This study examined the association of subjective responses with subsequent laboratory self-administration, also evaluating laboratory phenotypes in relation to putative genetic risk factors [family history (FH) of alcohol dependence and OPRM1 genotype] and subsequent heavy drinking.
Findings suggest no OPRM1-based susceptibility to the number of heavy-drinking peers, adding to the existing mixed findings from correlational studies.
OPRM1 genotype did not significantly moderate these effects, but G-allele carriers who received naltrexone had an accelerated return to heavy drinking after medication was stopped.