An herbal supplement made from kudzu, a plant long used in traditional medicine from East Asia, may offer a new way to help people cut back on binge drinking, according to a UC San Francisco study.
Researchers found that people with alcohol use disorder who took kudzu when they expected they might drink heavily had fewer binge-drinking days than those who received a placebo. The benefits were still evident after three months, when the treatment had ended.
Binge drinking is a major public health problem, accounting for more than half of the roughly 80,000 annual U.S. deaths attributed to excessive alcohol consumption. Yet fewer than 10% of people with alcohol use disorder have ever received medication to treat it.
Binge drinking is incredibly common, but we don't have many tools to offer people who want to cut back. Our goal is to expand that toolkit. What'sexciting about this approach is that people can use it when they know they may be at risk of heavy drinking, rather than taking a medication every day."
Glenn-Milo Santos, PhD, MPH, study's lead author and UCSF professor of community health systems
The study, published in the American Journal of Psychiatry on Nov. 4, included 120 adults with alcohol use disorder who binge drank at least once a week. For men, binge drinking was defined as having five or more drinks on one occasion, and for women, it was four or more.
Half the participants received a standardized kudzu extract and half received a placebo. For 12 weeks, they were instructed to take the treatment about 2.5 hours before they expected to drink heavily. Both groups also received brief weekly counseling sessions.
By the end of treatment, the average number of binge-drinking days had fallen from 2.15 to 1.42 per week in the kudzu group. They hardly changed in the placebo group, going from 2.15 to 2.06. Moreover, the proportion of weeks in which participants reported any binge drinking also declined markedly in the kudzu group, from 88% to 58%, compared with a much smaller change in the placebo group, from 88% to just 81%.
Three months after treatment stopped, people assigned to take kudzu continued to have significantly fewer binge-drinking days than those who were assigned to get the placebo. Researchers said reducing alcohol use during treatment may have helped participants rethink their relationship with alcohol and build confidence in their ability to drink less.
The participants tolerated taking kudzu and had no more side effects than those in the placebo group. Nor were any serious side effects linked to the treatment.
Researchers caution that consumers should not assume commercially available kudzu supplements will produce the same results. The study used a standardized formulation, while over-the-counter products can vary. Larger studies are needed to confirm the findings in broader populations.
Source:
Journal reference:
Santos, G.-M., et al. (2026). Targeted Use of Kudzu for Binge Drinking Among Adults With Alcohol Use Disorder: A Phase 2b Randomized Trial. American Journal of Psychiatry. DOI: 10.1176/appi.ajp.20251354. https://psychiatryonline.org/doi/10.1176/appi.ajp.20251354