Several studies suggest pipermethystine induces
hepatotoxicity in humans, and was first believed to be the cause of liver failure in individuals consuming kava supplements, but not in proper root powder or fresh root, which is consumed in the traditional
kava cultures of Polynesia. Later analyses of the implicated drug materials and products revealed that medical kava extracts contain less than 45 ppm of this alkaloid, while the leaves contain about 0.2% (2000 ppm). Based on this retrospective study, pipermethystine is an unlikely cause for the observed hepatotoxicity of commercial kava preparations. == References ==