Effect of Kava on Anxiety and Stress in Cancer Survivors

Inclusion Criteria: * Completed curative-intent treatment for breast, gynecologic, lung, or head/neck cancer within the last 24 months without clinical and/or radiographic evidence of recurrence at the time of the last follow up * Score of ≥ 5 on the GAD-7 questionnaire, considered to be mild anxiety * ECOG performance status 0-1 * Normal kidney and liver function within 28 days prior to the first dose of kava or placebo * Willing to abstain from benzodiazepine and alcohol use during the kava or placebo intervention and for at least 14 days after completion * Ability to provide written, informed consent Exclusion Criteria: * Regular use of benzodiazepines, defined as ≥ 2 times weekly, within 14 days prior to study registration * Anti-cancer therapy within 28 days prior to registration, and/or during study participation, except for aromatase inhibitors * Known liver disease such as cirrhosis (any Child-Pugh class), active infectious hepatitis, immune-mediated hepatitis, hemochromatosis, non-alcoholic steatohepatitis (NASH), or Wilson's disease * Use of acetaminophen at doses more than 2000 mg daily for more than three days per week within 7 days prior to the first dose of kava or placebo intervention * Chronic use of high-intensity statin therapy * Significant uncontrolled conditions or situations, which in the judgment of the enrolling investigator, could affect safety and/or ability to adhere to study requirements * Adjustments in anti-depressants and/or anxiolytic medications within 8 weeks prior to study registration * Known allergy to kava * Women who are pregnant, intend to become pregnant, or are nursing * Regular use of alcohol, defined as ≥ 3 times per week, regardless of amount, within 14 days prior to study registration * Parkinson's disease * History of or current substance use disorder by self-report