutscher, S., Burtscheidt, W., Gastpar, M. 2003. Treatment of acute alcohol withdrawal with gabapentin -- results from a controlled two-center trial. J Clin Psychopharmacol 23, 514-519]. In addition, subjective severity of alcohol withdrawal was determined by the Essen Self-Assessment of Alcohol Withdrawal Scale (ESA) to control effects of concurrent withdrawal on POMS. Ratings were performed at intake (baseline), day 1 (study medication 400 mg q.i.d.), day 2 (study medication 400 mg q.i.d.) and day 7 (no study medication).

RESULTS

Analyses could be performed on 46 out of 59 randomised subjects. Within the first two days of the study, a significant stronger increase in the POMS-vigour subscore occurred in the gabapentin group. A subgroup analysis suggests that gabapentin's effect on vigour largely results from a stronger improvement of vigour in a small group of 11 patients with co-morbid mild depression (according to ICD-10: dysthymia or depressive adjustment disorder). There were no significant differences between the treatment groups regarding the other POMS-subscores (dejection, fatigue, anger) ruling out an overall fast effect on mood. Moreover, ESA-measures were not significantly altered indicating a missing effect of 400 mg gabapentin q.i.d. on acute alcohol withdrawal itself. After tapering off study medication, no more significant differences between gabapentin and placebo group were observed on vigour, strongly suggesting that the initial effect results from a pharmacological gabapentin action.

CONCLUSION

Gabapentin selectively accelerated the improvement of the vigour-subscore of patients with acute alcohol withdrawal within 48 h. This effect was independent from the subjective severity of withdrawal and especially marked in patients with co-morbid mild depression.

The effect of combined administration of ethanol and gabapentin on rabbit electroencephalographic activity

The central effect of ethanol is mainly connected with the effect on GABAergic, glutamatergic, serotonergic and opioid transmission. The mechanism of gabapentin effect suggests that it may alleviate the rewarding effect of ethanol, which may be used in the treatment of addiction. We decided to examine the interaction of ethanol with gabapentin by a pharmaco-electroencephalographic (EEG) method. The influence of gabapentin on the effect of ethanol on EEG of rabbits (midbrain reticular formation, hippocampus, frontal cortex) was tested. Gabapentin was administered at a single dose (25 and 100 mg/kg orally) or repeatedly twice a day at a total dose of 25 mg/kg for 14 days. Ethanol was injected at a dose of 0.8 g/kg 60 min. after gabapentin treatment. Ethanol caused an increase in the slow frequencies (0.5-4 Hz) in the recording, as well as a marked decrease of the fastest frequencies (13-30 and 30-45 Hz). Gabapentin lead to changes in rabbit EEG recording suggesting an depressant effect on the CNS (increase of slow and decrease of fast frequencies). The effects were less pronounced after repeated doses, which may indicate adaptative changes in the receptors. Gabapentin administered both in a single dose and for 7 days markedly enhanced the effect of ethanol on EEG recordings in rabbits. Repeated doses of gabapentin decrease the sensitivity of the hippocampus to the effect of ethanol.

Effect of the administration of tiagabine and gabapentin on rabbit electroencephalogram activity

New generation antiepileptic drugs, including gabapentin and tiagabine, are used in monotherapy or in combination with other drugs for specific seizure types. The multidirectional mechanism of activity and varied pharmacological properties of these drugs suggest that they could also be used in the therapy of other diseases. A possible limitation of new generation antiepileptic drugs is the incidence of CNS-related adverse effects. Few studies have assessed the effect of new antiepileptic drugs on electroencephalogram (EEG) recordings in subjects using these drugs for diseases other than epilepsy. The aim of this study was to determine the effects of tiagabine and gabapentin on EEG recordings from the midbrain reticular formation, dorsal hippocampus and frontal cortex in rabbits. Tiagabine was administered orally at a single dose of 5 and 20 mg kg(-1), or repeatedly at a dose of 5 mg kg(-1) (twice a day) for 14 days. Gabapentin was administered orally at a single dose of 25 and 100 mg kg(-1), or repeatedly at a dose of 25 mg kg(-1) (twice a day) for 14 days. Both tiagabine and gabapentin caused changes indicative of CNS inhibitory properties, which may be associated with the adverse effects of the drugs. After repeated doses of the drugs, the changes in EEG recordings were less pronounced than after single doses, which may indicate adaptive changes. The hippocampus was found to be the least sensitive to the effect of gabapentin.

