Pharmacotherapies for alcoholism: promising agents and clinical issues

Combined fluoxetine and disulfiram treatment of alcoholism with comorbid affective disorders. A naturalistic outcome study, including quality of life measurements

This uncontrolled study presents 188 patients primarily diagnosed as addictive alcoholics and fulfilling the DSM III diagnostic criteria for panic disorder or major depression, 104 and 84 patients, respectively. The study focused on clinical outcome of pharmacological intervention with combined fluoxetine and disulfiram treatment. The patients were followed for (up to) 40 months. A good clinical outcome for both groups was found in 70%. In a subgroup of 37 patients ‘quality of life’ was assessed using quality of life scales. An appropriate correlation emerged between clinical judgement of outcome and the patients’ self-rating. Although the study was limited by being uncontrolled, the results have shown, that specific treatment in a group of alcoholics with comorbid psychopathology within the anxiety and depression spectrum is possible even after many years of addictive alcohol abuse. The necessity for proper psychiatric assessment is stressed.

Perspectives on the neuroscience of alcohol from the National Institute on Alcohol Abuse and Alcoholism

Mounting evidence over the last 40 years clearly indicates that alcoholism (alcohol dependence) is a disorder of the brain. The National Institute on Alcohol Abuse and Alcoholism (NIAAA) has taken significant steps to advance research into the neuroscience of alcohol. The Division of Neuroscience and Behavior (DNB) was formed within NIAAA in 2002 to oversee, fund, and direct all research areas that examine the effects of alcohol on the brain, the genetic underpinnings of alcohol dependence, the neuroadaptations resulting from excessive alcohol consumption, advanced behavioral models of the various stages of the addiction cycle, and preclinical medications development. This research portfolio has produced important discoveries in the etiology, treatment, and prevention of alcohol abuse and dependence. Several of these salient discoveries are highlighted and future areas of neuroscience research on alcohol are presented.

Medications development to treat alcohol dependence: a vision for the next decade

More than 76 million people world-wide are estimated to have diagnosable alcohol use disorders (AUDs) (alcohol abuse or dependence), making these disorders a major global health problem. Pharmacotherapy offers promising means for treating AUDs, and significant progress has been made in the past 20 years. The US Food and Drug Administration approved three of the four medications for alcoholism in the last two decades. Unfortunately, these medications do not work for everyone, prompting the need for a personalized approach to optimize clinical benefit or more efficacious medications that can treat a wider range of patients, or both. To promote global health, the potential reorganization of the National Institutes of Health (NIH) must continue to support the National Institute on Alcohol Abuse and Alcoholism's (NIAAA's) vision of ensuring the development and delivery of new and more efficacious medications to treat AUDs in the coming decade. To achieve this objective, the NIAAA Medications Development Team has identified three fundamental long-range goals: (1) to make the drug development process more efficient; (2) to identify more efficacious medications, personalize treatment approaches, or both; and (3) to facilitate the implementation and adaptation of medications in real-world treatment settings. These goals will be carried out through seven key objectives. This paper describes those objectives in terms of rationale and strategy. Successful implementation of these objectives will result in the development of more efficacious and safe medications, provide a greater selection of therapy options and ultimately lessen the impact of this devastating disorder.

Effects of Atypical Anxiolytic N-Phenyl-2-[1-[3-(2-Pyridinylethynyl)Benzoyl]-4-Piperidine]Acetamide (JNJ-5234801) on Alcohol Intake in Alcohol-Preferring P Rats

BACKGROUND

N-Phenyl-2-[1-[3-(2-pyridinylethynyl)benzoyl]-4-piperidine]acetamide (JNJ-5234801) is a structurally novel atypical anxiolytic with an overall in vivo profile in animals suggestive of the potential to show anxiolytic efficacy in humans at doses that will not cause CNS-related side effects. Furthermore, unlike the benzodiazepines, JNJ-5234801 does not have an adverse interaction with ethanol even at doses 20 to 40 times the minimal effective dose in the rat elevated plus maze (MED=1.0 mg/kg, p.o.).

METHODS

In the present study, JNJ-5234801 was evaluated for potential efficacy in reducing alcohol intake in alcohol-preferring rats. Alcohol-preferring P rats were allowed to drink water or alcohol (10%, v/v) in a 2-bottle choice procedure. Once stable baselines were established, the acute effects of JNJ-5234801 [(10-40 mg/kg, intraperitoneally (i.p.)] were assessed. In a separate study, chronic treatment with JNJ-5234801 (40 mg/kg once daily, i.p.) for 12 consecutive days was compared with naltrexone (20 mg/kg, twice daily, i.p.).

RESULTS

There was a selective dose-dependent reduction in alcohol intake in the alcohol-preferring (P) rats after acute administration of JNJ-5234801 (10-40 mg/kg, i.p.). There were no significant effects on food or water intake. When administered subchronically, both JNJ-5234801 (40 mg/kg once daily, i.p.) and naltrexone (20 mg/kg, twice daily, i.p.) considerably reduced alcohol intake, but tolerance to the alcohol-suppressing effects appeared to occur sooner in the naltrexone-treated group. While both compounds slightly but significantly reduced food intake at the beginning, only JNJ-5234801 increased water intake and decreased alcohol preference.

