Study Finds St. John's Wort Can Cut Alcohol Consumption

"This is exciting - and simple -- because St. John's wort already is the most often prescribed antidepressant in Germany," said Dr. Amir H. Rezvani, research associate professor of psychiatry at the UNC-CH School of Medicine. "It is reported to be as effective as Prozac and produce fewer side effects."

Rezvani presented his findings Tuesday (June 23) in Hilton Head, S.C., at the annual meeting of the Research Society on Alcoholism. He also will present them in Copenhagen next week at a meeting of the International Society of Biomedical Research on Alcoholism.

St. John's wort, or Hypericum perforatrum, grows wild in Europe, western Asia, North Africa and in North America, particularly the Pacific Northwest, he said. It is a common wildflower with vivid yellow flowers edged with tiny black beads. When rubbed, the plant releases a red pigment containing hypericin.

The UNC-CH experiments involved rats that were selectively bred to prefer alcohol. When given a choice, such rats will consume little water, but much alcohol, said Rezvani, also adjunct associate professor of social medicine.

"In one set of experiments, we gave the compound to the rats by mouth and then gave them free access to water and alcohol for 24 hours," the scientist said. "We then measured their alcohol intake every two hours, and found that those receiving the compound drank less, about 50 percent less than the untreated animals."

Rezvani and his colleagues at the SkipperBowles Center for Alcohol Studies got the same results with two different strains of rodents -- P rats and fawn-hooded rats -- and also when they continued the experiments up to 15 days.

"We don't know yet whether the compound will work in human alcoholics, but we are optimistic," he said. "Since it is an herb, it should have no side effects or fewer side effects than synthetic drugs. One of the major problems with alcoholics is that they don't like to take medications that have side effects. St. John's wort might be different in that it would just reduce their desire for alcohol."

The scientist said he became curious about the herb after reading and hearing reports last year on its anti-depressive properties.

"I thought that since depression and alcoholism have a strong biological link, if it worked for depression, then it might just have a beneficial effect on alcoholism as well," he said. "Many people think the link may be a deficiency in serotonin, a neurotransmitter in the brain."

Since alcoholism is a complex disease, it is unlikely that any single "magic bullet" will be found that will prevent or cure it, Rezvani said. Still, combining several effective compounds that alter brain chemistry safely probably could lessen its severity in people motivated to change.

The U.S. Food and Drug Administration has not approved St. John's wort for medical purposes.