An overview of medications for the treatment of alcohol withdrawal and alcohol dependence with an emphasis on the use of older and newer anticonvulsants

There is a growing interest in the development of new pharmacological tools for treating alcohol withdrawal and dependence. A number of anticonvulsants including valproate and carbamazepine have been shown to be safe and effective alternatives to benzodiazepines for treating alcohol withdrawal. These agents are relatively safe, are free from demonstrated abuse liability, and do not usually potentiate the psychomotor and cognitive effects of alcohol. For the treatment of alcohol dependence, there is a growing literature on the utility of medications that have neurochemical effects at opioid, serotonergic, GABAergic, and glutamate receptors. Furthermore, as a class of medication, there appears to be a growing interest in investigating the utility of novel anticonvulsants such as topiramate for the treatment of alcohol dependence.

Understanding and treating alcohol dependence

This article represents the proceedings of a symposium presented at the 158th Annual Meeting of the American Psychiatric Association held in Atlanta, Georgia, on May 24, 2005. The organizer/chairman was Bankole A. Johnson, DSc, MD, PhD. The presentations included the following: (1) Neuropharmacological Basis of Alcohol Dependence, by George F. Koob, PhD; (2) Recent Developments in the Genetics of Alcohol Dependence, by Marc A. Schuckit, MD; (3) New Pharmacological Strategies for Treating Alcohol Dependence, by Barbara J. Mason, PhD; (4) New Medications: The Use of Anticonvulsants, Both Alone and in Combination, with Various Forms of Psychotherapy, by Bankole A. Johnson, DSc, MD, PhD; and (5) Differential Effects of Pharmacological Agents on Craving, by Nassima Ait-Daoud, MD.

The acute effects of gabapentin in combination with alcohol in heavy drinkers

BACKGROUND

Alcohol effects in humans involve gamma-amino butyric acid (GABA) neurotransmission. It has been proposed that GABAergic medications may be effective in the treatment of alcohol dependence. This study evaluated the acute effects of gabapentin, an anticonvulsant that increases extracellular GABA, on the subjective, physiological, and performance effects of alcohol in heavy (mean 34 drinks per week) alcohol drinkers.

METHODS

Seventeen volunteers without alcohol dependence were tested using a double-blind design with three 3-day long inpatient phases, each separated by at least a 1-week wash-out period. Each phase, gabapentin (0, 1000, or 2000mg) was administered 4h before alcohol (0.75g/kg), which was given in four divided doses every 20min.

RESULTS

Gabapentin impaired the ability to balance without producing changes in subjective, physiological or other performance measures. Pretreatment with gabapentin did not significantly alter subjective and performance effects of alcohol and did not alter alcohol craving. Gabapentin, dose-dependently enhanced alcohol-induced tachycardia.

CONCLUSIONS

Acute gabapentin administration was well tolerated in combination with alcohol, but did not alter the effects of alcohol.

A Randomized, Open-Label, Controlled Trial of Gabapentin and Phenobarbital in the Treatment of Alcohol Withdrawal

Gabapentin was compared with phenobarbital for the treatment of alcohol withdrawal in a randomized, open-label, controlled trial in 27 inpatients. There were no significant differences in the proportion of treatment completers between treatment groups or the proportion of patients in each group requiring rescue medication for breakthrough signs and symptoms of alcohol withdrawal. There were no significant treatment differences in withdrawal symptoms or psychological distress, nor were there serious adverse events. These findings suggest that gabapentin may be as effective as phenobarbital in the treatment of alcohol withdrawal. Given gabapentin's favorable pharmacokinetic profile, further study of its effectiveness in treating alcohol withdrawal is warranted.