CONCLUSIONS

The novel atypical anxiolytic JNJ-5234801 has a favorable profile effects on alcohol intake and related measures compared with naltrexone, which is recommended for the treatment of alcoholism.

Use of a novel mouse genotype to model acute benzodiazepine withdrawal

Withdrawal from benzodiazepines in physically dependent rodents often requires that the drug be dislodged from its receptor with a competitive antagonist. Withdrawal Seizure-Prone (WSP) mice were selectively bred for their susceptibility to handling-induced withdrawal convulsions following chronic treatment with ethanol. Reflecting pleiotropic genetic influences, they also experience more severe withdrawal from other sedative-hypnotics including the benzodiazepine, diazepam. We used this susceptible genotype to test whether other benzodiazepine receptor (BZR) agonists also produce physical dependence following acute administration, comparing studies of spontaneous withdrawal with those where convulsions were precipitated by a BZR antagonist (flumazenil). Separate groups of mice were tested following a single injection of one of eight BZR agonists. Several doses of each drug were tested for spontaneous withdrawal, and a single dose of each drug was tested for precipitated withdrawal. Withdrawal convulsions were seen after all of the drugs by at least one method, suggesting that BZR agonists as a class elicit acute physical dependence in this susceptible genotype.

Oxcarbazepine versus carbamazepine in the treatment of alcohol withdrawal

In a single-blinded and randomized pilot study efficacy and tolerability of oxcarbazepine versus carbamazepine were investigated in 29 patients during therapy of alcohol withdrawal. No initial differences were found regarding sociodemographic data and alcohol-related parameters, indicating successful randomization. The oxcarbazepine group showed a significant decrease of withdrawal symptoms and reported significantly less 'craving for alcohol' compared to the carbamazepine group. Subjectively experienced side effects, normalization of vegetative parameters and improvement in the cognitive processing speed did not reveal differences for both groups. Therefore, oxcarbazepine might be an interesting alternative to carbamazepine, and having almost no addictive potential, no clinically relevant interaction with alcohol and no prominent sedatory effect, possibly also to other drugs such as benzodiazepines or clomethiazole, in the treatment of alcohol withdrawal syndrome.

An extract of the Chinese herbal root kudzu reduces alcohol drinking by heavy drinkers in a naturalistic setting

BACKGROUND

Of the available medications for treating alcohol-related problems, none are universally effective, and all have side effects that may limit their use. Extracts of kudzu containing a variety of isoflavones have been shown to reduce alcohol drinking in rats and hamsters.

METHODS

The present study was designed to test the efficacy of a kudzu extract in a clinical population. Male and female "heavy" alcohol drinkers were treated with either placebo or a kudzu extract for 7 days and then given an opportunity to drink their preferred brand of beer while in a naturalistic laboratory setting. Participants served as their own controls, and order of treatment exposure was counterbalanced. Drinking behavior was monitored by a digital scale that was located in the top of an end table.

RESULTS

Kudzu treatment resulted in significant reduction in the number of beers consumed that was paralleled by an increase in the number of sips and the time to consume each beer and a decrease in the volume of each sip. These changes occurred in the absence of a significant effect on the urge to drink alcohol. There were no reported side effects of kudzu treatment.

CONCLUSION

These data suggest that an extract of this leguminous plant may be a useful adjunct in reducing alcohol intake in a naturalistic setting.

Effects of acute alcohol withdrawal on memory performance in alcohol-dependent patients: a pilot study

Studies on the neuropsychological performance in detoxified alcoholic patients often begin by acknowledging that there is a cognitive impairment to be found. Only little attention has been paid to date to the question as to how acute alcohol withdrawal might affect cognitive functions. Twenty-nine alcohol-dependent inpatients, nine in moderate alcohol withdrawal, treated with carbamazepine (group 1), 10 in mild alcohol withdrawal without pharmacological treatment (group 2), 10 in mild alcohol withdrawal with carbamazepine treatment (group 3) and 31 healthy subjects as controls (group 4) underwent repeated investigations using memory tests. The tests were performed on the first, third, seventh and fourteenth days of withdrawal. Immediate free recall of a word-list was impaired in the three patient groups in comparison with the control group on the 1st day. Thereafter no significant differences could be revealed between patients and controls. In a word-list recognition test the memory functions were not impaired in group 1 and group 2 in comparison with the control subjects. However, patients in group 3 showed impairment in this recognition test in comparison with the healthy subjects on the first and third days. The present study suggests that acute alcohol withdrawal impairs memory functions, especially free recall. This should be considered in treatment interventions in the early days of withdrawal.

