Authorities study killer-kava claims

New Zealand health authorities are investigating claims that kava-based products have caused widespread liver damage.

Reports from Europe say kava consumption has been linked to hepatitis and caused a need for liver transplants in some people.

A spokeswoman for the Ministry of Health said yesterday that inquiries were also being made of public health officials.

On New Year's Eve, the United States Food and Drug Administration (FDA) announced an inquiry into the possibility that kava sold as a herbal remedy to promote sleep and stress relief could damage the liver.

These products can be found on the shelves under the name "kava-kava" or even "kawa" (not to be confused with the New Zealand native shrub kawa which is used as a medicinal herb).

Britain's Medicines Control Agency has already negotiated with herbal food industry organisations a "voluntary" withdrawal of kava from store shelves.

In France, products containing kava have been suspended from sale and a recommendation made that patients stop taking these.

These actions follow the linking of kava extract to dozens of cases of hepatitis in Europe.

The precautions were taken after health authorities in Germany and Switzerland informed the French Health Products Safety Agency that they had recorded "about 30 cases of hepatitis" among people who had taken kava-based products, the French agency said.

"One person died and four other patients had to have a liver transplant. These cases can occur unexpectedly and after several months of taking kava. In some cases, the kava-based products were taken off and on."

Kava is extracted from the root of a species of pepper plant called Macropiper methysticum, which thrives in tropical and subtropical climates in the South Pacific.

It is sold in health-food shops, on the internet and even in supermarkets as a "natural" beverage that is supposed to relieve stress and anxiety while promoting relaxation, mental clarity and mild euphoria.

It is supposedly free of the side-effects of prescription drugs.

Most users add the powdered extract to tea, coffee, cocoa or milk, although fizzy kava sodas and alcoholic kava drinks are also produced.

Some drink it with a glass of wine or beer to enhance the effect, and others take it as a sedative at bedtime.

In New Caledonia, Dr Yann Barguil, a biopharmacist and researcher at Noumea Gaston Bourret hospital, told the daily newspaper Les Nouvelles Caledoniennes that he was unsurprised by the emergence of a kava-related pathology but said that only about one person in 170,000 was potentially affected.

"In New Caledonia, we have detected three cases of hepatitis linked to the consumption of kava," he said.

"We believe the active properties of this plant, the kavalactones, have an effect on the liver's enzymes.

"And one person in about 170,000 has in his or her liver a type of enzyme that, if combined with kava, could produce a toxic enzyme," Dr Barguil said.

"This could provoke a sort of allergy that would eventually destroy the liver."

- NZPA

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