Kava Article
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Thank you for a very complete exposition of the kava situation which I
will pass on to others interested in Herb Safety.
Elwood Richard, President
Now Foods
-----Original Message-----
From: Mathias Schmidt [SMTP:[email protected]]
Sent: Monday, June 21, 2004 11:50 AM
Dear Dr. Blumenthal,
I understand the position you are taking regarding the differentiation
between acetonic and ethanolic extracts - after the paper of Stickel et
al. in the journal of hepatology anybody not familiar with the case details
must necessarily come to your point of view.
But not when you know the real data (see for example the Gruenwald report,
where the knowledge as of Summer 2003 is assembled), and the things that
happened in the background, the conclusion is different.
Let me fist state one important issue: The whole discussion of liver
toxicity was not started in Germany in forst place, but in Switzerland.
There, the IKS (now SWISSMEDIC) examined 9 cases of liver injury
supposedly caused by kava in 1999. The IKS made a differentiation between acetonic
and ethanolic extracts, for a simple reason: 8 out of the 9 caser reports
concerned the acetonic extract, and only one report an ethanolic exctract.
This latter report was already published in 1998 by Strahl et al., and
later on turned out to have been caused by a sensitization against kava in a
patient deficient in cytochrome P450 2D6. This led to the discussion of a
potential correlation between liver toxicity and metabolic peculiarities,
but it did not lead anywhere. In fact, there is a much simples explanation
(see below).
One year after the drug safety protocol in Switzerland was concluded with
the ban of the ethanol extract and almost no consequences for the
ethanolic extract besides being shifted from free sale to pharmacy only, the Germans
started their own drug safety protocol. In contrast to the regulations,
the BfArM turned directly to the public with a verdict, which caused a bias in
all further discussions. Kava had already been selected as the culprit, so
it was pretty clear that all future publications did not need to take a
closer look at their case reports. An example is the Australian case
report, where two out of three components in the preparation were adulterated, and
still the authors blamed kava - and argued that they could not know what
the tablets really contained!
Another example is a case report where the patient had taken a 10fold
overdose of chromium for a prolonged time, and in addition concomitant
medication. Again, of course it was kava.
Yes, you are right. There are a number of BfArM case reports where
ethanolic
kava products were taken (amongst others). But: the fact that a drug was
taken is per se no proof of a causality. And all of the cases you are
referring to are rather sketchy, most of them having comedication which is
known to cause adverse liver effects. In other cases alcohol played a
role,in yet other cases there were other factors which did not allow to
establish a clear causal correlation between kava and the adverse effect. With the
exception of the already mentioned case report of Strahl et al., there is
not a single case report good enough to allow the conclusion of potential
liver toxicity from ethanolic extracts!
A number of papers appeared where the case reports were discussed. Most of
them were based on the original BfArM linelisting, which contained a lot
of errors: duplicate or triplicate entries, missing indications of
comedications, wrong statements regarding challenge/rechallenge etc.
Without a closer look at the case data (which was not laid open by the BfArM, but
I had access to the details though the companies involved!) you may easily
come to a wrong conclusion. The best, or maybe the worst example is the
paper of Stickel et al. in the Journal of Hepatology. The authors claim
they obtained the case data from the BfArM. Did they? In almost all case
reports Stickel et al. report wrong data: age of patients, gender, concomitant
treatments, and, worst of all, liver data that was never taken! I could
demonstrate this to you in detail for a number of case reports. So, if
this is the evidence pointing to ethanolic extracts, it is exactly the kind of
view certain circles in Germany want to create.
A farfetched sort of conspiracy theory? I do not think so. We are now
getting closer to a simple answer to the complex problem.
As I said, the case reports in Switzerland all came up in 1999, and all
(but one) for the acetonic extract. We now know that at the same time, there
were two different kinds of acetonic extract on the market, not just one. One
was made from a Samoan kava cultivar which is locally favored for daily use,
and has never given rise to any problem even though it is locally consumed in
much higher doses than in Europen kava products. We have reason to believe
that this kava cultivar was sold on the German market.
However, towards 1999, the company switched over to a cultivation of
another kava cultivar. For this, they selected a Vanuatu cultivar from the
socalled "Tudei"-family. Tudei-kava is locally not used because it has very
unpleasant effects. So please note that a kava cultivar was used which
must not be exported except on a very specific demand. We have witness
statements from the South Pacific warning the company against the use of this
cultivar.
Even worse: We were told that the not only the wrong cultivar was chosen,
but also the wrong kind of raw material: a high percentage of stem
peelings instead of the roots. There is a higher yield of kavalactones in the stem
peelings, but also a number of phytochemical compounds not present in the
roots! Kava preparations made with this kind of raw material are not
comparable to kava as it is usually defined. We have reason to believe
that this second acetonic extract was sold in Switzerland in the time when the
whole mess happened!
Our evidence is based on analytical data, which is still being completed,
and of toxicological studies, all pointing the same direction. There is
now a number of recent studies showing that the use of the aerial parts is
potentially dangerous.
We are close to the point when questions will have to be asked in Germany
how much the authorities knew of the change in quality of the acetonic
kava extract, and why a differentiation of the extracts was always turned down.
Kind regards
Mathias Schmidt
Dr. Mathias Schmidt
Herbresearch Germany
Im Westfeld 29
D-33428 Harsewinkel
Tel.: +49-2588-9199134
Fax: +49-2588-918058
Etc
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