A large randomized placebo controlled study of auricular acupuncture for alcohol dependence

We report clinical data on the efficacy of acupuncture for alcohol dependence. 503 patients whose primary substance of abuse was alcohol participated in this randomized, single blind, placebo controlled trial. Patients were assigned to either specific acupuncture, nonspecific acupuncture, symptom based acupuncture or convention treatment alone. Alcohol use was assessed, along with depression, anxiety, functional status, and preference for therapy. This article will focus on results pertaining to alcohol use. Significant improvement was shown on nearly all measures. There were few differences associated with treatment assignment and there were no treatment differences on alcohol use measures, although 49% of subjects reported acupuncture reduced their desire for alcohol. The placebo and preference for treatment measures did not materially effect the results. Generally, acupuncture was not found to make a significant contribution over and above that achieved by conventional treatment alone in reduction of alcohol use.

Alcoholism: beliefs and attitudes among Canadian alcoholism treatment practitioners

OBJECTIVES

To explore differences in views concerning adjunctive medications and theoretical orientation among Canadian practitioners from different professional backgrounds who treat alcoholism.

METHODS

A survey of clinicians from different disciplines was conducted by mail. The response rate was 56%: 95 drug and alcohol counsellors, 46 social workers, 81 nonpsychiatrist addiction physicians, and 74 addiction psychiatrists. The number of items in the questionnaire was reduced using principal component analysis. Group differences were explored using analysis of variance with Bonferroni correction and Scheffé's posthoc comparisons.

RESULTS

Physicians and nonphysicians differed in their views on the utility of medications in treating alcohol problems, the disease concept of alcohol problems, and the classification of alcohol abuse or dependence as psychiatric conditions. No group differences emerged on views regarding cognitive-behavioural treatment, pharmacological-only interventions, combined treatment, and recovery without treatment. Psychopathology in the alcoholic was significantly more likely to be considered as secondary to the use of alcohol by nonpsychiatrist physicians. Nonphysician practitioners viewed alcoholic behaviour as self-medication.

CONCLUSIONS

Groups differed on questionnaire items concerning medication use and the disease concept of alcoholism. Agreement on several areas may facilitate bridging the gap across disciplines. The implications of these results are discussed.

Abecarnil and alprazolam reverse anxiety-like behaviors induced by ethanol withdrawal

This study investigated the effects of a benzodiazepine partial agonist, abecarnil, and a full agonist, alprazolam, on ethanol withdrawal-induced anxiety-like behaviors in rats. Anxiety was assessed in two models: elevated plus maze and pentylenetetrazol (GABA(A) antagonist) discrimination assay. Male rats received an ethanol-containing (4.5%) liquid diet for 7 to 10 days and were tested for withdrawal symptoms 12 h after termination of the diet. In the elevated plus maze, ethanol-withdrawn rats displayed less open arm activity and total arm entries than pair-fed rats. Abecarnil (0.08-0.32 mg/kg, IP) and alprazolam (0.08-1.25 mg/kg, IP) each produced a dose-dependent, full reversal of ethanol withdrawal-induced reduction of open arm activity, but only alprazolam increased the total arm entries. In the pentylenetetrazol assay, ethanol-withdrawn rats selected the pentylenetetrazol lever (100%) over the salin-lever. Abecarnil (0.04-0.32 mg/kg, IP) and alprazolam (0.08-0.32 mg/kg, IP) dose dependently reduced pentylenetetrazol-lever responding to control levels (10-20%). Alprazolam was more potent than abecarnil in reversing ethanol withdrawal-induced decrease in open arm activities, but showed comparable potency and efficacy to abecarnil in blocking the pentylenetetrazol-like ethanol withdrawal stimulus. These results suggest that abecarnil and alprazolam may have therapeutic potential for treatment of ethanol withdrawal-induced anxiety-like symptoms.

Opioid antagonists and alcoholism treatment

The increasing evidence for a neurobiologic basis for alcoholism has spurred the search for pharmacologic agents to treat alcohol abuse. The complex set of symptoms and behaviors that characterizes alcoholism has been linked to dopaminergic and opioid neurotransmitter systems, suggesting that opioid antagonists, such as naltrexone, may alter the positive reinforcement effects and craving involved in alcoholism. Laboratory and clinical investigations of naltrexone have demonstrated the potential for this agent to reduce craving, increase the aversive effects of alcohol, decrease drinking days, and increase abstinence. While naltrexone and other opioid antagonists, such as nalmefene, may be effective components of an alcohol-treatment program, they should only be used in combination with psychosocial interventions, such as support groups and psychotherapy.

Thiamin deficiency and Korsakoff's syndrome: failure to find memory impairments following nonalcoholic Wernicke's encephalopathy

Prolonged alcohol consumption is associated with a variety of neuropsychiatric conditions, including the dense amnesic disorder known as Korsakoff's syndrome. Korsakoff's syndrome is frequently diagnosed in alcoholics after an episode of acute thiamin deficiency. The accepted view within the medical literature is that the etiology of this disorder lies in thiamin deficiency or Wernicke's encephalopathy. However, examination of the published reports of pure thiamin deficiency unaccompanied by chronic and excessive consumption of alcohol shows that, in this group of patients, the rate of progression to Korsakoff's syndrome is low. This result suggests that the memory impairments associated with alcohol-related brain damage cannot be attributed to thiamin deficiency alone. The etiology of alcohol-related cognitive impairments such as Korsakoff's syndrome is still poorly understood but several lines of evidence suggest multiple causal factors interact to produce deficits in performance. Animal models that manipulate only a single putative etiological factor are unlikely to elucidate the multiple influences that lead to Korsakoff's syndrome. A study of the natural history of alcohol-related brain damage is needed that will allow an assessment of individual risk factors and their interactions.

