Please note that Kava has been implicated in potential liver toxicity. Please see the FDA's Posting.

Kava is an herb derived from the root of a plant that is indiginous to Polynesia. It no longer seeds and propagates itself, requiring human intervention to sprout roots, and replant it. Kava can be quite effective for relaxation, and has been shown to be effective in both a placebo controlled trial and a comparative trial using a benzodiazepine (this class of drugs includes valium, klonopin and xanax). Nervenarzt 65(1 Suppl):1-4, 1994, Drug Therapy of Panic Disorders. Kava-specific Extract WS 1490 Compared to Benzodiazepines AND Pharmacopsychiatry 30: 1-5, 1997, Kava-kava Extract WS 1490 versus Placeboin Anxiety Disorders-A Randomized Placebo-controlled 25-week Outpatient Trial. The active ingredients are the Kava lactones, and the mixture of the 6 active lactones is important (a lactone refers to a certain ringed organic chemical structure). The usual dose of Kava is 75 mg of Kava lactones three times a day (usually a 250mg capsule containing 30% Kava lactones). Thisis the dose used in the studies cited above.

Few side effects have been reported with Kava, however, evaluation for safety in thousands of people has not been done to date. Sedation (feeling tired) is quite uncommon with Kava alone. However, when Kava is taken in conjunction with benzodiazepines (the valium like medications noted above), sedation may be enhanced. Kava should not be taken with alcohol, as not only is the risk of sedation increased, but the degree of intoxication also may be increased (Drug and Alcohol Reveiws, 16: 147-155, 1997). Mild elevations of liver function tests (transaminases) can occur (<5%) (CNS Spectrums 6: 848-853, 2001). On 19 December 2001, the FDA released a MedWatch alert about at least 25 cases of liver toxicity associated with Kava that had been reported in Europe.

Kava should be used only under a physician's supervision in people without known liver disease. Kava abuse has been rare, but reported. Excessive use (grams of Kava daily) has been associated with intoxication, extreme fatigue and unsteadiness. Prolonged use at high doses can lead to thickened, yellow skin, which has been reversible when Kava is stopped (Journal of the American Academy of Dermatology, 31: 89-97, 1994). However, when kava is taken at a dose comparable to that used in the controlled studies noted above (e.g. 250 mg of a kava preparationthat is 30% kavalactones), side effects are quite unusual. Serial liver function tests should be performed in anyone taking Kava on a regular basis.

The usual dose of Kava is one 250 mg capsule (containing 75 mg of kava lactones) three times daily, as needed for anxiety and/or relaxation. If you are anxious in the evening, and have trouble sleeping due to an active mind, you may benefit from taking two capsules of the above preparation in the evening. Kava is generally not sedating, so it aids in sleep only be relaxing you. There are a couple reports in the literature (one from 1983 in the Journal of Ethnopharmacology and one from1969 in a German Journal) showing Kava's effectiveness in relaxing muscles. This is an interesting use of Kava, especially since current medical therapies for muscle spasm are often not helpful and/or not tolerated. My experience when using Kava for muscle spasm is limited (a dozen or so patients), but it hasn't demonstrated a clear benefit (you always expect one or two people to have a benefit to a treatment, even if it isn't directly due to the treatment, per se).

Since there is no governmental regulations regarding herbal therapies,one is left to the discretion of the manufacturer. I had good success with patients using the Forest Walker brand of Kava Kava. However, this product was bought out by Doctor's A-Z, and renamed, "Supreme Kava Kava". A general recommendation is to be brand specific when using herbs, due to the poor regulation of this industry. I have had good success when patients have used these products, but there may well be other brands of Kava that also work well. However, it is possible that this brand will be come unavailable or replaced by a similar product from the same manufacturer. I can make no other recommendations about a particular Kava product at this time. As with all Dietary Supplements, there is a USP standard, and this should be sought by all consumers of such products.