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Kava.jpg (7154 bytes)Medicinal Parts:  The peeled, dried, cut rhizome that has been separated from the root. The fresh rhizome with the root.



Demonstrated Uses:  This herb is most commonly used to reduce tension, minor or wpe2.gif (4616 bytes)moderate anxiety, stress, and restlessness.  In one study (Warneke, 1991), Kava reduced anxiety, as measured by the Hamilton Anxiety rating scale, to a greater degree than did placebo.  Click on the image to the left to view see this effect.


wpe1.gif (6042 bytes)In a later study, Volz & Kieser (1997), compared the effects of Kava vs. placebo again using the Hamilton Anxiety rating scale as well as the SCL-90 to measure anxiety levels.  The study included 101 outpatients who exhibited a variety of minor to moderate anxiety wpe3.gif (4927 bytes)disorders, e.g., agoraphobia, specific phobia, social phobia, generalized anxiety disorder, adjustment disorder with anxiety.  For the study, which lasted 25 weeks, patients were given 90-100 mg. of dry Kava extract (70 mg. of kavalactones) per day.  The results of this study can be viewed in enlarged versions by clicking onto the small images at the left. As both images indicate, in this specific study, Kava performed better than placebo.  It should be noted, however, that Kava was not compared to an active anti-anxiety medication.

Studies exist that compare Kava with a category of anti-anxiety medications known as benzodiazepines  For example, see Lindenberg & Pitule-Schodel (1990) and Woelke (1993).  These studies did not include placebo controls.  And, it should be noted that they are found in German journals.

How it Works The kava pyrones have muscle-relaxing, anticonvulsive and antispasmodic effects (PDR, 2000).  It is thought that Kava works on the central nervous system by stimulating GABA receptors or by inhibiting Noradrenalin uptake.

Precautions:  No health hazards are known when Kava is used at the recommended dosage (PDR, 2000).  Periodic side effects that have been reported include stomach discomfort, headache, tiredness. At excessively high doses, side effects have included: extreme tiredness, "flaccidity" (looseness of the muscles), unsteadiness, appearance of inebriation, yellowing and scaling of skin.

In September,1997, the American Herbal Products Association recommended the following label warning:  "Caution: Not for use by persons under the age of 18.  If pregnant, nursing, or taking a prescription drug, consult a healthcare practitioner prior to use.  Do not exceed the recommended dosage. Excessive consumption may impair ability to drive or operate heavy equipment"

This warning is consistent with cautions published by the German Commission E.

The use of Kava in conjunction with substances that act on the central nervous system (alcohol, barbiturates,etc.) should be avoided.

Daily Dosage:  Kava should be standardized to contain a certain amount of kavalactones.  The consumer should check both the mg of Kava root extract per capsule and the percent of standardization by reading the label.  If such information is not provided on the label, DO NOT BUY THE PRODUCT.

Example: 128 mg/capsule at 55% = 70 mg of kavalactones in each capsule.

The recommended daily dosage is 210 mg.  From the example above, an individual would need to take 3 capsules/day.

It may take up to 4-6 weeks to see benefits.

Do not use for more than 3 months without consulting a healthcare practitioner.

Storage: Store at room temperature away from direct light, moisture, and heat.


The Culture of Kava

Kava is cultivated on tropical Pacific Islands including Fiji, Hawaii, Samoa, Tonga, Vanuatu and others.  (See the map to the left; click on the PACIFIC Islands and Kava.gif (27386 bytes) image to enlarge the map.) Vanuatu is considered the center of distribution since 80 of the 118 cultivated varieties occur in this island group (Foster & Tyler, 1999). Some experts believe that Kava could become Hawaii’s next important cash crop (Burlingame, Honolulu Star-Bulletin, Sept. 7, 1998).

Although they differ from community to community, various rituals or ceremonies among Pacific Islanders are associated with the consumption of Kava. Typically consumed before the evening meal, around dusk (Foster & Tyler, 1999), Kava is usually included in most social functions.  As examples:

    * It is a typical drink at weddings and funerals.

    * It is also often part of the dating ritual. A suitor takes the Kava root to the      women he is courting. As she serves it, he serenades her (Khan, Salt Lake Tribune, October 10, 1999).

    * It has often been offered to visiting dignitaries such as Pope John Paul II, Lady Bird Johnson, Queen Elizabeth II, and Hillary Rodham Clinton.


