Omnia SanaCommon names in 20 European languages →
The complete database record: 2 documented constituents, 2 pharmacological actions, 4 traditional / indicated uses, with 13 cited sources.
Botanical Description
Robust, shrubby perennial with thick, jointed, cane-like stems and large, heart-shaped, glossy green leaves. The plant rarely if ever flowers or sets viable seed in cultivation and is propagated entirely by stem cuttings; the thick, knotty underground rhizome and root, the medicinal part, contains the characteristic kavalactone-rich resin.
Habitat & Distribution
Native to the islands of the South Pacific (Vanuatu, Fiji, Tonga, Samoa and neighbouring islands); cultivated in warm, humid, shaded tropical conditions.
Harvesting
The root and rhizome are dug from plants at least three to five years old, when kavalactone content is highest, then cleaned, peeled and dried or processed fresh into a beverage.
Key Constituents
Lipophilic lactones concentrated in the root/rhizome; regarded as the main anxiolytic constituents, acting on GABA-A signalling and other CNS targets.
Chalcone-type constituents of the root; implicated by structure-activity analyses as the components most likely responsible for kava-associated liver injury, which is why water-based extracts of peeled noble-cultivar root are preferred.
Pharmacological Actions
Standardised kava extracts significantly reduce anxiety versus placebo in controlled trials (Hamilton Anxiety scale).
Traditional & Indicated Uses
inferred from anxiolytic action
Directly measured as a treatment target in a 156-patient observational trial of kava extract, where nervous tension and restlessness showed the largest improvements.
inferred from sedative action
more plants for insomnia / sleeplessness →detailed sources →
Traditional Use & History
Kava root has a centuries-long ceremonial and social tradition across Pacific Island cultures, prepared as a communal beverage for its calming, sociable and relaxing effects; this traditional anxiolytic reputation is now supported by clinical trials of standardised water-based extracts for anxiety.[6]
Preparations
Peeled root pounded or ground and mixed with water, strained and drunk fresh, the traditional Pacific Island ceremonial and social preparation.
Water-based extract standardised to kavalactone content, taken as capsules; the form used in most clinical anxiety trials, and the safer choice given documented hepatotoxicity concerns with some solvent-extracted products.
Dosage
Clinical trials for anxiety commonly use extracts providing up to around 250 mg kavalactones daily, from water-based extracts of peeled root of a noble cultivar, for short-term use only, given the rare but serious hepatotoxicity risk. Educational reference only, not a prescription.
Safety, Cautions & Contraindications
Rare but serious drug-induced liver injury (hepatitis, cirrhosis, liver failure) has been reported with kava; it is contraindicated in people with liver disease and should not be combined with alcohol or other medicines that can harm the liver. To reduce risk, use only water-based extracts of peeled root/rhizome from a noble cultivar, keep the dose at or below about 250 mg kavalactones per day, and use short-term only. Stop and seek care for signs of liver trouble (dark urine, jaundice, nausea, abdominal pain).
Kavalactones inhibit several cytochrome P450 enzymes (CYP1A2, 2C9, 2C19, 2D6 and 3A4), which metabolise a large share of prescription medicines. Kava may therefore raise blood levels of such drugs; check with a pharmacist or doctor before combining kava with any regular medication.
Herb-Drug Interactions
Herb-Herb Pairings
Kava and valerian are both calming, sedating herbs; taken together they may add up to cause excessive drowsiness, so use caution and avoid before driving or combining with other sedatives.
Kava and passionflower are both relaxing, sedating herbs; combined use may deepen drowsiness and sedation, so use caution.
