Once Deemed Safe, Kava Now Linked With Liver Damage
Sometimes, disappointing news appears about a natural product that seems to benefit our health. Such is the case with kava, a herbal remedy sold in the United States as an alternative pain reliever, relaxation aid and memory enhancer.
Recent reports from Germany and Switzerland suggest that kava may damage the liver. At least 24 cases of liver toxicity associated with the use of kava products have been reported internationally, including one death and several patients who required liver transplantation. The Swiss government has prohibited the sale of all products containing kava extract.
And Canadian health officials have warned consumers not to use any products that contain kava. Government warnings indicate that kava may be an ingredient in herbal and homeopathic preparations sold to treat anxiety, nervousness, insomnia, pain and muscle tension, and those warnings are reminders about the importance of reading labels on all herbal products. Canadian officials also advise consumers to contact their physicians if they experience any adverse effects from taking products containing kava.
The following symptoms may be associated with liver problems: jaundice (yellowing of the skin or whites of the eyes); brown urine; nausea or vomiting; unusual fatigue or weakness; and stomach or abdominal pain.
The U.S. Food and Drug Administration has not yet issued a warning about kava. Last December, however, the agency asked physicians to report cases of patients experiencing liver toxicity to determine whether such cases may be related to kava in dietary supplements.
Despite international concern, kava is still widely available in this country. I checked with a leading health food and vitamin retailer in New York and another in Los Angeles that were still displaying kava products for sale on their shelves and in catalogs.
The kava situation and the absence of federal regulations to protect consumers demonstrate the need for caution when purchasing over-the-counter food supplements. Although manufacturers are urged to register claims that are printed on product labels with the FDA, the Dietary Supplement Health and Education Act of 1994 leaves the FDA with little or no authority to regulate vitamins, herbs and other nonprescription remedies for safety until a disaster or near disaster has occurred.
Under the 1994 rules, the manufacturer--not the federal government--is responsible for ensuring that a dietary supplement is safe before it is marketed. The FDA can restrain sales or recall a product only after dangerous or life-threatening results are reported.
There are more than 90,000 Web sites referencing kava. I would recommend such sites as the FDA’s www.fda.gov and the American Botanical Council’s Web site, www.herbalgram.org. It is best not to depend on promotional information offered on most Web sites. One site I looked at described the reports of liver damage from kava use in Europe, but a few paragraphs later stated, “Thus far, research shows kava to be safe.”
Kava remains an important part of social, cultural and religious life of South Pacific islanders. Often served from a large wooden bowl at social and ceremonial events, it is passed around and consumed by people seeking to relax, loosen up and feel good. It is not, apparently, consumed on a regular basis, and this may be a key distinction. Regular use of kava over a long period may create problems though occasional use may be safe or at least less problematic.
Although it has not been studied thoroughly, good scientific studies suggest that kava extract is superior to placebo against anxiety and, until recently, kava was described as safe. There is much to be learned about the potential benefits and safe use of kava. For the time being, however, the possibility of serious liver damage is reason enough to think twice about using it and to be sure to talk to your doctor before trying it. Personally, I don’t think it’s worth the risk.
Other herbal therapies used to treat stress or insomnia include valerian capsules and chamomile or passion flower tea. Melatonin, a substance produced naturally by the body in response to light, also is available as a supplement and used against sleeplessness and jet lag. These products can interact with other sedatives and should not be taken for more than a few days, as continued use may mask underlying problems that require medical attention.
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Cassileth can be reached at drcassileth@aol.com. Her column appears the first Monday of the month.
