The researchbehind it.
EXTRO is built on studied botanicals, not folklore. These are independent, peer-reviewed sources on the ingredient classes we use, including the kava hepatotoxicity and safety literature, not claims about EXTRO itself. The same list is in our investor data room. See the cautions on the shop page, and ask your doctor before use if you take any medication.
Global Perspectives on KavaEconomidis, Lynch, Taylor et al. · Drug and Alcohol Review, 2025
Read Kava anxiolytic effect, meta-analysisCochrane review · effect size d = 2.24
Read A Chewable Cure "Kanna": biological and pharmaceutical properties of Sceletium tortuosumPMC8124331
Read Acute effects of Sceletium tortuosum (Zembrin) in the human amygdalaNature · Neuropsychopharmacology, 2013
Read Kava hepatotoxicity, a clinical reviewTeschke R. · Annals of Hepatology, 2010;9:251-65 · safety literature
Read Kava hepatotoxicity: a clinical survey and critical analysis of 26 suspected casesTeschke R. et al. · Eur J Gastroenterol Hepatol, 2008;20:1182-1193 · safety literature
Read A re-evaluation of kava (Piper methysticum)Ernst E. · British Journal of Clinical Pharmacology, 2007;64(4):415-417
Read Biological activity, hepatotoxicity, and structure-activity relationship of kavalactones and flavokavinsPMC8405297 · safety literature
Read Assessment of the risk of hepatotoxicity with kava productsWHO · Coulter D. et al.
Read Increase in poison center reports linked to kratom-containing kava productsCDC MMWR, 2025;75(wr/mm7512a1) · safety literature
Read EXTRO contains no kratom. We're naming the kratom-adulteration reports here because they're part of the honest safety picture around the kava-products category, and because it's exactly the kind of supply-chain risk our sourcing is built to avoid.