The isoflavone puerarin reduces alcohol intake in heavy drinkers: a pilot study

Isoflavone compounds naturally occurring in the root of the kudzu plant have been used historically to treat alcohol-related problems. A pilot study was conducted to assess the effects of one primary isoflavone--puerarin--for its ability to modify alcohol intake in humans.

Ten (10) healthy adult volunteers were administered puerarin (1200 mg daily) in a double-blind, placebo-controlled, crossover design experiment for one week prior to an afternoon drinking session lasting 1.5h. Participants had access to up to six bottles of their preferred brand of beer in addition to juice and water. A time course of drinking, sip volumes, and total amount consumed were recorded.

Participants consumed on average 3.5 (±0.55) beers when treated with placebo and 2.4 (±0.41) beers when treated with puerarin. In contrast to drinking following placebo treatment when 3 participants drank 5 beers and 1 participant drank all 6 beers, none drank 5 or 6 beers when treated with puerarin. Drinking topography also changed. When treated with puerarin, participants decreased sip size, took more sips to finish a beer, and took longer to consume each beer. Additionally, after finishing a beer, latency to opening the next beer was increased.

This study is the first demonstration that a single isoflavone found in the kudzu root can alter alcohol drinking in humans. These results suggest that alcohol consumption patterns are influenced by puerarin administration and this botanical medication may be a useful adjunct in the treatment of excessive alcohol intake.