Kava Kava

Botanical Description & Habitat

Piper methysticum

Family

Piperaceae

Common Names

        Kava
        Kawa kawa
        Methysticum
        Yungona (Fijii)


Habitat

South Sea Islands, Hawaii to East Indies, Polynesia, Melanesia

Medicinal Parts

Peeled, dried rhizome and root

Historical Properties & Uses

Kava kava has been called: "the official drink of the Pacific". The drink formed part of their traditional religious ceremonies, while today, there are Kava bars on some islands. A few cupfuls may provide a "high", or state of euphoria of short duration, accompanied by tranquility and friendliness. Unlike alcohol, there is no hangover and the mind remains clear. LIke alcohol, it is soporific, although it causes a deep, dreamless sleep.

The rhizome is chewed or ground up to make a mash, saliva is added on chewing, causing enzymatic degradation to a fully intoxicating substance. The drink causes calmness and relaxation, with enhanced mental activity.

The liquid is a greyish-greenish-brown color.

It is intoxicating, stimulating and psychoactive, although legal, a "natural high". Kava kava appears to have a mildly narcotic action. It further is said to be analgesic, anticonvulsive, antifungal, sleep-inducing, and spasmolytic, antiseptic, aromatic, diuretic, expectorant, galactagogue, sudorific and tonic.

It is claimed to sharpen mental faculties.

It is popular as a pain reliever, including headaches, and muscle relaxer.

Homeopathically, it is also used for headache and neurasthenia.

This herb has approval status by the German Commission E for conditions of anxiety or stress.

References:

Blumenthal, M (Ed.): The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. American Botanical Council. Austin, TX. 1998.

Method of Action

Kava Kava has Central Nervous System Action

The active constituents in the root are lactones called kava pyrones: kavaine, dihydrokavaine, methysticin, dihydromethysticin and yangonin which in rising doses depress the central nervous system at the level of the reticular formation of the brain stem, and relax the skeletal muscles.

Full consciousness is retained even after taking fatal doses. As the drug is eliminated via the kidneys, it produces an endoanesthetic effect on the gastric mucosa and the mucosa of the bladder. This latter effect is capitalized upon in a number of European drugs using kava kava to eliminate painful bladder syndromes. One such drug combines kava kava with pumpkin seeds and hops.

In one study, the drink affected several parameters of vision: it reduced near point of accommodation and convergence; and it caused an increase in pupil diameter and a disturbance to the oculomotor balance.

The British Herbal Pharmacopoeia recognizes it as antimicrobial, diuretic, spasmolytic, sedative, carminative and as a topical rubefacient, for use in the treatment of cystitis, urethritis, rheumatism, joint pains (topical); specific indication is infection of genitourinary tract. Combined with marshmallow, celery seed and couchgrass in bladder disease; with buck bean, black cohosh and celery seed in rheumatism.

Drug Interactions & Precautions

Known Interactions

Insofar as diuretic action, Kava Kava increases the renal excretion of sodium and chloride, which may potentiate the hyperglycemic and hyperuremic effects of glucose elevating agents.

Possible Interactions

Kava kava's analgesic effects may be additive with other analgesics and anesthetics. It may be inhibited by barbiturates even though CNS depressant effects may occur.

The analgesic property of this herb may be reversed or eliminated by p-chlorophenylalanine, cyproheptadine HCl, and phenobarbital.

The CNS depressant tendency of this analgesic may be potentiated by chlorproxthixene HCl, haloperidol, and tranquilizers.

The antacid nature of kava kava may decrease or delay the absorption of nalidixic acid and the sulfonamides.

Due to the spasmolytic nature of kava kava it may interact in unknown ways with CNS depressants or stimulants.

The use of diuretics may require dosage adjustments of antidiabetic drugs.

Kava kava should not be used with methotrimeprazine, a potent CNS depressant analgesic.

The German Commission E notes the possibility for kava to be potentiated by substances which act on the central nervous system e.g. alcohol, barbiturates and psychopharmacological agents.

Comments

In the absence of other hard data, it may still be assumed observable interactions may occur between the many central nervous system drugs and the psychoactive principles in this herb.

References:

Blumenthal, M (Ed.): The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. American Botanical Council. Austin, TX. 1998.

Safety Factors & Toxicity

Kava Kava Does not appear to be a narcotic, though opinion is divided on this point. Continued use may cause inflammation of body and eyes, resulting ulcers, parching, peeling of skin.

The FDA has determined kava kava resin acts on the spinal column. Kava may produce unknown damage to the liver.

Avoid driving while under the influence of kava.

