UCSF trial: A kudzu plant extract taken before drinking cut binge-drinking days, but store-bought supplements may not work the same
The benefit lasted three months after people stopped taking it. Researchers say larger studies are needed.
An herbal extract made from kudzu, a vine long used in traditional medicine in East Asia, helped people with alcohol use disorder cut back on binge drinking, according to a UC San Francisco study published Nov. 4 in the American Journal of Psychiatry. The benefit was still there three months after they stopped taking it.
Binge drinking means having five or more drinks on one occasion for men, or four or more for women. It accounts for more than half of the roughly 80,000 U.S. deaths each year blamed on excessive drinking, UCSF says. Fewer than 10% of people with alcohol use disorder, the medical term for a drinking problem that harms someone’s health or life, have ever been given a medicine for it.
How the study worked
The researchers enrolled 120 adults with alcohol use disorder who binge drank at least once a week. Half were picked at random to get a standardized kudzu extract, meaning one made to contain consistent amounts of its active ingredients, and half got a placebo, a dummy pill. For 12 weeks, they were told to take it about 2.5 hours before they expected to drink heavily. Both groups also got brief weekly counseling.
By the end, the kudzu group’s binge-drinking days had fallen from an average of 2.15 a week to 1.42. The placebo group went from 2.15 to 2.06. The share of weeks with any binge drinking fell from 88% to 58% with kudzu, compared with 88% to 81% on placebo. Three months after treatment ended, the kudzu group still had significantly fewer binge-drinking days. People taking kudzu had no more side effects than those on placebo, and no serious side effects were linked to it, UCSF says.
The researchers think cutting back during treatment may have helped people rethink their drinking and build confidence that they could drink less. “What’s exciting 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,” said Glenn-Milo Santos, the study’s lead author and a professor in the UCSF School of Nursing.
Limits and what it means
The researchers caution that kudzu supplements sold in stores may not work the same way, because the study used a standardized formula and over-the-counter products can vary. The study was small and had counseling in both groups, and larger studies are needed to confirm the results in more kinds of people, they said. It was funded by the National Institutes of Health. Kudzu is not an approved treatment for alcohol use disorder.