Recent advances in the development of treatments for alcohol and cocaine dependence: focus on topiramate and other modulators of GABA or glutamate function

Neuroscientific developments have promulgated interest in developing efficacious medications for the treatment of substance dependence. Previous pharmacological strategies that involve the use of relatively specific medications to alter corticomesolimbic dopaminergic neuronal activity--the critical pathway for expression of the reinforcing effects of abused drugs--have yielded modest efficacy in the treatment of alcohol dependence, and no medication has been established as a treatment for cocaine dependence. Since corticomesolimbic dopaminergic neurons interact with other neurotransmitters that modulate the effects of dopamine in the nucleus accumbens, would it not be possible to control these dopaminergic effects more reliably with a medication that acts contemporaneously on more than one neuromodulator of dopaminergic function? Further, since the long-term use of either alcohol or cocaine results in neuronal adaptations as a result of sensitisation, would the chances of effective therapy not be bolstered by administering a medication that was also able to mitigate these chronic effects? Thus, a new conceptual approach is needed. My proposal is that a medication--in this case topiramate--that principally potentiates inhibitory GABA(A) receptor-mediated input and antagonises excitatory glutamatergic afferents to the corticomesolimbic dopaminergic system should have therapeutic potential in treating either alcohol or cocaine dependence or perhaps both. This is because the principal neurochemical effects of topiramate would not only serve to decrease the acute reinforcing effects of alcohol or cocaine, but might also facilitate cessation of their use following a period of long-term use by decreasing neuronal sensitisation. This overview highlights the scientific concepts and clinical evidence for the development of topiramate in the treatment of alcohol dependence and introduces preliminary evidence to indicate that it might also have utility in treating cocaine dependence. Finally, to place the material on topiramate in context, information has been included on the utility and development of other medications that modulate GABA- or glutamate-mediated neuronal systems for the treatment of alcohol or cocaine dependence.

Update on the neurobiology of alcohol withdrawal seizures

Abrupt cessation of alcohol intake after prolonged heavy drinking may trigger alcohol withdrawal seizures. Generalized tonic-clonic seizures are the most characteristic and severe type of seizure that occur in this setting. Generalized seizures also occur in rodent models of alcohol withdrawal. In these models, the withdrawal seizures are triggered by neuronal networks in the brainstem, including the inferior colliculus; similar brainstem mechanisms may contribute to alcohol withdrawal seizures in humans. Alcohol causes intoxication through effects on diverse ion channels and neurotransmitter receptors, including GABA(A) receptors--particularly those containing delta subunits that are localized extrasynaptically and mediate tonic inhibition--and N-methyl-D-aspartate (NMDA) receptors. Alcohol dependence results from compensatory changes during prolonged alcohol exposure, including internalization of GABA(A) receptors, which allows adaptation to these effects. Withdrawal seizures are believed to reflect unmasking of these changes and may also involve specific withdrawal-induced cellular events, such as rapid increases in alpha4 subunit-containing GABA(A) receptors that confer reduced inhibitory function. Optimizing approaches to the prevention of alcohol withdrawal seizures requires an understanding of the distinct neurobiologic mechanisms that underlie these seizures.

Novel anticonvulsants in the treatment of alcoholism

There have been many recent developments in the pharmacological management of alcohol withdrawal and alcohol dependence. Although previous treatments had included benzodiazepines as their mainstay, the use of these agents in the alcoholic population is problematic. Benzodiazepines are themselves addictive and they may increase the risk of alcohol relapse. Non-benzodiazepine anticonvulsants such as carbamazepine, valproic acid, gabapentin, vigabatrin and topiramate have been shown to be excellent treatments of both alcohol withdrawal and the prevention of alcohol relapse. Although none of these agents have yet been approved by the FDA, there is growing evidence in the literature to support their use.

