Update (July 2003): The Hawaii Agricultural Statistics Service (HASS) estimates farm revenues from the sale of kava ('awa) at $69,000 in 2002, down 88 percent from 2001. Production (fresh weight basis) totaled 60,000 pounds during 2002, down 87 percent from 2001.

Worldwide production of kava was severely curtailed in 2002 when certain European countries placed restrictions on the sale of food supplements and herbal medicines containing kava and/or kava extracts. This action was taken following the November 2001 release of a German study that claimed consuming kava-based or kava-containing products can lead to liver damage. Restrictions on kava products were also eventually adopted by countries such as Japan, Singapore, Canada, and the United Kingdom. Hawaii farmers felt the impact of this ban almost immediately as sales of kava dropped significantly during 2002. Although many farmers reported slow or no sales during the year, the majority of growers intended to keep their plantings. Disease also continued to be a problem for Hawaii growers.

Recently, a team of University of Hawaii scientists traced the kava-liver problem to extracts made from the peelings of the kava plant's stem bark which contain an alkaloid called pipermethystine. Preliminary test results showed that this alkaloid had a "strong negative effect" on liver cell cultures. Normally the stem bark is discarded but as demand for kava increased in the 1990's European extractors began purchasing the stem bark peelings and using the extract in kava products. Traditional kava drinkers only use the root of the plant which does not contain the alkaloid.

Original story (March 2002):

The Food and Drug Administration (FDA) is advising consumers of the potential risk of severe liver injury associated with the use of kava-containing dietary supplements. Kava (Piper methysticum) is a plant indigenous to the islands in the South Pacific where it is commonly used to prepare a traditional beverage. Supplements containing the herbal ingredient kava are promoted for relaxation (e.g., to relieve stress, anxiety, and tension), sleeplessness, menopausal symptoms and other uses. FDA has not made a determination about the ability of kava dietary supplements to provide such benefits.

Liver-related risks associated with the use of kava have prompted regulatory agencies in other countries, including those in Germany, Switzerland, France, Canada, and the United Kingdom, to take action ranging from warning consumers about the potential risks of kava use to removing kava-containing products from the marketplace. Although liver damage appears to be rare, FDA believes consumers should be informed of this potential risk.

Kava-containing products have been associated with liver-related injuries -- including hepatitis, cirrhosis, and liver failure -- in over 25 reports of adverse events in other countries. Four patients required liver transplants. In the U.S., FDA has received a report of a previously healthy young female who required liver transplantation, as well as several reports of liver-related injuries.

Given these reports, persons who have liver disease or liver problems, or persons who are taking drug products that can affect the liver, should consult a physician before using kava-containing supplements.

Consumers who use a kava-containing dietary supplement and who experience signs of illness associated with liver disease should also consult their physician. Symptoms of serious liver disease include jaundice (yellowing of the skin or whites of the eyes) and brown urine. Non-specific symptoms of liver disease can include nausea, vomiting, light-colored stools, unusual tiredness, weakness, stomach or abdominal pain, and loss of appetite.

FDA urges consumers and their health care professionals to report any cases of liver and other injuries that may be related to the use of kava-containing dietary supplements.

The presence of kava in a supplement should be identified on the product label in the "Supplement Facts" box. The following are commonly used names for kava:

FDA will continue to investigate the relationship, if any, between the use of dietary supplements containing kava and liver injury. The agency's investigation includes attempting to determine a biological explanation for the relationship and to identify the different sources of kava in the U.S. and Europe. The agency will alert consumers, and if warranted, take additional action as more information becomes available.