Genetic determinants of severity of acute withdrawal from diazepam in mice: commonality with ethanol and pentobarbital

Potentially life-threatening seizures can occur following withdrawal from benzodiazepines, ethanol, or barbiturates. In animals, withdrawal severity has been shown to be partially genetically determined for each drug class. Susceptibility to these drugs is partially determined by common genetic factors, but the evidence is conflicting. We tested the hypothesis that acute benzodiazepine withdrawal convulsions are influenced by at least some genes that also affect withdrawal from ethanol and pentobarbital. Results in inbred mouse strains demonstrate that strain susceptibility is genetically correlated with susceptibility to ethanol and pentobarbital. The proportion of variance accounted for by genetic factors common to diazepam and ethanol was estimated at 69%. Results contrast with previous data obtained in mice that were serially tested for withdrawal severity from ethanol, pentobarbital, and then diazepam, because serial testing of mice significantly affected the previous results for some strains. Diazepam withdrawal severity was also genetically correlated with pentobarbital withdrawal. Together, these results suggest that some genes influence severity of withdrawal from several types of depressant drugs.

Lorazepam for the prevention of recurrent seizures related to alcohol

BACKGROUND AND METHODS

Alcohol abuse is one of the most common causes of seizures in adults. In a randomized, double-blind study, we compared lorazepam with placebo for the prevention of recurrent seizures related to alcohol. Over a 21-month period, we studied consecutive patients with chronic alcohol abuse who were at least 21 years of age and who presented to the emergency departments of two hospitals in Boston after a witnessed, generalized seizure. The patients were randomly assigned to receive either 2 mg of lorazepam in 2 ml of normal saline or 4 ml of normal saline intravenously and then observed for six hours. The primary end point was the occurrence of a second seizure during the observation period.

RESULTS

Of the 229 patients who were initially evaluated, 186 met the entry criteria. In the lorazepam group, 3 of 100 patients (3 percent) had a second seizure, as compared with 21 of 86 patients (24 percent) in the placebo group (odds ratio for seizure with the use of placebo, 10.4; 95 percent confidence interval, 3.6 to 30.2; P<0.001). Forty-two percent of the placebo group were admitted to the hospital, as compared with 29 percent of the lorazepam group (odds ratio for admission, 2.1; 95 percent confidence interval, 1.1 to 4.0; P=0.02). Seven patients in the placebo group and one in the lorazepam group were transported to an emergency department in Boston with a second seizure within 48 hours after hospital discharge.

CONCLUSIONS

Treatment with intravenous lorazepam is associated with a significant reduction in the risk of recurrent seizures related to alcohol.

Alcoholic patients' experience and attitudes on pharmacotherapy for alcoholism

Clinical studies have demonstrated that pharmacotherapies may improve alcoholism treatment, when combined with traditional psychosocial therapies. Recently, the opioid antagonist, naltrexone, has been approved as an adjunct in alcoholism treatment, and several other pharmacotherapies for alcoholism are under development. Because of the abstinence orientation of many patients, we assessed attitudes regarding medications, and explored whether alcoholic patients would consider taking medication as part of their alcoholism treatment. Active patients (n = 127) in three alcohol treatment settings were surveyed with an anonymous questionnaire which asked demographics, personal alcoholism history and questions about medication use. They were asked whether they felt disulfiram and naltrexone were helpful for alcoholics and whether they would take the medications. The findings indicate that the patients were divided about the use of pharmacotherapy for the treatment of alcoholism. The strongest predictor of willingness to take medication was a belief that the medication would be helpful.

Pharmacological treatment of alcoholism

1. Pharmacological treatments are effective as part of a treatment plan that includes substantial education, psychological therapy and social support. This paper reviews recent literature on animal models of and treatment for alcohol abuse under seven categories: agents to block craving or reduce alcohol intake, agents to induce aversion to alcohol, agents to treat acute alcohol withdrawal, agents to treat protracted alcohol withdrawal, agents to diminish drinking by treating associated psychiatric pathology, agents to decrease drinking by treating associated drug abuse, and agents to induce sobriety in intoxicated individuals. 2. The benzodiazepines provide safe and effective treatment for detoxification, although current research focuses on finding drugs with a smaller likelihood of dependence. As yet, there are no drugs that effectively reverse the intoxicating effects of alcohol. 3. Currently, only two major groups of drugs that are relatively safe have shown any effect at reducing alcohol consumption: aversives such as disulfiram, and opioid antagonists such as naltrexone. 4. Finally, it is important to customize therapy for each patient rather than putting everyone through a standard treatment plan, especially in regards to the use of antidepressant or antipsychotic medications. Tailoring the program to the patient's needs dramatically improves the outcome of therapy and reduces the risk of adverse effects.

