Pharmacotherapy of chronic alcoholism: a review

Although alcohol has been recognized as an agent of abuse since the 17th century, the disease model was accepted only in the last century. Alcoholism is defined as a chronic and progressive disease characterized by loss of control over the use of alcohol with subsequent social, legal, psychological and ethical consequences. Recently, monoamines were shown to have a predominant role in the etiology of alcoholism. Dopamine has been implicated by virtue of its actions on the reward center. Endogenous opioids which lessen stress and produce euphoria, are released upon alcohol intake, whereas increased serotonin facilitates tolerance and thereby fosters increased alcohol consumption. Alcohol has facilitative effects on inhibitory action of GABA, while the stimulatory effects of glutamate are decreased. Drugs used for treatment of alcohol dependence can be broadly classified into 4 groups: sensitizing drugs, opioid antagonists, drugs acting on serotonergic systems and acamprosate. Disulfiram has been shown to be most effective for patients who believe in its efficacy and remain compliant with the treatment. The opioid antagonist naltrexone lowers relapse rate, reduces drinking days and prolongs periods of abstinence, while serotonin reuptake inhibitors and serotonin antagonists at best have equivocal efficacy. Acamprosate restores the normal activity of glutamate and GABA systems. The treatment of alcoholism should not be restricted to pharmacotherapy alone but should also be supplemented with interventions addressing the psychological, medical and social needs of patients.