Reference: Am J Psychiatry. 2022 Dec 1;179(12):915-926
Practice Point: Consider prn naltrexone 50 mg to curb binge drinking in patients with mild-to-moderate alcohol use disorder.
EBM Pearl: Studies of alcohol use (and other substance use) are often subject to recall bias.
Whether it’s a cultural shift or a pendulum swing in response to pandemic drinking, more American adults are reexamining their relationship with alcohol. Alcohol use and particularly binge drinking is associated with a higher risk of STDs, violence, trauma, arrhythmias, and mental health concerns. Alcohol use disorder (AUD) is one of the most prevalent substance use disorders and though medication has been shown to be effective for severe AUD, evidence for more mild subtypes is minimal. One first-line agent is naltrexone, an opioid antagonist which works by reducing the euphoric effects of alcohol and disrupting the feedback loops that can lead to excessive drinking. Though largely underutilized, daily dosing of naltrexone has been shown to reduce heavy drinking in adults with alcohol dependence or severe AUD. Problematic drinking however, is certainly not exclusive to those who meet criteria for severe AUD.
A recent study published in the American Journal of Psychiatry evaluated prn naltrexone for mild to moderate AUD in sexual and gender minority men (SGM). This population includes men who have sex with men and transgender men, and has a high prevalence of binge drinking. Investigators randomized 120 SGM (median age 37) with mild to moderate AUD and binge drinking to naltrexone 50 mg by mouth prn or matching placebo. Participants were instructed to take 1 tablet once daily for alcohol cravings or in anticipation of heavy drinking. All participants received weekly medication management and alcohol use counseling. Medication use was self-reported but verified by a cap monitor which recorded each time the pill bottle was opened. Alcohol consumption was similarly self-reported and roughly verified with weekly alcohol biomarkers (urine ethyl glucuronide and dried blood phosphatidylethanol). At 12 weeks, intention-to-treat analysis showed significant reductions in the number of drinks per month, number of binge drinking days, weeks with any binge drinking, and alcohol craving scores in the naltrexone group compared to placebo. At 6 months, treatment effects were sustained. There were no significant differences in biomarkers (as a measure of abstinence) or risky sexual behaviors between the groups. No serious adverse events occurred due to naltrexone and the most common side effect was nausea. Of note, opioid use but not other recreational drug use was an exclusion criteria for this trial.
If you have patients who enjoy a glass of wine or cocktail but are concerned about it leading to an all-night bender, prn naltrexone may be an option. Like most studies of alcohol use, the results are subject to recall bias as people are generally unreliable when it comes to calculating their intake. There was no significant difference in alcohol biomarkers between groups, which may at first seem like discordance between reporting of alcohol use and the biomarkers as an outcome measure. However, these biomarkers really only assess for presence or absence of alcohol use, and both groups were drinking. Biomarkers may be used to corroborate a given participant’s report and have been shown to improve truth in reporting. Adherence to prn medication can also be subject to recall bias but this was offset with computerized pill bottle caps. These results support prn naltrexone as an important tool to help moderate binge drinking in those with mild to moderate AUD — whether the goal is sobriety or simply moderation.
For more information, see the topic Alcohol Use Disorder in DynaMed.
DynaMed EBM Focus Editorial Team
This EBM Focus was written by Nicole Jensen, MD, Family Physician at WholeHealth Medical. Edited by Alan Ehrlich, MD, Executive Editor at DynaMed and Associate Professor in Family Medicine at the University of Massachusetts Medical School; Katharine DeGeorge, MD, MS, Deputy Editor at DynaMed and Associate Professor of Family Medicine at the University of Virginia; Dan Randall, MD, Deputy Editor at DynaMed; Vincent Lemaitre, PhD, Senior Medical Writer at DynaMed; and Sarah Hill, MSc, Associate Editor at DynaMed.