The role of N-methyl-D-aspartate (NMDA) receptor-mediated neurotransmission in the pathophysiology and therapeutics of psychiatric syndromes

The study of excitatory amino acids (EAAs) has recently resulted in new and fundamental concepts in neuroscience. This progress has led to a growing awareness of the crucial role that brain EAAs systems play in a variety of physiological and pathological processes. The N-methyl-D-aspartate (NMDA) receptor, presently the most well understood subtype of EAAs receptors, has been implicated in crucial physiological processes such as synaptogenesis, learning and memory. Dysfunctions of NMDA receptors seem to play a crucial role in the neurobiology of disorders such as Parkinson's disease, Alzheimer's disease, epilepsy and ischemic stroke. This paper is a review of emerging data indicating that alterations of NMDA receptor function may be pivotal to the pathophysiology of four common psychiatric syndromes: schizophrenia, major depression, posttraumatic stress disorder, and alcoholism. Special emphasis is placed on the current state of development of pharmacological strategies aiming at the modulation of NMDA receptor-mediated neurotransmission in these disorders.

The role of glutamatergic neurotransmission in the pathophysiology of alcoholism

Recent evidence suggests that ethanol abuse produces its diverse effects on the brain to a substantial degree by disrupting the function of the major excitatory neurotransmitter, glutamate. Ethanol, at concentrations associated with behavioral effects in humans, inhibits the N-methyl-D-aspartate (NMDA) receptor, which mediates the post-synaptic excitatory effects of glutamate. Tolerance to ethanol results in up-regulation of the NMDA receptor so that abrupt withdrawal produces a hyperexcitable state that leads to seizures, delerium tremens, and excitotoxic neuronal death. Ethanol's inhibition of the NMDA receptor in the fetal brain likely contributes to the CNS manifestations of fetal alcohol syndrome. Therapeutic strategies aimed at correcting glutamatergic dysregulation in alcoholism need to be explored.

Rapid increase in basal acetylcholine release in the hippocampus of freely moving rats induced by withdrawal from long-term ethanol intoxication

The effect of ethanol withdrawal on hippocampal acetylcholine (ACh) release was investigated by brain microdialysis in rats rendered ethanol dependent by repeated forced administration of a 20% ethanol solution for 7 days. The behavioral signs of ethanol withdrawal were accompanied by an increase in hippocampal ACh output that was significantly 6 h after the last ethanol administration, reached a maximum (fourfold) at 12 h, and persisted for >72 h. Administration of diazepam (5 mg/kg, i.p.) or gamma-hydroxybutyrate (1 g/kg, intragastric) 12 h after the last ethanol administration completely antagonized, within 30 min, the increase in ACh output induced by ethanol withdrawal. Thus, the rapid and marked increase in ACh output might contribute to the changes in cognitive function associated with ethanol withdrawal, and the septohippocampal cholinergic system may play a major role in the response to withdrawal of addictive drugs.

Overview of substance abuse acupuncture treatment research

The research on the efficacy of acupuncture substance abuse treatment is generally still in an early stage. The methodological weaknesses found in the acupuncture research can be found in most substance abuse research. Sufficient early trial, empirical findings suggest that there are positive treatment effects. Certainly, use of the treatment is popular and widespread. Overall, the research has progressed beyond early clinical trials, and the method has been documented to be safe and potentially useful.

Dexmedetomidine alleviates ethanol withdrawal symptoms in the rat

The effect of dexmedetomidine, a selective alpha 2-adrenoceptor agonist, on ethanol withdrawal symptoms was studied in chronically ethanol-fed rats. After a 4-day ethanol intoxication period the rats were given s.c. injections of dexmedetomidine (3, 10, or 30 micrograms/kg) or saline (control group) at 10, 16, 22, and 39 h after the last dose of ethanol. The severity of ethanol withdrawal symptoms (rigidity, tremor, irritability, hypoactivity) was rated up to 58 h, blind to the treatments. The results showed that dexmedetomidine at doses 10 and 30 micrograms/kg significantly diminished the severity of the ethanol withdrawal reaction as measured by the sum score of the three most specific withdrawal signs (rigidity, tremor, and irritability). Dexmedetomidine at 10 micrograms/kg was the most effective dose, especially in the latter half of the withdrawal period (23-58 h after last dose of ethanol). The results suggest that dexmedetomidine in the treatment of ethanol withdrawal symptoms should be further studied.

Dosing issues in the pharmacotherapy of alcoholism

Pharmacological treatments for alcohol dependence have focused increasingly on agents that reduce alcohol craving and consumption or that treat psychiatric disorders associated with drinking relapse. Clinicians who treat alcohol-dependent patients must find the optimal dose of these agents to maximize response. Determining the best dosing strategy has been the goal of recent treatment studies with alcohol-dependent patients. One study, for example, showed that an opiate antagonist medication had a dose-dependent relationship with patient outcome and retention in treatment. Another dosing consideration involves the effect of long-term alcohol abuse on drug metabolism (e.g., when treating alcohol-dependent patients for comorbid psychiatric disorders). This was demonstrated in a study of recently abstinent patients who were taking the antidepressant desipramine for major depression. Alcohol-dependent patients had higher hepatic enzyme activities and lower plasma levels of desipramine relative to oral dose than did a comparison group of depressed patients without an alcohol use disorder.

