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Human Liver Microphysiological System for Assessing Drug-Induced Liver Toxicity In Vitro
Published on: January 31, 2022
Kava hepatotoxicity--a clinical review
1Department of Internal Medicine II, Division of Gastroenterology and Hepatology, Klinikum Hanau, Teaching Hospital of the Johann Wolfgang Goethe-University Frankfurt/Main, Germany. rolf.teschke@gmx.de
Annals of Hepatology
|August 20, 2010
Summary
Kava may cause liver damage in some individuals, especially with overdose, long-term use, or other medications. Standardization of kava products is needed to reduce these hepatotoxic risks.
Area of Science:
- Pharmacology
- Toxicology
- Ethnobotany
Background:
- Kava (Piper methysticum) is a traditional South Pacific plant used as an anxiolytic herb.
- Concerns about kava-induced liver disease led to regulatory actions, including a German ban on certain extracts in 2002.
- The causality between kava use and liver injury has been a subject of international debate.
Purpose of the Study:
- To critically analyze clinical data on suspected kava hepatotoxicity.
- To identify risk factors associated with kava-induced liver injury.
- To propose recommendations for minimizing the risk of kava hepatotoxicity.
Main Methods:
- Review of clinical data from 14 patients with liver disease linked to kava use.
- Application of a structured, quantitative causality assessment method specific to hepatotoxicity.
- Analysis of different kava extract solvents (aqueous, ethanolic, acetonic) and comedications.
Main Results:
- Causality for kava was assessed as highly probable (n=1), probable (n=4), or possible (n=9) across various extract types and mixtures.
- Identified risk factors included overdose, prolonged treatment, and comedication with other drugs and supplements.
- Hepatotoxicity occurred irrespective of the solvent used, suggesting poor raw material quality as a contributing factor.
Conclusions:
- Kava can be hepatotoxic in susceptible individuals, influenced by dosage, duration, and comedications.
- Poor quality of kava raw material is a likely trigger for hepatotoxicity.
- Standardization of kava products is essential to mitigate hepatotoxic risks.
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