From The July 2000 Issue of Nutrition Science News

Kava Quells Anxiety

Kava (Piper methysticum) is a winner for treating anxiety. That's the conclusion reached by Max Pittler, M.D., of the University of Exeter in the United Kingdom. Pittler carried out a comprehensive literature review of 14 double-blind, placebo-controlled clinical trials performed on kava, selecting seven as being properly conducted. All seven found kava to be more effective for treating anxiety than placebo. The trials included people with an age range of 36 to 60 who, for between one and 24 weeks, daily consumed kava extracts containing 60 to 240 mg of the active ingredient, kavapyrones.

Three of the studies used the Hamilton Rating Scale for Anxiety as an endpoint and included only patients initially scoring 19 or higher on the scale so their data could be pooled in a meta-analysis. This meta-analysis found that kava significantly reduced—by 10 points—the Hamilton scale.

Kava seems to be as effective as the class of synthetic pharmaceuticals called benzodiazepenes (such as Valium) for treating anxiety, but without their dangerous side effects of sedation and addiction. Only about 2 percent of patients taking kava reported minor side effects, predominantly gastrointestinal complaints, skin reaction, headache and photosensitivity. Other research has shown that kavapyrones act on receptors in the hippocampus and amygdala complexes in the brain to produce measurable changes in brain wave activity. Statistics show that almost 25 percent of Americans will suffer from an anxiety disorder in their lifetimes.

—Journal of Clinical Psychopharmacology 2000 Feb;20(1):84-9