Often consumed as tea, a medicinal plant from the South Pacific also relieves anxiety, safely and effectively.
The first clinical trial of the plant found that a water-soluble extract of kava, administered as tablet, was effective in treating anxiety and improving mood.
Jerome Sarris, doctoral candidate from University of Queensland School of Medicine, said the placebo-controlled study found Kava to be an effective and safe treatment option for people with chronic anxiety and varying levels of depression.
"We've been able to show that Kava offers a natural alternative for the treatment of anxiety, and unlike some pharmaceutical options, has less risk of dependency and less potential of side effects," said Sarris, who conducted the study.
Each week participants were given a clinical assessment as well as a self-rating questionnaire to measure their anxiety and depression levels.
Researchers found anxiety levels decreased dramatically for participants taking five tablets of kava per day as opposed to the placebo group which took dummy pills.
"We also found that kava had a positive impact on reducing depression levels, something which had not been tested before," Sarris said.
In 2002, kava was banned in Europe and Canada due to concerns over liver toxicity.
While the three-week trial raised no major health concerns regarding the kava extract used, the researchers said larger studies were required to confirm the drug's safety.
"When extracted in the appropriate way, kava may pose less or no potential liver problems. I hope the results will encourage governments to reconsider the ban," Sarris said.
"Ethanol and acetone extracts, which sometimes use the incorrect parts of the kava, were being sold in Europe. That is not the traditional way of prescribing kava in the Pacific Islands," he added, according to a university release.
The results are scheduled for publication in Psychopharmacology.