Driving and Kava

Driving and Kava--Utah:  June, 1996, a 44-year-old Salt Lake County (Utah) man was convicted of driving under the influence of Kava. He was stopped by a Utah Highway Patrol Officer because he was apparently swerving in and out of traffic lanes. When asked to step out of the car, he staggered, his speech was slurred, and he reacted slowly to the officer’s commands. When given a breath-test, his alcohol level registered zero, and there were no signs of illegal drug use. When questioned, the man said that he had spent the evening with friends drinking a Kava beverage--16 cups of it. Later, blood was drawn and laboratory tests suggested that the Kava had impaired the man’s ability to drive. This conviction was the first of its kind in the state, if not the nation (Swensen, Deseret News Archives, Salt Lake City, Utah, August 5, 1996).

Driving and Kava--California Case 1: August 7, 1999 a 47-year old San Bruno, CA man was arrested and charged with driving under the influence of Kava tea. Around 3 AM, according to CHP officers, the man was seen weaving on Highway 101 in San Mateo County. When given a field sobriety test, he failed it, but a chemical test in San Mateo County Jail revealed no traces of alcohol or other illegal drugs. The man, a native of Tonga, told investigators that he drank 8 cups of Kava tea for 6 hours during his church’s Kava circle, a social ceremony. 

This was the first time in California that someone was charged with DUI when Kava was involved. The District Attorney argued that California DUI law covers anything that might affect the brain, muscles or central nervous system and that could prevent the driver from safely operating a motor vehicle. 

Within a week of his arrest, the man was suspended without pay from his delivery job. On October 28, 2000, he was acquitted after his case ended in a mistrial (Stannard, San Francisco Chronicle, October 28, 2000). The jury was deadlocked 10-2 in favor of acquittal. He is filing a $20 million wrongful termination lawsuit against his former employer.

Driving and Kava--California Case 2On June 17, 2000, police stopped a 26-year-old man on Highway 101 near Redwood City, CA (San Mateo County) for driving erratically. The man, a native of Tonga, said that he drank 23 cups of Kava tea at a San Mateo church and when given a field sobriety test, he failed it. The San Mateo County District Attorney charged him with DUI. In November, 2000, a San Mateo County Judge dropped the charges ruling that there was not enough evidence to show that state laws against DUI included Kava tea (ContraCosta Times. com, December 29, 2000).



Burlingame, B.  (September 7, 1998). Hawaii looks to cash in on kava.  Honolulu Star-Bulletin Local News. Online  Accessed 11-9-2000.

ContraCosta Times. com (West County Times, Contra Costa County, California Editorial, December 29, 2000). Online Accessed 1/2/01.

Foster, S. & Tyler, V.E.  (1999).  Tyler's Honest Herbal. New York:  The Haworth Herbal Press.

Khan, L. (October 10, 1999). Utah Tongans wrestle a culture gap. Salt Lake Tribune. Online  Accessed 11/9/2000.

Lindenberg, V.D. & Pitule-Schodel, H. (1990).  D,L-Kavain in comparison with oxazepam in anxiety states.  Double-blind clinical trial. Fortsche Med.  Vol. 108, No. 2, 49-50; 53-54.

PDR® for Herbal Medicines. 2nd edition.  (2000).  Montvale, NJ:  Medical Economics Company.

Stannard, M.T.  (October 28, 2000). Kava-drinking case in San Bruno ends in mistrial. San Francisco Chronicle. p. A24.

Swensen, J.N. (August 5, 1996).  Man convicted of driving under influence of kava.  Deseret News Archives, Salt Lake City, Utah.  Online through the Deseret News Archives Service  Subscription required. Accessed 11/21/2000.

Volz, H.P. & Kieser, M. (1997) Kava-kava extract WS 1490 versus placebo in anxiety disorders--a randomized placebo-controlled 25-week outpatient trial.  Pharmacopsychiatry. Vol. 30, 1-5.

Warnecke, G. (1991). Psychosomatic dysfunction in the female climacteric.  Clinical effectiveness and tolerance of Kava Extract 1490. Fortsche Med. Vol. 109, No. 4, 119-122. In German.

Woelk. H. (1993).  Behandlung von Angst-Patienten. Z Allgemeinmed. Vol. 10, 271-277.