Need for kava standardisation.
(Laws, regulations and rules)
Medicine, Herbal (Laws, regulations and rules)
Kava plant (Chemical properties)
Kava plant (Health aspects)
Cultivars (Chemical properties)
Cultivars (Health aspects)
Rhizoids (Chemical properties)
Rhizoids (Health aspects)
|Publication:||Name: Australian Journal of Medical Herbalism Publisher: National Herbalists Association of Australia Audience: Academic Format: Magazine/Journal Subject: Health Copyright: COPYRIGHT 2011 National Herbalists Association of Australia ISSN: 1033-8330|
|Issue:||Date: Spring, 2011 Source Volume: 23 Source Issue: 1|
|Topic:||Event Code: 930 Government regulation; 940 Government regulation (cont); 980 Legal issues & crime Advertising Code: 94 Legal/Government Regulation Computer Subject: Government regulation|
|Geographic:||Geographic Scope: Australia Geographic Code: 8AUST Australia|
Teschke R, Sarris J, Lebot V. 2011. Kava hepatotoxicity solution: a
six-point plan for new kava standardization. Phytomed 18:2-3;96-103.
This paper discusses the need for standardisation and quality control in the cultivation and distribution of kava products. Kava induced liver injury has been demonstrated in several patients worldwide and appears to be caused by unsuitable quality of the kava raw material. This has led to concerns that toxic liver disease may have been caused by association with the use of kava as herbal remedy and dietary supplement in Western countries. In response to this increasing interest in risk and usage, a thorough WHO report was issued.
Until the 2002 ban on kava based products, ethanolic and acetonic kava extracts had been sold as regulatory approved drugs in pharmacies without prescription in Germany and Switzerland. Medicinal kava varieties have a long and proven history of beneficial use amongst traditional Pacific herbalists for a variety of specific therapeutic effects. Side effects due to prolonged kava use at high dosage were well known among Pacific Islanders and Australian Aborigines. The risk of liver damage was directly related to the amount of kava consumed and in conjunction with the consumption of alcohol (a common risk factor). There was also a lack of regulatory standards at this time.
Prior to the ban efforts were not evident to clearly define the best kava cultivar(s) to be used. This remained unresolved by regulators, manufacturers and produces both in Western countries and the South Pacific Islands. As a result they did not consider that the various cultivars may differ in their specific positive and negative effects, including those with possible hepatotoxic ones. Certain cultivars known for their strong psychotropic (e.g. two days, Piper methysticum) and physiological (e.g. Piper wichmannii) effects are now banned as an export commodity. Prior to the kava ban ethanol, acetone and water have preferentially been used as media for kava extracts, but there was no regulatory statement regarding which medium may be superior. There was also no regulatory definition of the desired percentage of the kavalactones in the extracts.
Previously there was poor regulation of the parts used to extract kavalactones thereby compromising quality of product used in commercially available products. The kava plant has six parts used in planting, market and exports: stems, basal stems, chips of the rhizome, peelings of the rhizome, roots and residues. Observations have led to the conclusion that kava preparations made from the whole peeled root, as used traditionally, could be less likely to cause hepatotoxicity. This favourable statement should also apply to the rhizome, the preferred regulatory plant part.
The researchers have proposed a six point kava solution plan:
1) The use of a kava cultivar such as Borogu at least 5 years old at time of harvest. Borogu has a long tradition of cultivation in Vanuatu (the area of origin of Piper methysticum) and is well established for daily drinking without apparent side effects. It is known for its rapid effect thus a potential ideal candidate for future clinical studies.
2) The use of peeled and dried rhizomes and roots. The kava WHO report differentiates the rhizome from the roots and clearly defines the rhizome as the kava part below the stem and above the roots.
3) Products to be of aqueous extraction in preference to extracts prepared with chemical solvents. An initial study with aqueous kava extracts has shown preliminary results of safety and efficacy in treating patients with anxiety symptoms.
4) A dosage recommendation of [less than or equal to] 250 mg kavalactones per day. In Australia the maximum daily dose of kavalactones allowed for registered aqueous kava extracts to treat anxiety disorders is 250 mg.
5) Systematic rigorous future research. Further clinical trials with aqueous kava extracts are necessary to establish safety and efficacy of water based kava.
6) A Pan Pacific quality control system enforced by strict policing.
The intention of this six point kava solution plan is to advance the research, development and supply of kava globally, eventually leading to the return of kava to restricted markets.
Tessa Finney-Brown mnhaa
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