Re-introduction of Kava (Piper methysticum) to the EU: Is There a Way Forward?

Jerome Sarris; Rolf Teschke; Con Stough; Andrew Scholey; Isaac Schweitzer

doi:10.1055/s-0030-1250290

Planta Medica, Table of Contents

Planta Med 2011; 77(2): 107-110
DOI: 10.1055/s-0030-1250290

Perspectives

Re-introduction of Kava (Piper methysticum) to the EU: Is There a Way Forward?

Jerome Sarris¹ ^, ² , Rolf Teschke³ , Con Stough² , Andrew Scholey² , Isaac Schweitzer¹

¹Department of Psychiatry, Faculty of Medicine, The University of Melbourne, Melbourne, Australia
²Brain Sciences Institute, Swinburne University of Technology, Melbourne, Australia
³Department of Internal Medicine II, Section of Gastroenterology and Hepatology, Klinikum Hanau, Teaching Hospital of the Johann Wolfgang Goethe University of Frankfurt/Main, Germany

Abstract

Kava (Piper methysticum) is an effective anxiolytic that has been withdrawn from various consumer markets in European countries due to concerns over its hepatotoxicity. It is plausible that the reported hepatotoxicity may be due in part to plant substitution, or an incorrect cultivar, or plant parts being used (such as leaves or bark); thus both the plant chemotype and the plant part used may be critical factors. If re-institution of kava in the EU is to occur, more evidence is required to determine its safety and efficacy. Furthermore, according to current evidence, the study of traditional water soluble rhizome extracts using a noble cultivar of kava may be advised. The Kava Anxiety-Lowering Medication (KALM) project is due to start in late 2010 to address these considerations. The KALM project uses an aqueous rhizome extract of a noble cultivar of kava in participants with generalised anxiety and Generalised Anxiety Disorder (GAD). The project comprises of 1) an acute RCT, kava (180 mg of kavalactones) versus oxazepam and placebo in 20 anxious people, testing effects on cognition, mood, anxiety, and driving; 2) an 8-week RCT comparing kava (120 mg kavalactones) versus placebo in 100 patients with GAD. To assess differences between dosages, non-responders at 3 weeks will be titrated to 240 mg of kavalactones. The project will also assess the effects of kava on liver function tests and its side effects profile. A novel component of the project is the pharmacogenomic exploration of phenotypical responses (GABA system and cytochrome P450 markers). The results of the study may be of benefit to sufferers of anxiety and the future economy of the Pacific islands, potentially providing an important step in the way forward with kava.

Key words

kava - Piper methysticum - Piperaceae - kava hepatotoxicity - anxiety - generalised anxiety disorder - pharmacogenomics

Full Text

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Dr. Jerome Sarris

Department of Psychiatry
The University of Melbourne
The Melbourne Clinic

130 Church Street, Richmond

Victoria 3121 Melbourne

Australia

Phone: + 61 3 94 20 93 50

Fax: + 61 3 94 27 75 58

Email: j.sarris@uq.edu.au