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Canada Bans the Dangerous Herbal Supplement Kava-Kava

Worst Pills, Best Pills Newsletter article October, 2002

Canada joined the growing list of countries that have banned the herbal supplement kava-kava because of liver toxicity that in some cases has resulted in liver transplants and death (see the May 2002 issue of Worst Pills, Best Pills News). An immediate ban and a recall at all levels of the market was announced by Canadian health authorities on August 21, 2002. A customs alert has also been issued to prevent further shipments of these products from entering Canada. The U.S. has not taken...

Canada joined the growing list of countries that have banned the herbal supplement kava-kava because of liver toxicity that in some cases has resulted in liver transplants and death (see the May 2002 issue of Worst Pills, Best Pills News). An immediate ban and a recall at all levels of the market was announced by Canadian health authorities on August 21, 2002. A customs alert has also been issued to prevent further shipments of these products from entering Canada. The U.S. has not taken comparable action.

The symptoms of serious liver toxicity include jaundice (yellowing of the skin or whites of the eyes) and brown urine. The non-specific symptoms of liver toxicity can include nausea, vomiting, light-colored stools, unusual tiredness, weakness, stomach or abdominal pain, and loss of appetite. Consumers using dietary supplements containing Kava-Kava who experience signs of liver toxicity should stop using the product and contact their physician immediately.

In addition to liver toxicity, kava-kava use has also been associated with adverse reactions that include an itchy scaly skin condition, known as kava dermopathy, muscle weakness and coordination problems.

Kava-kava is a plant used in a traditional ceremonial beverage in South Pacific islands. The islanders apparently do not supplement their diet with the drink but only use it on special occasions. Unregulated dietary supplements containing Kava-Kava are promoted in this country to be taken regularly for relaxation (to relieve stress, anxiety, and tension), sleeplessness, and menopausal symptoms.

The Canadian action follows an advisory issued on January 16, 2002, announcing the Canadian government’s intention to conduct a safety assessment as a result of worldwide reports of liver toxicity associated with kava-kava. In light of this assessment, the Canadian authorities now consider products containing kava-kava to be drugs and have determined that there are no acceptable food uses for the herb.

In contrast, under U.S. law—the Dietary Supplement Health and Education Act (DSHEA)—the Food and Drug Administration (FDA) does not have the authority to do what the Canadians have done. The “best” the FDA has done is to issue a health advisory about kava-kava on March 25, 2002.

There have been four cases of liver toxicity associated with the use of kava-kava containing products reported in Canada. None of the Canadian cases have resulted in death. Other foreign regulatory authorities (including Germany, Switzerland, the United Kingdom and the United States) have also received several reports of liver toxicity associated with the use of the herb, including three fatalities. Based on the currently available information, it is believed that individuals who may be at particular risk of liver toxicity associated with kava-kava use include those who have compromised liver function due to disease, age, or prior or current drug or alcohol abuse.

What You Can Do

Buyer Beware! You should not take dietary supplements. These products have not been tested or shown to be effective for any use, and their safety is unknown. The only exception to this advice is an inexpensive vitamin or mineral preparation.

Adverse events associated with the use of dietary supplements or other drugs should be reported as soon as possible to FDA’s MedWatch program by calling their toll-free number (1-800-332-1088) or through the Internet (www.fda.gov/medwatch.)