Neuropeptides and alcohol addiction in monkeys

Examining naltrexone and alcohol effects in a minority population: results from an initial human laboratory study

Prior clinical findings have indicated a potential lack of naltrexone efficacy among African Americans with alcohol dependence. However, no definitive conclusions have been drawn due to the relatively small numbers of African Americans in most alcohol treatment trials. The purpose of this study was to examine alcohol and naltrexone effects on healthy African-American individuals in a laboratory environment. Nonalcohol-dependent social drinking adults of African descent (n = 43) were recruited for participation. After consenting and completing the baseline assessment, they participated in four separate alcohol challenge sessions each separated by at least 10 days. During each of the sessions, subjects were administered alcohol or sham drinks, after pretreatment with either naltrexone (50 mg/day) or placebo in a double-blind fashion. The order of the four sessions was randomly assigned. During each session, breath alcohol levels and subjective responses were measured. Results indicate an alcohol effect among these subjects for subjective responses, but no naltrexone effect. Similar to the apparent lack of clinical efficacy findings, naltrexone does not appear to impact alcohol effects in African-American social drinkers. Future studies should investigate African-American populations with heavy drinking as well as alcohol-dependent subjects in order to strengthen the parallels to clinical findings.

Update on neuropharmacological treatments for alcoholism: scientific basis and clinical findings

The past decade has seen an expansion of research and knowledge on pharmacotherapy for the treatment of alcohol dependence. The Food and Drug Administration (FDA)-approved medications naltrexone and acamprosate have shown mixed results in clinical trials. Oral naltrexone and naltrexone depot formulations have generally demonstrated efficacy at treating alcohol dependence, but their treatment effect size is small, and more research is needed to compare the effects of different doses on drinking outcome. Acamprosate has demonstrated efficacy for treating alcohol dependence in European trials, but with a small effect size. In U.S. trials, acamprosate has not proved to be efficacious. Research continues to explore which types of alcohol-dependent individual would benefit the most from treatment with naltrexone or acamprosate. The combination of the two medications demonstrated efficacy for treating alcohol dependence in one European study but not in a multi-site U.S. study. Another FDA-approved medication, disulfiram, is an aversive agent that does not diminish craving for alcohol. Disulfiram is most effective when given to those who are highly compliant or who are receiving their medication under supervision. Of the non-approved medications, topiramate is among the most promising, with a medium effect size in clinical trials. Another promising medication, baclofen, has shown efficacy in small trials. Serotonergic agents such as selective serotonin reuptake inhibitors and the serotonin-3 receptor antagonist, ondansetron, appear to be efficacious only among certain genetic subtypes of alcoholic. As neuroscientific research progresses, other promising medications, as well as medication combinations, for treating alcohol dependence continue to be explored.

VOLUME INTAKE AND CRAVING IN ALCOHOL WITHDRAWAL

AIMS

It has been shown that beer consumption is associated with alcohol craving, in contrast to wine or spirits consumption. The present study was undertaken to evaluate whether the daily volume intake of alcoholic beverages is associated with craving in patients undergoing alcohol withdrawal.

METHODS

A total of 158 male patients were assessed using the obsessive compulsive drinking scale (OCDS) at admission. The daily volume intake of alcoholic beverages was calculated by adding the volume of all regularly consumed alcoholic beverages, disregarding their alcohol percentage. Lesch's typology was used to classify patients for subgroup analysis.

RESULTS

The daily volume intake of alcoholic beverages correlated significantly with the extent of the OCDS (r = 0.33; P < 0.001). With general linear models, we found a significant association of the calculated daily volume intake of all alcoholic beverages with craving (F = 6.426; P = 0.012), but not for the daily ethanol intake. Differentiating the patients according to Lesch's typology a significant association was particularly found in Lesch Type 2 (model of anxiety) patients (F = 11.31; P = 0.001).

CONCLUSION

Our results support the hypothesis that volume intake is associated with craving and suggest a role of pathophysiological changes in volume regulating mechanisms (such as vasopressin or ANP) in the neurobiology of alcohol craving, particularly in male patients of Lesch's Type 2 undergoing alcohol withdrawal.