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Planta Med 2015; 81(18): 1647-1653
DOI: 10.1055/s-0035-1558295
Perspectives
Georg Thieme Verlag KG Stuttgart · New York

German Kava Ban Lifted by Court: The Alleged Hepatotoxicity of Kava (Piper methysticum) as a Case of Ill-Defined Herbal Drug Identity, Lacking Quality Control, and Misguided Regulatory Politics

Kenny Kuchta
1   National Institute of Health Sciences, Division of Pharmacognosy, Phytochemistry and Narcotics, Setagaya-ku, Kamiyoga, Tokyo, Japan
,
Mathias Schmidt
2   HerbResearch Germany, Tussenhausen-Mattsies, Germany
,
Adolf Nahrstedt
3   Institut für Pharmazeutische Biologie und Phytochemie, Westf. Wilhelms-Universität, Münster, Germany
› Author Affiliations
Further Information

Publication History

received 08 September 2015
revised 19 October 2015

accepted 23 October 2015

Publication Date:
22 December 2015 (online)

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Abstract

Kava, the rhizome and roots of Piper methysticum, are one of the most important social pillars of Melanesian societies. They have been used for more than 1000 years in social gatherings for the preparation of beverages with relaxing effects. During the colonial period, extract preparations found their way into Western medicinal systems, with experience especially concerning the treatment of situational anxiety dating back more than 100 years. It therefore came as a surprise when the safety of kava was suddenly questioned based on the observation of a series of case reports of liver toxicity in 1999 and 2000. These case reports ultimately led to a ban of kava products in Europe – a ban that has been contested because of the poor evidence of risks related to kava. Only recently, two German administrative courts decided that the decision of the regulatory authority to ban kava as a measure to ensure consumer safety was inappropriate and even associated with an increased risk due to the higher risk inherent to the therapeutic alternatives. This ruling can be considered as final for at least the German market, as no further appeal has been pursued by the regulatory authorities. However, in order to prevent further misunderstandings, especially in other markets, the current situation calls for a comprehensive presentation of the cardinal facts and misconceptions concerning kava and related drug quality issues.

Key words

Piper methysticum - Piperaceae - Kava - efficacy - hepatotoxicity - risk-benefit-relation - drug quality
 

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