Quetiapine improves response inhibition in alcohol dependent patients: a placebo-controlled pilot study

Rationale

Quetiapine has been shown to be a promising medication for the treatment of alcoholism. As an atypical antipsychotic medication with antagonist activity at D1 and D2, 5-HT_1A and 5-HT_2A, H₁ and α1 and α2 receptors, quetiapine has been found to decrease impulsivity in other psychiatric disorders but its effects on impulsivity have not been studied in alcohol dependent patients.

Objective

This study seeks to test the effects of quetiapine on a specific dimension of impulsivity, namely response inhibition. This pilot study seeks to further elucidate the mechanisms of action of quetiapine for alcohol use disorders.

Method

A total of 20 non-treatment seeking alcohol dependent individuals were randomized to one of the following conditions in a double-blind, placebo-controlled design: (1) quetiapine (400 mg/day); or (2) matched placebo. Participants completed two counterbalanced intravenous placebo-alcohol administration sessions as well as behavioral measure of response inhibition (i.e. stop signal task) pre and post placebo-alcohol administration sessions.

Results

Analyses revealed a significant effect of quetiapine in improving response inhibition as measured by the stop signal task. These results provide preliminary evidence suggesting that quetiapine improves response inhibition in alcohol dependent patients, as compared to placebo.

Conclusion

This pilot study contributes a novel putative mechanism of action of quetiapine in alcoholism, namely an improvement in response inhibition.