Herbal Supplement Kudzu Cut Binge-Drinking Days by 27% in New Trial

Cutting back on heavy drinking is one of the hardest health goals to keep, and the medicines meant to help often sit untouched in the cabinet. A plant-based option may lower that bar. In a new clinical trial, adults with alcohol use disorder who took the supplement kudzu before expected drinking sessions had 27% fewer binge-drinking days than those on a placebo, with the biggest drop, 42%, among people who took it most regularly.

This approach centers on a plant used in Chinese medicine for more than a thousand years, taken only when someone expects to drink heavily rather than every day. Researchers gave kudzu to adults with alcohol use disorder who binge drink on a regular basis, instructing them to take a dose about two and a half hours before an anticipated heavy drinking session, much like someone might take an allergy pill before heading into a park full of pollen. Results of the trial, published in the American Journal of Psychiatry, pointed to benefits that held up even three months after treatment stopped.

Kudzu takes aim at no small problem. Binge drinking is linked to more than half of the roughly 80,000 alcohol-related deaths recorded each year in the United States, according to the study. Yet fewer than 10% of people with alcohol use disorder ever take medication for it, often because of worries about side effects or a general aversion to pharmaceuticals. A plant-based option people can control on their own terms could change the math for some.

How the Kudzu Trial Tested Binge Drinking

Researchers recruited 120 adults in the San Francisco Bay Area who had alcohol use disorder and binge drank at least once a week. Binge drinking was defined as five or more drinks in one sitting for men, or four or more for women. Half the group took a 2-gram dose of kudzu extract on days they expected to drink heavily; the other half took a matching placebo pill that looked and tasted the same. Neither the participants nor the research staff knew who was getting the real supplement, a setup known as a double-blind trial designed to prevent expectations from skewing the results. Both groups also attended weekly counseling sessions for 12 weeks aimed at helping them track their drinking and stay motivated to cut back.

Study participants were a mixed group. It included 62% white participants, 6% Hispanic/Latino participants, 12% Black participants, 7% Asian and Pacific Islander participants, and 14% who identified as multiracial or another race. Sixteen percent were living with HIV. More than half were men, 38% were women, and 4% identified as transgender or nonbinary. The median age was 39.

To confirm people were actually taking their medication, researchers used digital pill bottle caps that logged every time a bottle was opened. They also tested blood and urine for chemical traces of alcohol, giving an objective check against what participants reported about their own drinking.

What Researchers Found About Kudzu and Binge Drinking

People on kudzu had fewer binge-drinking days per week than those on placebo. By the end of the 12-week trial, the kudzu group’s average weekly binge-drinking days fell from about 2.15 to 1.42, while the placebo group barely budged, from 2.15 to 2.06.

Among participants who took their medication most consistently, roughly three times a week on average, the effect was even bigger. That same group also had fewer positive tests for PEth, a blood marker that reflects heavy drinking over several weeks.

Kudzu drinkers also had fewer weeks with any binge drinking, falling from 88% at the start to 58% by the end, compared with a much smaller dip, from 88% to 81%, in the placebo group. When researchers checked back three months after treatment ended, the kudzu group was still reporting fewer binge-drinking days than the placebo group, a sign the benefits didn’t evaporate the moment people stopped taking the pill.

Not every measurement told the same story. A urine test called EtG, which only picks up drinking from the past one to three days, showed no real difference between groups. The study authors noted this doesn’t undercut the main findings, since PEth, which captures a longer stretch of heavy drinking, did show benefits among people who took kudzu consistently.

Researchers also tracked whether people stuck with the treatment and tolerated it well. Eighty-eight percent of participants completed the full trial, and 84% completed weekly check-in visits, rates the researchers called high. Side effects were similar between the kudzu and placebo groups, and the most common complaints, including elevated blood sugar, dizziness, and nausea, occurred at comparable rates in both. One serious health event occurred in a kudzu-group participant: a case of myocarditis, a heart inflammation condition, that required hospitalization. It happened well after the person’s final treatment visit and was judged unrelated to kudzu.

Participants appeared to accept the approach. Seventy-eight percent reported being satisfied or highly satisfied with the study, and 91% said they’d be willing to join a similar study again.

Why This Could Matter for Binge Drinking Treatment

Kudzu has shown promise against heavy drinking before, but earlier studies were small, involving as few as 14 to 20 people, and tracked outcomes for only a week or a month. This trial followed 120 people for three months and checked back three months after that, offering a fuller picture of whether the effect holds up over time.

Kudzu’s appeal goes beyond whether it works. It comes down to how people take it. An herbal supplement that can be bought without a prescription and used only when needed removes some of the biggest obstacles that keep people with alcohol use disorder from starting treatment in the first place. For someone who doesn’t want to take a pill every day, or who worries about pharmaceutical side effects, an on-demand option rooted in a centuries-old remedy could make treatment more appealing. The researchers point to this as reason enough to pursue larger studies, not because kudzu is a cure-all, but because it fills a gap that current approved medications haven’t closed.

Disclaimer: These findings come from a single Phase 2b randomized trial of 120 adults and need confirmation in larger Phase 3 studies before kudzu can be recommended as a treatment. The trial tested one standardized extract; commercial kudzu supplements vary in formulation, and results may not apply to every over-the-counter product. Kudzu is not an approved treatment for alcohol use disorder and is not a substitute for medical care. Anyone considering a supplement for heavy drinking should speak with a healthcare provider first.

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