Efficacy of Prazosin in Treating Alcohol Use Disorder

According to a recent study published in the Journal of Addiction Medicine, prazosin might not be an effective option for treating patients with alcohol use disorder, but it could help decrease the number of drinks per week in those who can tolerate the drug.

In this 45-day, randomized, placebo-controlled clinical trial, researchers randomly assigned 36 patients (mean age, 39.6 years) with alcohol use disorder into either an intervention or placebo group.

Participants were required to be English-speaking and treatment seeking, have at least 4 heavy drinking days in the last month, and meet criteria for alcohol dependence in the last 3 months.

Both groups received treatment over the course of 8 visits spanning 6 weeks, and were evaluated at 2-week intervals for reduction in alcohol use (drinks per week and drinks per day), as well as several secondary outcomes including effects of medication on past week anxiety and diastolic blood pressure.

On the basis of the 27 individuals who completed all study visits, researchers found no significant differences between the placebo and intervention groups in regard to rate of change for all primary and secondary variables. However, post hoc analyses did demonstrate a significant “uptick” in drinks per week for participants in the optimal treatment exposure subgroup (those who completed the study and fully tolerated the medication), particularly in the periods of 2 to 4 and 4 to 6 weeks (P =.002).

Furthermore, researchers determined that participants who received prazosin and had high diastolic blood pressure (P =.013) experienced a greater rate of reduction in drinking compared with placebo participants who had high but not low blood pressure. Thus, the researchers concluded, “the effect of condition on rate of change in [drinks per week] was not moderated by [diastolic blood pressure], nor was either [drinks per drinking day] or [drinks per week] moderated by anxiety.”

Researchers noted several limitations to their study, including its small and inadequately varied sample, as well as a relatively short treatment period.

Because of these and other limitations, researchers said of their results, “Future work should explore whether these findings are replicated in a larger sample and explore the diagnostic utility (sensitivity and specificity) of [diastolic blood pressure] for predicting response to treatment with this medication class.”

Reference

Wilcox C, Tonigan S, Bogenschutz Mp, Clifford J, Bigelow R, Simpson T. A randomized, placebo-controlled, clinical trial of prazosin for the treatment of alcohol use disorder [published online April 16, 2018]. J Addict Med. doi: 10.1097/ADM.0000000000000413