Pharmacotherapies for alcohol problems: a review of research with focus on developments since 1991

Research on medications to treat alcohol problems has flourished in the last 5 years. Whereas before this time most projects focused on withdrawal agents, at least equal interest has now extended to drugs that may directly reduce urge to drink. The most promising medications in this regard are the opiate antagonists and acamprosate. Considerable attention has also been devoted to serotonergic agents. As aids to detoxification, pharmacologic agents that affect the multiple neural systems disrupted by acute alcohol withdrawal remain under active investigation. Significant progress is also being made in identifying medications to assist alcoholics suffering collateral psychopathology, especially depression and anxiety based disorders. Unfortunately, fewer gains have been realized in the development of medications to assist patients simultaneously dependent on both alcohol and illicit drugs. Also, research to develop amethystic agents remains in its very early stages.

Naltrexone increases the latency to drink alcohol in social drinkers

We investigated the effects of naltrexone (NTX) on alcohol drinking, urge to drink alcohol, and alcohol-induced sensations and mood states in social drinkers consuming alcohol ad libitum in a cocktail bar. Sixteen college-age men and women participated in a double-blind, placebo-controlled, within-subjects, cross-over study. Subjects were tested during each of three drug conditions: NTX, 50 mg/ day, po; inactive placebo; and no drug. Each treatment condition lasted 8 to 11 days. Small groups of subjects consumed alcohol ad libitum during three 2-hr evening drinking sessions, separated by approximately-2 weeks. NTX treatment significantly increased the latency (time in seconds) to first sip the first (p < 0.05) and second alcoholic beverages consumed (p < 0.01). Moreover, the mean blood alcohol concentration at the end of the session was significantly lower when subjects were treated with NTX (p < 0.05). No differences were found on self-report urge to drink alcohol. Subjects reported more fatigue and tension on the Profile of Mood States (p < 0.05), before drinking, and increases in nausea on the Alcohol Sensation Scale (p < 0.05) when treated with NTX. The increase in the latency to sip the first and second alcoholic beverages may reflect the capacity of NTX to block urge for alcohol elicited from external cues (before consuming alcohol), as well as urge for alcohol after priming from ingested alcohol. Thus, the effectiveness of NTX for reducing drinking behaviors of alcoholics may be partially caused by anticraving properties of NTX.

Platelet adenylyl cyclase activity in alcoholics and subtypes of alcoholics. WHO/ISBRA Study Clinical Centers

Adenylyl cyclase (AC) activity was measured in membrane preparations of platelets from control and alcoholic subjects. The sample consisted of 51 alcoholics who were categorized as type I or type II using the criteria of Gilligan et al. (Genet. Epidemiol. 4:395-414, 1987) and 54 normal controls. Alcoholic males exhibited significantly lower values than controls in basal and fluoride-stimulated platelet AC activity. When male alcoholics were segregated into type I and type II categories, the platelet AC activity did not differ between subtypes, and both subtypes had AC activity that was below control values. Western blot analysis of the quantity of Gs alpha and Gi alpha proteins in a subset of male controls and alcoholic subjects demonstrated no significant relationship between quantity of G proteins and AC activity. The results confirm lower platelet AC activity in male alcoholics, compared with controls. Given the lack of quantitative relations between Gs alpha and Gi alpha proteins and AC activity, the results support the contention that individual differences in platelet AC activity in the alcoholic subjects may reflect quantitative or qualitative differences in the AC catalytic units.

A placebo-controlled, double-blind study of fluoxetine in severe alcohol dependence: adjunctive pharmacotherapy during and after inpatient treatment

Twenty-eight male patients with severe alcohol dependence (mean pretreatment consumption of 18.6 standard drinks per day) completed a placebo-controlled, double-blind clinical trial of fluoxetine (60 mg/day). They were assigned to medication group in the second of 4 weeks on a voluntary inpatient chemical dependency ward and continued medication during a 12-week follow-up phase. Fluoxetine did not reduce clinically significant relapse rates; only 8 of 15 (53%) of fluoxetine subjects remained sober at 12 weeks, compared with 9 of 13 (69%) of the placebo group (Fisher's exact test, p = 0.46). Subjects with comorbid cocaine dependence relapsed more than twice as often (3 of 4, 75%) as those with alcohol dependence alone (8 of 24, 33%), although this trend did not reach statistical significance because of the small number of dually dependent subjects (Mann Whitney U test = 68, p = 0.13). Supportive living arrangements after hospital discharge did reduce relapse rates: 8 of 9 subjects (89%) discharged to a Veterans Affairs domiciliary were sober at 12 weeks, compared with 9 of 19 (47%) subjects discharged back to the community (Mann-Whitney U test = 125, p = 0.02). Fluoxetine-treated subjects who remained sober at 12 weeks reported a significant decrease in mean subjective alcohol craving scores from 2.9 to 0.7 on a 10-point scale (t = 2.828, p = 0.02). In summary, fluoxetine did not reduce clinical relapse rates in this sample of male severe alcoholics without other axis I disorders who completed 4 weeks of inpatient alcoholism treatment.

