REVIEW OF: Simpson TL et al, Am J Psych 2018; https://doi.org/10.1176/appi.ajp.2018.17080913

TYPE OF STUDY: Randomized, placebo-controlled trial

Prazosin is often used as a second-line option for a broad array of psychiatric conditions, including anxiety, insomnia, nightmares, and post-traumatic stress dis­order (PTSD). It is a high blood pressure medication that also modulates the stress-response system through noradrenergic effects, blocking alpha-1 receptors in the brain. Since stress is a common trigger for excessive drinking, this study set out to test whether prazosin could improve so­briety in alcohol use disorders.

Eighty subjects with alcohol use disorders were randomized to receive either prazosin or placebo. Subjects with PTSD were excluded in order to isolate the potential benefits of prazo­sin for drinking directly. Prazosin was titrated up to a target dosage of 16 mg/ day, as tolerated. All subjects were ac­tively drinking at the start of the study, and they reported their daily alcohol consumption and cravings for the pre­vious day through a toll-free interactive voice system during the 12-week study. Assessments were double-blind, and the primary outcomes were: (1) number of drinks per week, (2) number of drink­ing days per week, and (3) number of heavy drinking days per week.

Compared to placebo, those re­ceiving prazosin reported fewer drinks (mean decrease of 8.0 vs 1.5 drinks per week; p = 0.03) and fewer number of heavy drinking days (mean decrease of 0.8 vs 0.3 days per week; p = 0.01), though the number of drinking days was no less with prazosin. Drowsiness and edema were the only two side ef­fects associated with prazosin.

TCPR’S Take
Given its relatively benign side effect pro­file and established track record, prazosin can already be considered a reasonable second-line option for alcohol use disor­ders. For patients with any combination of anxiety, insomnia, nightmares, PTSD, or hypertension, prazosin is an even more appealing option.