Safety and Efficacy of GABAergic Medications for Treating Alcoholism

This article highlights the proceedings of a symposium presented at the 27th Annual Scientific Meeting of the Research Society on Alcoholism in Vancouver, British Columbia, Canada, June 29, 2004. The organizers and co-chairs were Bankole A. Johnson, MD, PhD, and Robert M. Swift, MD, PhD. The presentations included (1) Introduction, by Bankole A. Johnson; (2) Safety, Tolerability, and Efficacy of gamma-Hydroxybutyric Acid and Baclofen in the Treatment of Alcohol Addiction, by Giovanni Addolorato; (3) Safety of Gabapentin in Treating Alcoholism, by Hugh Myrick; (4) New Data on the Safety and Effectiveness of Topiramate in the Treatment of Alcohol Dependence, by Bankole A. Johnson; (5) Evaluating the Risk of Benzodiazepine Prescription to Alcohol-Dependent Individuals, by Domenic A. Ciraulo; and (6) Safety and Efficacy of GABAergic Agents in Treating Alcoholics: Discussion, by Robert M. Swift.

Add-on gabapentin in the treatment of opiate withdrawal

Gabapentin is an antiepileptic drug shown to be effective in the treatment of pain disorders and appears to be useful as well for several psychiatric disorders, including bipolar disorder, anxiety disorders, alcohol withdrawal and cocaine dependence. Gabapentin, at a dose of 600 mg three times a day, was evaluated as an add-on medication to a standard detoxification regime in seven heroin dependent individuals undergoing outpatient opiate withdrawal treatment. All seven patients successfully completed opiate detoxification and commenced opiate antagonist treatment with naltrexone on day five of withdrawal treatment, as scheduled. No adverse event was noted. Gabapentin appeared to lead a reduction in symptomatic medication and an overall beneficial effect on symptoms of heroin withdrawal.

Treatment of acute alcohol withdrawal with gabapentin: results from a controlled two-center trial

A few case reports and data from animal experiments point to a possible efficacy of gabapentin (GP) in the treatment of alcohol withdrawal syndrome (AWS). Because of ethical considerations, the efficacy of GP in acute AWS was tested in an add-on fashion to clomethiazole (CLO). Given that the symptom-triggered amount of CLO required to limit AWS within the first 24 hours is related to the severity of AWS, we tested this amount of CLO during placebo (P) or GP (400 mg qid) under double blind, randomized conditions. Sixty-one patients (P = 29/GP = 32) suffering from alcohol dependence (ICD-10) and without any other psychiatric condition or psychotropic medication were included. The groups were not significantly different in baseline characteristics (eg, demographic data, severity of AWS). Both ITT and completer analyses revealed no significant differences between the groups considering the primary effectiveness measure: amount of CLO required in the first 24 hours (P = 6.1 +/- 5.4/GP = 6.2 +/- 4.7 capsules). In addition, premature discontinuations (P = 3/GP = 2) and decreases in Mainz Alcohol Withdrawal Scores were not significantly different in the first 48 hours of AWS (secondary effectiveness measures). Tolerability of combined CLO/GP was studied throughout the whole treatment comprising a 5-day lasting reduction part subsequent to the first 48 hours. Throughout the whole 7-day treatment a total of 5 and 2 patients dropped out and 6 and 5 patients reported adverse clinical events in the P and GP groups, respectively. All together, GP (400 mg qid) was no better than P in saving initial consumption of CLO or decreasing initial Mainz Alcohol Withdrawal Scores suggesting that GP was ineffective in the management of acute AWS in this model. The combination of GP and CLO was safe.

Gabapentin for the treatment of ethanol withdrawal

Benzodiazepines (BZDs) are the drug of choice for the suppression of alcohol withdrawal symptoms. Gabapentin, a drug approved for use as adjunctive therapy in the treatment of partial seizures, has none of the BZD-type difficulties (drug interactions, abuse potential). We retrospectively report on the use of gabapentin for ethanol withdrawal in 49 patients. Thirty-one patients were treated in the outpatient program and 18 in the general inpatient psychiatric unit. Positive outcomes as evidenced by completion of gabapentin therapy were achieved in 25 out of 31 outpatients and 17 out of 18 inpatients. Statistical significance was reached regarding the positive relationship between prior ethanol use and inpatient "as needed" benzodiazepine use. Both sets of data suggest that gabapentin works well for the mild to moderate alcohol withdrawal patient.