Botanical Synonyms
Macropiper methysticum
Harvest Readiness
[9]
[9]
External Identifiers
References & Sources
- Block, K.I., Gyllenhaal, C. and Mead, M.N (2004) 'Safety and efficacy of herbal sedatives in cancer care', Integrative Cancer Therapies, 3(2), pp. 128-148. doi:10.1177/1534735404265003 Meta-analysis / review
https://doi.org/10.1177/1534735404265003 - Pittler, M.H. and Ernst, E (2000) 'Efficacy of kava extract for treating anxiety: systematic review and meta-analysis', Journal of Clinical Psychopharmacology, 20(1), pp. 84-89. doi:10.1097/00004714-200002000-00014 Meta-analysis / review
https://doi.org/10.1097/00004714-200002000-00014 - Smith, K. and Leiras, C (2018) 'The effectiveness and safety of Kava Kava for treating anxiety symptoms: A systematic review and analysis of randomized clinical trials', Complementary Therapies in Clinical Practice, 33, pp. 107-117. doi:10.1016/j.ctcp.2018.09.003 Meta-analysis / review
https://doi.org/10.1016/j.ctcp.2018.09.003 - Zhang, W., Yan, Y., Wu, Y., Yang, H., Zhu, P., Yan, F., Zhao, R., Tian, P., Wang, T., Fan, Q. and Su, Z (2022) 'Medicinal herbs for the treatment of anxiety: A systematic review and network meta-analysis', Pharmacological Research, 179, pp. 106204. doi:10.1016/j.phrs.2022.106204 Meta-analysis / review
https://doi.org/10.1016/j.phrs.2022.106204 - Sarris, J (2018) 'Herbal medicines in the treatment of psychiatric disorders: 10-year updated review', Phytotherapy Research, 32(7), pp. 1147-1162. doi:10.1002/ptr.6055 Meta-analysis / review
https://doi.org/10.1002/ptr.6055 - Pittler, M.H. and Ernst, E (2003) 'Kava extract for treating anxiety', Cochrane Database of Systematic Reviews, 2003(1), pp. CD003383. doi:10.1002/14651858.CD003383 Meta-analysis / review
https://doi.org/10.1002/14651858.CD003383 - Teschke, R., Qiu, S.X., Xuan, T.D. and Lebot, V (2011) 'Kava and kava hepatotoxicity: requirements for novel experimental, ethnobotanical and clinical studies based on a review of the evidence', Phytotherapy Research, 25(9), pp. 1263-1274. doi:10.1002/ptr.3464 Meta-analysis / review
https://doi.org/10.1002/ptr.3464 - Wang, Yingli and Su, Chao and Zhang, Bo and Niu, Yang and Ren, Ruru and Zhao, Xiaojun and Yang, Lingling and Zhang, Wannian and Ma, Xueqin (2021) 'Biological Activity, Hepatotoxicity, and Structure-Activity Relationship of Kavalactones and Flavokavins, the Two Main Bioactive Components in Kava (Piper methysticum)', Evidence-Based Complementary and Alternative Medicine, 2021, pp. 6851798. doi:10.1155/2021/6851798 Meta-analysis / review
https://doi.org/10.1155/2021/6851798 - Fern, Ken 'Piper methysticum (Useful Tropical Plants)'. Available at: https://tropical.theferns.info/viewtropical.php?id=Piper+methysticum Traditional / reference
https://tropical.theferns.info/viewtropical.php?id=Piper+methysticum - Sarris, J., Kavanagh, D.J., Adams, J., Bone, K. and Byrne, G (2009) 'Kava Anxiety Depression Spectrum Study (KADSS): a mixed methods RCT using an aqueous extract of Piper methysticum', Complementary Therapies in Medicine, 17(3), pp. 176-178. doi:10.1016/j.ctim.2009.01.001 Randomized trial
https://doi.org/10.1016/j.ctim.2009.01.001 - Kuchta, Kenny and Hladikova, Marie and Thomsen, Michael and Nahrstedt, Adolf and Schmidt, Mathias (2020) 'Kava (Piper methysticum) Extract for the Treatment of Nervous Anxiety, Tension and Restlessness', Drug Research, 71(2), pp. 83-93. doi:10.1055/a-1268-7135 Clinical study
https://doi.org/10.1055/a-1268-7135 - Anke, Jennifer and Ramzan, Iqbal (2004) 'Pharmacokinetic and pharmacodynamic drug interactions with Kava (Piper methysticum Forst. f.)', Journal of Ethnopharmacology, 93(2-3), pp. 153-160. doi:10.1016/j.jep.2004.04.009 Meta-analysis / review
https://doi.org/10.1016/j.jep.2004.04.009 - Pittler, M.H. and Ernst, E (2003) 'Kava extract for treating anxiety', Cochrane Database of Systematic Reviews, 2003(1), pp. CD003383. doi:10.1002/14651858.CD003383 Meta-analysis / review
https://doi.org/10.1002/14651858.CD003383
Selected studies & references
All 12 studies in the Knowledge Finder →
This profile is assembled automatically from the Omnia Sana plant database, which we curate by hand. How this site is built.