Colin MacKenzie M.D.
December 4, 2020




Alcohol use disorder (AUD) is a chronic, relapsing disorder in which the individual cannot reduce the problematic drinking behavior despite harmful social, physical, and occupational consequences. Chronic, heavy drinking can lead to withdrawal symptoms.  Those with particularly severe alcohol withdrawal symptoms often have difficult post-withdrawal abstinence periods marked by anxiety, mood lability, and cravings, making it more difficult to stop alcohol use and placing the individual at an increased risk of relapse.  Some research has shown that many individuals with AUD who are in the early abstinence phase demonstrate disruptions in stress physiology linked to particular areas of the brain.  The end result being a reduced ability of the alcoholic individual to tolerate stressors and regulate stress responses predisposing them to seek alcohol as a means to cope and thus relapse. 

A study published in the American Journal of Psychiatry in November, 2020, examined whether a medication typically used to control hypertension called prazosin could reduce autonomic hyperactivity associated with acute and chronic alcohol withdrawal and lead to a reduction in problematic drinking. Sinha and colleagues sought to determine the efficacy of prazosin in controlling stress-induced alcohol-seeking behavior in patients with AUD who were seeking abstinence. In an attempt to demonstrate prazosin efficacy, they hypothesized that those with significant alcohol withdrawal symptoms would have a greater response to the medication in the post-acute withdrawal period than those with only mild or no withdrawal symptoms. 


A total of 112 participants diagnosed with alcohol dependence were included in the study.  The group demonstrated a range of alcohol withdrawal symptoms. The participants were randomly divided into two groups; one that received treatment with prazosin and the other that received placebo. The study duration was 12 weeks during which time the participants were assessed twice weekly for vitals, daily alcohol intake, alcohol craving, depression, anxiety, sleep quality, and alcohol withdrawal symptoms.


The group participants given prazosin and who also experienced severe alcohol withdrawal symptoms reported significantly reduced daily drinking frequency and a reduced number of daily and heavy drinking days. Individuals who experienced severe withdrawal symptoms, but received the placebo, reported comparatively higher drinking frequency along with an increased number of daily and heavy drinking days. These results indicate that alcohol withdrawal symptoms work as moderators for determining interventional efficacy.


The study findings suggest that prazosin effectively controls drinking outcomes in patients who experience severe alcohol withdrawal symptoms and is beneficial in reducing anxiety, depressed mood, and alcohol craving in such patients throughout the treatment duration. The patients with fewer alcohol withdrawal symptoms showed no improvement in drinking behavior and other outcomes with prazosin treatment. Thus, the presence of severe alcohol withdrawal symptoms serves as an important indicator of the efficacy of prazosin in treating patients with alcohol use disorder (AUD) and is most practically used in those who have experienced severe withdrawal episodes. 

Sinha, R., Wemm, S., Fogelman, N., Milivojevic, V., Morgan, P. M., Angarita, G. A. Fox, H. C. Moderation of Prazosin’s Efficacy by Alcohol Withdrawal Symptoms. American Journal of Psychiatry, appi.ajp.2020.2. doi:10.1176/appi.ajp.2020.20050609