Buspirone in the treatment of alcohol dependence: a placebo-controlled trial

A double-blind controlled study of the effects of buspirone on alcohol dependence and associated symptoms in ambulatory alcoholics showed a marked improvement in both treatment and control groups. However, significant differences in favor of the medication were observed in several psychopathological measures, but not in measures of alcohol consumption. Contrary to a majority of prior controlled trials of buspirone in alcoholics, subjects were not selected on the basis of comorbid generalized anxiety; rather, the study tested the hypothesis of a direct effect on craving and consumption, independent from an anxiolytic effect. This hypothesis was not confirmed.

Voice of the victims

Over the past 10 years, I have been privileged to conduct educational forums for audiences containing many recovering alcoholics or otherwise chemically dependent persons. In these forums about the addictive diseases and their treatment and research possibilities, significant interaction with the audience members occurs. During these interactions, certain anecdotal phenomena seem to predominate. The repetitive nature of these reports suggests the need for systematic investigation. As with editorial comments in major medical journals, observed phenomena and unanswered questions from the victims can be valuable in the generation of testable hypotheses. Perhaps the ideas presented herein will be useful in the development of future research on alcohol abuse and alcohol dependence.

Prevention of ethanol-induced sympathetic overactivity and degeneration by dexmedetomidine

The effects of dexmedetomidine, a selective alpha 2-adrenoceptor agonist, on rat sympathetic neurons were studied during a 12-day, heavy ethanol exposure. Adult male Wistar rats were given ethanol or isocaloric sucrose three times a day by intragastric intubation. Both acute (a single dose of 300 micrograms/kg p.o.) and chronic (100 micrograms/kg x 2 P.O. throughout the experiment) effects of dexmedetomidine were tested. The superior cervical ganglia (SCG) of the ethanol-exposed, non-dexmedetomidine-treated rats showed an abnormally high overall level of tyrosine hydroxylase immunoreactivity (TH-IR) and catecholamine histofluorescence. However, a subpopulation of neurons had apparently lost their catecholamine synthetic activity, as they exhibited no TH-IR or catecholamine fluorescence. The ethanol-exposed ganglia also showed structural alterations (e.g., decreased neuronal size and increased occurrence of vacuolated neurons). In the ethanol-exposed, chronically dexmedetomidine-treated group, by contrast, the SCG exhibited TH-IR and catecholamine fluorescence intensities comparable to those seen in the control ganglia. All the structural parameters studied, as well, were at the control level in the chronically dexmedetomidine-treated group. The single dose of dexmedetomidine offered only marginal protection against the ethanol-induced alterations. These results suggest that chronic dexmedetomidine treatment may prevent ethanol-induced overactivity and degeneration of catecholaminergic neurons.

A double-blind, placebo-controlled study of nortriptyline and bromocriptine in male alcoholics subtyped by comorbid psychiatric disorders

This double-blind, placebo-controlled, 6-month follow-up treatment study investigated the efficacy of bromocriptine and nortriptyline in attenuating drinking behavior and psychiatric symptoms in 216 male alcoholic patients subtyped by comorbid psychiatric disorder(s). Three well-defined subtypes were examined: alcoholism only, alcoholism + affective/anxiety disorder, and alcoholism + antisocial personality disorder. It was hypothesized that both medications would relieve negative affective symptoms associated with alcohol use and would be particularly effective for the affective/anxiety subgroup. Contrary to our predictions, the only significant effects found were with the antisocial personality disorder patients who were receiving nortriptyline. One interpretation of the results was that nortriptyline may have reduced impulsive drinking in the antisocial personality disorder subgroup by actions on serotonergic neurotransmission.

Cross-tolerance to ethanol and gamma-hydroxybutyric acid

In the present study, the development of tolerance to the motor impairing effects of gamma-hydroxybutyric acid (GHBA) and ethanol was compared (Experiment 1). Rats were required to perform a motor coordination task daily shortly after ethanol (3.5 g/kg) and GHBA (1.0 g/kg) administration for 9 consecutive days. Tolerance to the motor impairing effects of ethanol and GHBA developed to a similar extent but with different patterns. On the tenth day, the presence of cross-tolerance to the motor impairing effects of GHBA and ethanol was assessed (Experiment 2). Administration of 1.0 g/kg GHBA produced a significantly lower impairment in ethanol-tolerant rats than in ethanol-naive rats. Similarly, administration of 3.5 g/kg ethanol induced a significantly lower impairment in GHBA-tolerant rats than in GHBA-naive rats. The presence of cross-tolerance between GHBA and ethanol is discussed in terms of common pathways of neuroadaptation to chronic GHBA and ethanol.

