Efficacy of kava extract for treating anxiety: Systematic review and meta-analysis

Synthetic anxiolytic drugs are effective for treating anxiety, but they are burdened with adverse effects, Constraints on resources and time often ren der therapies such as psychologic interventions impracticable. Thus, an eff ective oral medication with few adverse effects mould be a welcome addition to the therapeutic repertoire. This systematic review and meta-analysis wa s aimed at assessing the evidence for or against the efficacy of kava extra ct as a symptomatic treatment for anxiety. Systematic Literature searches w ere performed in the computerized databases MEDLINE, EMBASE, BIOSIS, AMED, CISCOM, and the Cochrane Library (all from their respective inception to Ju ne 1998), The search terms used were kava, kawa, kavain, Piper methysticum, and Rauschpfeffer (German term for Piper methysticum), Experts on the subj ect were contacted to provide further information. There were no restrictio ns regarding the language of publication. Double-blind, randomized, placebo -controlled trials of oral kava extract for the treatment of anxiety were i ncluded. All publications were blinded before assessment by a person not in volved in the study. Data were extracted in a standardized, predefined fash ion independently by the two reviewers. The methodologic quality of all tri als was assessed. Superiority of kava extract over placebo was suggested by all seven reviewed trials, The meta-analysis of three trials suggests a si gnificant difference in the reduction of the total score on the Hamilton Ra ting Scale for Anxiety in favor of kava extract (weighted mean difference, 9.69; 95% confidence interval, 3.54-15.83). These data imply that kava extr act is superior to placebo as a symptomatic treatment for anxiety. Therefor e, kava extract is an herbal treatment option for anxiety that is worthy of consideration.