Kava (Piper methysticum G. Forst)

background

Drinks made from the dried roots of the kava shrub have been used in the South Pacific for hundreds of years and in Europe since the 1700s. The drink is reported to have pleasant mild effects similar to those of alcoholic drinks. Kava use has spread in Aboriginal communities in Australia over the last 20 years, where it is often combined with alcohol. In Fiji, kava is still used during welcome and religious ceremonies.
Studies report that kava may help treat anxiety in as few as 1-2 doses, with continued improvements over 1-4 weeks. Early evidence suggests that kava may be as effective as antianxiety drugs like benzodiazepines. Kava preparations were widely used in Europe and the United States to relieve anxiety but have been withdrawn in several European markets and Canada due to safety concerns.
There is promising evidence supporting the use of kava in improving cognition, depression, and hot flashes. More research is needed to make firm conclusions.
Kava has been used as a treatment for insomnia. However, many experts believe that kava may lack effectiveness for this purpose. Chronic or heavy use of kava has been linked to changes in the nervous system or skin, as well as high blood pressure in the lung arteries.
There is widespread concern that kava may be harmful to the liver. More than 30 cases of liver damage have been reported in Europe, including liver swelling, inflammation, scarring, dysfunction, and failure, as well as some reports of death. However, some experts maintain that kava is safe in most people when used in recommended doses. It is unclear what dose or length of use may be lead to liver damage. This remains an area of controversy.

Related Terms

11-Methoxy-5,5-hydroxydihydrokawain, 6-dihydroyangonin, alkaloids, antares, ava, ava pepper, ava pepper shrub, ava root, awa, bornyl cinnamate, Cavain, chalcone methylesters, desmethoxyyangonin, dihydrokavain, dihydrokawain (DHK), dihydromethysticin (DMH), (+)-dihydrokawain-5-ol, Fijian kava, flavokavine A, flavokavine B, flavonoids, gea, gi, grog, intoxicating long pepper, intoxicating pepper, kao, kava kava extract LI 140, kava kava rhizome, kava root, kavain, kavakava, kavalactones, kavapiper, kavapyrones, kavarod, kavasporal forte, kave-kave, kawa, kawa kawa, kawa pepper, Kawa Pfeffer, kawain, kew, lactones, LI150, long pepper, Macropiper latifolium, malohu, maluk, maori kava, meruk, methysticin, milik, pepe kava, Piper methysticum, Piper methysticum G.Forst, Piperis methystici rhizoma, pipermethystine, pyrones, Rauschpfeffer, rhizoma Piperis methystici, Rhizome Di Kava-Kava sakaua, sakau, tonga, WS 1490, wurzelstock, yagona, yangona, yangonin, yaqona, yongona.

evidence table

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
 
Anxiety (Grade: A)
Many studies report that kava is moderately effective for relieving anxiety. Kava has been found to promote significant improvement of anxiety symptoms. Early evidence suggests that kava may be as effective as antianxiety drugs like benzodiazepines. Kava's effects may be similar to the prescription drug buspirone (Buspar®). The German expert panel Commission E has approved kava for anxiety, stress, and restlessness.
Cognition (Grade: C)
There are conflicting results on the effectiveness of kava for cognitive aspects such as memory, attention, and reaction time. It has been suggested that kava may not have sedative effects at recommended doses, which may be an advantage over some drugs. There is early evidence that kava may improve mental performance. More research is needed before firm conclusions can be made.
Depression (Grade: C)
There is some evidence that kava may help relieve depression. Kava has been used in combination with St. John's wort in people with depression and anxiety. Further research is needed in this area.
Hot flashes (Grade: C)
Early study suggests that kava may significantly improve hot flashes, compared to placebo. High-quality research is needed before conclusions can be made.
Insomnia (Grade: C)
There have been some reports that kava may have sedative effects. However, there is conflicting evidence. Some studies have found a lack of sedation with kava use. Early research reported that kava lacked significant effects in people with insomnia. More research is needed to determine whether kava is effective for this condition.
Stress (Grade: C)
Early research suggests that kava and valerian may improve health by reducing stress and insomnia caused by stress. More research is needed to confirm these results.
Parkinson's disease (Grade: D)
It is unclear whether kava is safe or effective for use in people with Parkinson's disease. Kava may increase periods of reduced mobility in people taking levodopa and may cause a semicomatose state when levodopa is taken with alprazolam. More research is needed in this area to make a firm conclusion.