Kava – Benefits and Safety


Cheryl Hoard


Many physicians in Germany prescribe Kava Kava Root (Piper methysticum)as a first line of defense for symptoms associated with anxiety. Alternatively, the common chemical prescription is Valium which belongs to a class of conventional drugs called benzodiazepines. Kava Kava does not cause the side effects associated with these drugs and in clinical trials has been shown to be therapeutically similar. It is the kavalactone constituents that offer many of the actions attributed to Kava. They leave your mind sharp while your body relaxes – without the possibility of addiction. Their analgesic effect matches a typical 200 milligram aspirin.

Besides the popular use of Kava for muscle relaxing, soothing anxiety and tension, other uses can relieve headaches, hyperactivity in children, insomnia and aid in the treatment of depression. A lesser known benefit of this root is its anti-inflammatory and analgesic effect on the urinary system, particularly for women. It has been used for conditions like bladder & urinary tract inflammations and the kavalactones are also recognized for their ability to relax the uterus, making it useful for menstrual cramps.

In Polynesia, Kava tea is highly popular and even considered more socially acceptable than alcohol. It has been served to famous visitors that include Lyndon and Lady Bird Johnson, Pope John Paul II, Hillary Clinton and Queen Elizabeth II.

The current safety cautions for Kava are as follows: Avoid during pregnancy, nursing and some kinds of depression. Not recommended for more than 3 months without medical advice. It could increase the effect of alcohol, barbiturates and some drugs used for psychological treatment and has the potential to affect motor reflexes and judgment when driving or operating heavy machinery.

In recent months concerns have been raised about the possibility of liver damage with the consumption of Kava. According to Mark Blumenthal, executive director of the American Botanical Council, “…Kava is being anecdotally linked to reports of liver dysfunction without any confirming scientific evidence.” Reports from a few countries in Europe prompted the international scrutiny Kava is undergoing now. The FDA is still evaluating the cases in question. Unfortunately, while still evaluating and before even coming to any conclusions, they issued a warning that Kava Kava MAY be linked to liver problems.

When the reports from Europe surfaced, a check of the FDA database found no reports of adverse liver effects associated with Kava in the USA. The database did contain 29 of a total of 35 USA Kava “adverse event reports” which turned out to be from a young man distributing what was called a Kava product at a rave that actually was 1,4-butanediole, containing no herbs or natural dietary supplement ingredients. Unfortunately publications like The New York Times use this FDA database as a source of information and in an article on January 16, 2002 reported these cases as problems related to the use of Kava Kava. Some of the Kava products used in the other cases in this database contained multiple ingredients other than Kava.

France has already banned the sale of Kava products based on 30 case reports from Germany and Switzerland that only identify it as a POSSIBLE cause in liver problems. The Kava product used in many of these reports was an acetone-based extract that was highly concentrated to 70% kavalactone content. Factors including simultaneous use of liver damaging medications, viral infections and alcohol abuse were not ruled out in many cases. Eighteen cases actually were related to these factors raising doubts about the validity of some of the reports.

In a report commissioned by the American Herbal Products Association, Council for Responsible Nutrition, National Nutritional Foods Association and Utah Natural Products Alliance, Donald Waller, Ph.D., from the University of Illinois-Chicago and board-certified toxicologist, said there is no scientifically supported association of liver disease with the use of Kava which can be found using the FDA case reports. The FDA is reviewing 38 Americans with medical problems possibly associated with Kava use. Two of these cases involving chronic or high-dose Kava consumption did not even result in liver damage which may indicate Kava does not adversely effect the liver. Because of the conflicting information and the seriousness of the claims The American Botanical Council has recommended if one is already taking prescription medication associated with liver damage, consumes alcohol regularly or has a preexisting liver disease, not to use Kava Kava. They also recommend, since the reports so far are connected to chronic or excessive use, that Kava should not be taken on a daily basis for more than 4 weeks without the advice of a qualified professional. In addition they also state to discontinue use if symptoms of jaundice (e.g., dark urine, yellowing of the eyes) occur.

There is very little evidence in the previously existing scientific literature to associate Kava with liver toxicity. The herb has been safely used in Polynesia for centuries. When the above mentioned groups, AHPA, CRN, NNFA and UNPA issued a press release in December 2001, AHPA president Michael McGuffin was quoted as saying “Despite the fact that the Kava products under scrutiny are ones manufactured and sold in Europe, we believe that it is critical that Kava’s long history of safe use be reaffirmed by a review of the information.”


June, 2002


Anon. FDA Issues Warning on Kava Suplement. St. Louis Post-Dispatch,March 26, 2002.

Anon. Kava Use Not Linked to Liver Damage, Report Says. Vitamin Retailer,April 2002.

Anon. NNFA Releases Expert Analysis of Kava Safety. Whole Foods, April 2002.

Blumenthal, Mark. The Safety of Kava Questioned. Whole Foods, March 2002.

Duke, James A. Dr. Duke’s Essential Herbs. New York: St. Martin’s Paperbacks. 2001.

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