Researchers at the University of Queensland in Australia have found a traditional extract of Kava, a medicinal plant from the South Pacific, to be safe and effective in reducing anxiety.
To be published online this week in the Springer journal Psychopharmacology, the results of a world-first clinical trial which found that a water-soluble extract of Kava was effective in treating anxiety and improving mood. The Kava was prescribed in the form of tablets.
Lead researcher Jerome Sarris, a PhD candidate from UQ's 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," Mr. Sarris said.
Each week participants were given a clinical assessment as well as a self-rating questionnaire to measure their anxiety and depression levels. The 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," Mr. Sarris said.
In 2002 Kava was banned in Europe, UK 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," Mr. 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. Our study used a water-soluble extract from the peeled rootstock of a medicinal cultivar of the plant, which is approved by the Therapeutic Goods Administration of Australia and is currently legal in Australia for medicinal use."
Sarris J et al. (2009). The Kava Anxiety Depression Spectrum Study (KADSS): a randomized, placebo-controlled crossover trial using an aqueous extract of Piper methysticum. Psychopharmacology. DOI 10.1007/s00213-009-1549-9