Common Names: kava, kava kava, ava pepper, ava root, kawa
Latin Names: Piper methysticum
- Kava is native to the islands of the western Pacific and is a member of the pepper family.
- Pacific islanders have used kava for thousands of years as a medicine and for ritual purposes.
- Today, kava is promoted as a dietary supplement for anxiety, insomnia, and other conditions.
How Much Do We Know?
- There has been a fair amount of research in people on the use of kava for anxiety, but few studies have been done on other conditions.
What Have We Learned?
- Kava supplements may have a small effect on reducing anxiety, but they have been linked to a risk of severe liver injury.
- There isn’t enough evidence to show whether kava is helpful for any other conditions.
What Do We Know About Safety?
- The use of kava has been linked to liver injury that is sometimes serious or even fatal. The exact cause and frequency of the liver damage are unclear.
- Kava can cause digestive upset, headache, dizziness, and other side effects. The use of kava may affect the ability to drive or operate machinery. Long-term use of high doses of kava may cause kava dermopathy, a condition that involves dry, scaly, flaky skin with a yellow discoloration.
- Kava may have special risks if taken during pregnancy or while breastfeeding because of the presence of harmful pyrone constituents.
Keep in Mind
- Take charge of your health—talk with your health care providers about any complementary health approaches you use. Together, you can make shared, well-informed decisions.
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- Becker MW, Lourençone EMS, De Mello AF, et al. Liver transplantation and the use of kava: case report. Phytomedicine. 2019;56:21-26.
- Kava kava. LiverTox: clinical and research information on drug-induced liver injury. Bethesda, MD: National Institute of Diabetes and Digestive and Kidney Diseases; 2018.
- Kava. Natural Medicines website. Accessed at naturalmedicines.therapeuticresearch.com on January 22, 2020. [Database subscription].
- Kim J, Lee SL, Kang I, et al. Natural products from single plants as sleep aids: a systematic review. Journal of Medicinal Food. 2018;21(5):433-444.
- Pittler MH, Ernst E. Kava extract versus placebo for treating anxiety. Cochrane Database of Systematic Reviews. 2003;(1):CD003383 [edited 2010]. Accessed at www.thecochranelibrary.com on March 6, 2020.
- Sarris J. Herbal medicines in the treatment of psychiatric disorders: 10-year updated review. Phytotherapy Research. 2018;32(7):1147-1162.
- Sarris J, Stough C, Bousman CA, et al. Kava in the treatment of generalized anxiety disorder. A double-blind, randomized, placebo-controlled study. Journal of Clinical Psychopharmacology. 2013;33(5):643-648.
- Smith K, Leiras C. 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. 2018;33:107-117.
- White CM. The pharmacology, pharmacokinetics, efficacy, and adverse events associated with kava. Journal of Clinical Pharmacology. 2018;58(11):1396-1405.
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