New drugs for the treatment of experimental alcoholism

This article presents a current overview of the efforts to suppress pharmacologically the craving, dependence, or other factors associated with the self-selection of alcohol in an experimental animal. The contemporary status of the pharmacotherapy of experimental alcoholism similarly is described for different animal models of alcohol drinking. An evaluation is presented of several classes of drug for their efficacy in ameliorating the volitional ingestion of alcohol in the presence of an alternative fluid. Currently, two main experimental animal models of alcoholism are being used in this endeavor: (a) genetic lines or substrains of high alcohol preferring or high drinking rats; and (b) strains of nondrinking or low alcohol preferring rats which are induced chemically to prefer alcohol. Because of technical, methodological, and other issues surrounding the procedures used to assess the efficacy of a drug in reducing alcohol intake, several of the newer findings remain controversial. For example, serious side effects on the intake of food, caloric regulation, motor activity, or other functions would preclude the clinical utility of the drug. However, several drugs which affect monoaminergic neurons as well as opioid systems in the brain now seem to offer promise as agents which do possess clinical benefits. Two of these drugs, FG5606 (amperozide) and FG 5893 are essentially "antialcoholic" or anticraving and are without any significant side effects on cerebral mechanisms responsible for hunger, caloric intake, motor activity, or other physiological process. Amperozide, a 5-HT2 receptor antagonist with dopamine releasing properties, is particularly notable because of its irreversible nature in attenuating alcohol preference for months after its administration. It is concluded that future pharmacological research on presently available and newly developed compounds will provide exciting opportunities to the clinician who can utilize a particular drug as an adjunctive tool in the therapeutic treatment of the alcoholic individual.

Clinical predictors of alcohol withdrawal delirium

Up to now, clinical predictors for the course of the alcohol withdrawal syndrome, especially for the occurrence of a delirium, are lacking. Thus, this study was undertaken to examine whether clinical routine investigations at admission before the withdrawal syndrome can reveal factors indicating a higher risk for the development of a delirium. Our results showed that decreased serum electrolyte concentrations (i.e., chloride and potassium), elevated ALT, and gamma-glutamyltransferase serum levels, as well as ataxia and polyneuropathy at the neurological examination, indicate a higher risk for the development of an alcohol withdrawal delirium.

Therapeutic lessons from traditional Oriental medicine to contemporary Occidental pharmacology

An extract of Radix Puerariae (RP), an herb long used in traditional Chinese medicine for alcohol addiction and intoxication, was shown to suppress the free-choice ethanol intake of ethanol-preferring Syrian golden hamsters. Two isoflavones, diadzein (4',7-dihydroxyisoflavone) and daidzin (7-glucoside of daidzein), isolated from the extract were shown to account for this effect. Daidzin administered intraperitoneally at 150 mg/kg/day suppressed free-choice ethanol intake by > or = 50%. Such effect has been confirmed in a total of 79 consecutive hamsters studied over a period of more than a year. Daidzein was less potent and a higher dose (230 mg/kg/day) was required to produce similar effect. RP-, daidzin-, and daidzein-treated hamsters appeared to remain healthy and exhibited no significant change in body weight and water or food intake. In vitro, daidzin and daidzein inhibited human mitochondrial aldehyde dehydrogenase (ALDH-2) and gamma gamma-alcohol dehydrogenase (gamma gamma-ADH), respectively. However, at doses that suppressed ethanol intake, daidzin and daidzein had no effect on overall acetaldehyde and ethanol metabolism in hamsters. These findings clearly distinguish the action(s) of daidzin and daidzein from those of the classic, broad acting inhibitors of ALDH (e.g. disulfiram) and class I ADH isozymes (e.g. 4-methylpyrazole), and identify them as a new class of compounds that offer promise as safe and effective therapeutic agents for alcohol abuse.

The role of the NMDA receptor in ethanol withdrawal

The function of the N-methyl-D-aspartate (NMDA) subtype of glutamate receptor is very sensitive to acute inhibition by ethanol. Because of the role of this receptor in processes such as synaptic plasticity and neuronal development, it may contribute to the acute cognitive deficits caused by ethanol, or to the deleterious effects of ethanol during gestation. Excessive stimulation of the NMDA receptor is believed to be involved in the generation of epileptiform seizure activity as well as in excitotoxic cell death. Our studies have demonstrated that there is an adaptive "up-regulation" of NMDA receptor function in brains of chronically ethanol-treated animals and in cultured cells that have been exposed chronically to ethanol. This up-regulation appears to contribute to ethanol withdrawal seizure activity, since withdrawal seizures can be attenuated by specific NMDA receptor antagonists, and the time course of the change in receptor number parallels the time course of withdrawal seizures. In addition, cells exposed chronically to ethanol are significantly more susceptible to glutamate-induced cell death, which is mediated by the NMDA receptor, indicating a key role of the NMDA receptor in the well-characterized neuronal damage that is observed after chronic ethanol exposure and withdrawal in animals and humans. Understanding the basis for withdrawal seizures and withdrawal-induced neurotoxicity provides for the development of specific and selective therapeutic agents to ameliorate these consequences of chronic ethanol exposure and withdrawal.