This herb has approval status by the German Commission E for anti-anxiety and as an anticonvulsant.

The German Commission E recommends a limited duration for the use of this herb of 3 months, unless specified by a physician.

References:

Blumenthal, M (Ed.): The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. American Botanical Council. Austin, TX. 1998.

Preparation & Administration

Use three times daily

Decoction
Use 2-4g of dried root

Liquid Extract
Use 2-4ml

This herb has approval status by the German Commission E.

Recommended daily dosages in Germany are as follows:

Herb and preparations equivalent to 60 - 120 mg kava pyrones.

The German Commission E recommends a limited duration for the use of this herb of 3 months, unless specified by a physician.

References:

Blumenthal, M (Ed.): The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. American Botanical Council. Austin, TX. 1998.

Abstracts

References

Almeida JC; Grimsley EW: Coma from the health food store: interaction between kava and alprazolam. [letter] Ann Intern Med, 1996 Dec, 125:11, 940-1.

Anonymous: Kava. Lancet, 1988 Jul 30; 2 (8605): 258-9.

Blumenthal, M (Ed.): The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. American Botanical Council. Austin, TX. 1998.

Braun, H. & Frohne, D. Heilplanzen-Lexikon Fuer Aerzte und Apotheker. Gustav Fisher Verlag, Stuttgart, New York, 1987.

British Herbal Pharmacopoeia, British Herbal Medicine Association, 1983.

Backhauss C; Krieglstein J Extract of kava (Piper methysticum) and its methysticin constituents protect brain tissue against ischemic damage in rodents. European Journal of Pharmacology 1992; 215 (2-3): 265-9.

Capasso, A., Pinto, A. Experimental investigations of the synergistic-sedative effect of passiflora and kava. Acta Therapeutica. 21 (2) (1995): 127-140.

Cawte, J. Psychoactive substances of the South Seas: betel, kava and pituri. Australian and New Zealand Journal of Psychiatry 1985; 19 (1): 83-7.

Davies, L., Drew, C., Duffield, P., Johnston, G., Jamieson, D. Kava pyrones and resin: studies on GABAA, GABAB, and benzodiazepine binding sites in rodent brain. Pharmacology and Toxicology. 71 (1992): 120-126.

Duke, J.A. CRC Handbook of Medicinal Herbs, CRC Press, Inc., Boca Raton, Florida, 1985.

Garner, L.F. & J.D. Klinger. Some visual effects caused by the beverage Kava. Journal of Ethnopharmacology, 13(3), 307-311, 1985.

Gruenwald, J, Brendler, T & Jaenicke, C (Eds.): PDR for Herbal Medicines. Medical Economics, NJ. 1998.

Kinzler E; Kromer J; Lehmann E [Effect of a special kava extract in patients with anxiety-, tension-, and excitation states of non-psychotic genesis. Double blind study with placebos over 4 weeks]. Wirksamkeiteines Kava-Spezial-Extraktes bei Patienten mit Angst-, Spannungs-, und Erregu ngszustanden nicht-psychotischer Genese. Doppelblind-Studie gegen Plazebo uber 4 Wochen. Armeimittelforschung , 199 1; 41 (6): 5 84-8.

Lebot, V.; Merlin, M. and Lindstrom, L. : Kava: the Pacific Drug. Yale UP, New Haven, CT. 1992.

Mowrey, Daniel B., Ph.D. Exper. Psych., Brigham Young University. Director of Nebo Institute of Herbal Sciences. Director of Behavior Change Agent Training Institute. Director of Research, Nova Corp.

Munte, T. F., Heinze, H. J., Matzke, M., and Steitz, J. Effects of Oxazepam and an Extract of Kava Roots (Piper methysticum) on Event-Related Potentials in a Word Recognition Task. Neuropsychobiology. 1993:27(l): 46-53

Norton, S. A.; Ruze, P. Kava dermopathy. Journal of the American Academy of Dermatology. 1994; 31 (1): 89

Raffauf, C., jendroska, K., Poewe, W Kava and dopamine antagonism. Journal of Neurology, Neurosurgery, and Psychiatry. Vol. 58 (1995): 639-640.

Singh, Y. N. Kava: an overview. Journal of ethnopharmacology. 1992; 37(l): 13-46.
Volz HP & Kieser M: Kava-kava extract WS 1490 versus placebo in anxiety disorders--a randomized placebo-controlled 25-week outpatient trial. Pharmacopsychiatry, 1997 Jan, 30:1, 1-5.

Weiss, R.F. Herbal Medicine. Beaconsfield Publishers, LTD, Beaconsfield, England, 1988.