Various types of alcoholics have been described and heredity has been shown to be involved in some of these types. An important role of the mesolimbic dopamine system has been suggested in the reinforcing effects of alcohol and recent molecular genetic studies are implicating the gene for the D2 dopamine receptor (DRD2) in alcoholism. In a double-blind study, bromocriptine, a DRD2 agonist, or placebo was administered to alcoholics with either the A1 (A1/A1 and A1/A2 genotypes) or only the A2 (A2/A2 genotype) allele of the DRD2 gene. The greatest improvement in craving and anxiety occurred in the bromocriptine-treated A1 alcoholics and attrition was highest in the placebo-treated A1 alcoholics. The feasibility of a pharmacogenetic approach in treating certain types of alcoholics is suggested.