Principal Proposed Uses
Other Proposed Uses
Kava is a member of the pepper family that has long been cultivated by Pacific Islanders for use as a social and ceremonial drink. The first description of kava came to the West from Captain James Cook on his celebrated voyages through the South Seas. Cook reported that on occasions when village elders and chieftains gathered together for significant meetings, they would hold an elaborate kava ceremony. Typically, each participant would drink two or three bowls of chewed kava mixed with coconut milk. Kava was also drunk in less formal social settings as a mild intoxicant. When they learned about kava's effects, European scientists set to work trying to isolate its active ingredients. However, it wasn't until 1966 that substances named kavalactones were isolated and found to be effective sedatives. One of the most active of these is dihydrokavain, which has been found to produce a sedative, painkilling, and anticonvulsant effect. 1,2,3 Other named kavalactones include kavain, methysticin, and dihydromethysticin. High doses of kava extracts are thought to cause muscle relaxation and even paralysis (without loss of consciousness) at very high doses. 4-7 Kava also has local anesthetic properties, producing peculiar numbing sensations when held in the mouth. The method of action of kava is not fully understood. Conventional tranquilizers in the Valium family interact with special binding sites in the brain called GABA receptors. Early studies of kava suggested that the herb does not affect these receptors. 8 However, more recent studies have found an interaction. 9,10 The early researchers may have missed the connection because kava appears to affect somewhat unusual parts of the brain. Note : An accumulation of case reports suggests that kava products may rarely cause severe liver injury, and this has led to a banning of kava by many countries. See Safety Issues for more information.