Following reports of liver toxicity, including liver failure, associated with extracts from the Pacific islands plant kava (Piper methysticum), these have been banned from sale as a herbal anxiolytic in many Western countries, to the detriment of Pacific island economies.
Pacific Islanders have used kava extensively for centuries, without recognised liver toxicity. However, the population is small, and there has been no systematic evaluation of possible liver damage.
For both economic and public health reasons, it is important to determine if kava is inherently hepatotoxic, and what the mechanisms of toxicity are.
Such research could lead to safer kava extracts for sale in Western countries, or identification of a subpopulation who should not consume kava.
- 1. Yadhu N, Singh Y. Kava: an overview. J Ethnopharmacol 1992; 37: 13-45.
- 2. Lebot.V, Merlin M, Lindstrom L. Kava. New Haven: Yale University Press, 1992.
- 3. Cawte J. Parameters of kava used as a challenge to alcohol. Aust N Z J Psychiatry 1986; 20: 70-76.
- 4. Campo J, McNabb J, Perel J. Kava-induced fulminant hepatic failure. J Am Acad Child Adolesc Psychiatry 2002; 41: 631-632.
- 5. Escher M, Desmeulus J, Giostra E, Mentha G. Hepatitis associated with kava, a herbal remedy for anxiety. BMJ 2001; 322: 139.
- 6. Strahl S, Ehret V, Dahm H, et al. Necrotising hepatitis after taking herbal remedies. Dtsch Med Wochenschr 1998; 123: 1410-1414.
- 7. Stevinson C, Huntley A, Ernst E. A systemic review of the safety of kava extract in the treatment of anxiety. Drug Safety 2002; 25: 251-261.
- 8. Kraft M, Spahn T, Menzel J, et al. Fulminant liver failure after administration of the herbal antidepressant kava-kava. Dtsch Med Wochenschr 2001; 126: 970-972.
- 9. Russmann S, Lauterburg BH, Helbling A. Kava hepatotoxicity [letter]. Ann Intern Med 2001; 135: 68-69.
- 10. McCutchan T. Fiji loses millions in kava export ban. The Daily Post [Fiji] 2003; 22 Jan: 1.
- 11. Murray W. Neoliberal globalisation, "exotic" agro-exports, and local change in the Pacific islands: a study of the Fijian kava sector. Singap J Trop Geogr 2000; 21: 355-373.
- 12. Mathews JD, Riley MD, Fejo L, et al. Effects of heavy usage of kava on physical health: summary of a pilot survey in an Aboriginal community. Med J Aust 1988; 148: 548-555.
- 13. Denham A, McIntyre M, Whitehouse J. Kava — the unfolding story: report on a work-in-progress. J Altern Complement Med 2002; 8: 237-263.
- 14. Whitfield JB. Gamma glutamyl transferase. Crit Rev Clin Lab Sci 2001; 38: 263-355.
- 15. Wanwimolruk S, Bhagwan S, Coffield PF, Chalcroft SC. Genetic polymorphism of debrisoquine (CYP2D6) and proguanil (CYP2C19) in South Pacific Polynesian populations. Eur J Clin Pharmacol 1998; 54: 431-435.
- 16. Buckley JP, Furgiulel AR, O'Hara MJ. Pharmacology of kava. In: Efron DH, Holmstedt B, Kilne NS, editors. Ethnopharmacological search for psychoactive drugs. New York: Raven Press, 1979; 141-145.
- 17. Klohs MW, Keller F, Williams RE, et al. A chemical and pharmacological investigation of Piper methysticum. J Med Pharm Chem 1959; 1: 95-99.
- 18. Singh YN, Blumenthal M. Kava — an overview. HerbalGram 1997; 39: 33-56.
- 19. Duve RN, Prasad J. Efficacy of extraction of constituents in the preparation of the Yaqona beverage. Fiji Agric J 1984; 45: 1-6.
- 20. Duve RN, Prasad J. Quality evaluation of Yaqona (Piper methysticum) in Fiji. Fiji Agric J 1981; 43: 1-8.
- 21. Pittler MH, Ernst E. Kava extract for treating anxiety (Cochrane Review). In: The Cochrane Library 2003; Issue 1. Oxford: Update Software.
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