Kudzu, the fast-spreading weed also known as the "vine that ate the South," contains chemicals that reduce the urge of binge drinkers and alcoholics, as well as casual imbibers, to ask for that second, third or fourth drink, Harvard Medical Center researchers report in what is being called a groundbreaking study.

Their research suggests that kudzu compounds called isoflavones are keys to treating intoxication. Heavy drinkers who took pills made from chemicals in kudzu seemed to lose their urge to order a second or third drink or, at the very least, extended the time between ordering additional drinks.

"We want to develop a medication that would be effective and safe, and pills without side effects like other drugs on the market" for treating alcoholics and binge drinkers, said lead researcher Dr. Scott E. Lukas, a professor of psychiatry at Harvard Medical School and director of behavior psychopharmacology at McLean Hospital in Belmont, Mass.

Harvard and McLean own the patents on the discovery, and Lukas speculated it might be several years before alcohol-resistance pills are developed. That depends on whether the pills will need approval by the Food and Drug Administration (FDA) or can be sold as an herbal remedy, which would not require the government's approval.

The FDA has approved three drugs to treat alcoholism:

* naltrexone, which reduces the desire to drink.

* acamprosate, which appears to modify urges or thoughts about drinking.

* disulfiram, which makes people extremely sick if they consume alcohol.

All are man-made and have side effects ranging from nausea to diarrhea.

The ingredients extracted by Lukas -- from kudzu roots, leaves and stems -- appear to prolong or enhance the "acute effects of the first drink," he said in an interview. "Apparently, this effect is sufficient to delay or eliminate the desire to drink subsequent beers."

The study was done with 11 men and women -- all of whom consumed an average of 25 alcoholic drinks a week -- who spent six hours over a six-week period in a studio apartment, complete with satellite TV and a refrigerator filled with their favorite brews.

They were told to drink as much as they pleased for 90 minutes and then go home. Sometimes they were given kudzu pills and other times placebos.

"Eight drank fewer beers while receiving kudzu versus placebo treatment; two drank the same number of beers, and one drank one more beer," Lukas said.

Dr. David Overstreet, a researcher in the Center for Alcohol Studies at the University of North Carolina at Chapel Hill, called the study "groundbreaking" but said it needs to be replicated.

Scientists have shown that kudzu extracts reduce alcohol craving in rats but never before in humans, said Dr. Raye Litten of the National Institute on Alcohol Abuse and Alcoholism.

People in China have been using kudzu to treat a variety of problems, from rashes and obesity to alcoholism and hangovers, for at least 1,600 years. Liver tonics and pills made from kudzu and kudzu roots are available in health food stores everywhere.

The runaway vine, brought to this country from China in 1876, was originally popular as a shade plant but was demoted to weed status in 1972 by the U.S. Department of Agriculture.

Lukas said he is not recommending that people chew on kudzu leaves or roots before going to parties. A lot of the kudzu-based herbal remedies contain minced pieces of the plant, but very little of the ingredients that seem to fight drinking urges.

He said the patent owners "are looking for people who might want to license it and develop it. This is not going to eliminate drinking, but I would argue that if I could get someone who drinks 26 down to eight, I could detox them. And that's the strategy."