Background

Naltrexone is an efficacious medication for the treatment of alcohol use disorder in adults. As an opioid receptor antagonist, naltrexone blocks activation of the endogenous opioid system, which is involved in the affectively reinforcing properties of substance use. Few studies, however, have examined the moderating effect of naltrexone on the association of affect and alcohol use. Additionally, most existing research on naltrexone studied adults in the human laboratory.

Method

We conducted a secondary analysis of ecological momentary assessment data from a randomized, double-blinded, placebo-controlled cross-over study, comparing naltrexone (50 mg/daily) and placebo in 26 adolescents (15–19 years old) exhibiting problematic drinking patterns. Multilevel models tested whether naltrexone moderated associations of alcohol use with both positive and negative affect (PA, NA).

Results

Results indicated that, during the naltrexone arm, greater estimated blood alcohol concentration (eBAC) levels were associated with greater NA further into drinking episodes. In turn, greater NA after the first drink of an episode was associated with reduced subsequent eBAC values in the naltrexone arm. Low PA was also associated with lower subsequent eBAC levels in the naltrexone condition after the first drink.

Conclusions

Findings support the idea that naltrexone can disrupt the association of affect and alcohol use, and these effects emerge later in drinking episodes. Greater attention to the effects of naltrexone on affect and reinforcement may help us to better tailor psychotherapy to maximize the benefits of naltrexone. However, as most drink reports were in the first two hours of the drinking episode and participants only reported affect at the first three end-drink reports of a drinking episode (limiting the number of drinks reported), replication of the findings is needed.