Primary Outcomes

Description: Reduction of participant's anxiety will be assessed on the HAMA from baseline to week 16 across time used a mixed methods model.

Secondary Outcomes

Description: Will assess whether response to Kava will be moderated by gamma-aminobutyric acid (GABA) transporter polymorphisms. Specifically, whether rs2601126-T allele or rs2697153-A allele carriers have greater reduction of anxiety

Other Outcomes

Description: Depressive symptoms on the Montgomery-Asberg Depression Rating Scale (MADRS), self-rated anxiety on the Beck Anxiety Inventory (BAI), pathological worry on the Penn State Worry Questionnaire (PSWQ), and health-related quality of life on the Short Form Survey-12 (SF-12) will also be significantly improved by Kava over placebo; and

Description: Differential gene expression will be assessed from baseline to week 8 from participants in the Melbourne site. This will determine whether Kava increases expression of genes effecting expression of neurochemical e.g. GABA, and monoamines