Kava Kava Root Monograph

Scientific name of Kava Kava Root:
Piper methysticum

Action of Kava Kava Root:
Natural sedative

Kava Kava Root is used for these common wellness concerns:
Occasional nervousness, nervous tension and anxiety

Clarocet blends with effects similar to Kava Kava:

An Overview of Kava Kava Root

The scientific name of Kava Kava, Piper methysticum, comes from the Greek for “intoxicating pepper.” Kava Kava has been used for centuries to promote relaxation and emotional wellbeing. This herb, native to Indonesia and other Pacific Ocean cultures, is commonly sold as an over-the-counter supplement in both the United States and Europe to provide positive support for:

  • Occasional nervousness and nervous tension
  • Mild to moderate anxiety caused by everyday stress

Studies have shown that Kava Kava provides fast-acting sedation. Its initial effects create a more relaxed, sociable state of mind and a heightening of the senses. At higher doses, Kava Kava can facilitate deep, refreshing sleep.

Science and Pharmacology of Kava Kava Root

Kavalactones are a group of compounds found in the roots and rhizomes of the Kava Kava plant, and they are considered by researchers to be the agents primarily responsible for Kava Kava’s therapeutic properties. The following six Kavalactones have been isolated and identified as the principle compounds active in Kava Kava preparations:

  • Kawain
  • Methysticin
  • Demethoxy-y
  • Dihydrokawain
  • Dihydromethysticin

These Kavalactones are believed to work by binding to various receptors in the brain, most notably in the area known as the amygdala, a brain structure which regulates fear and anxiety. Kava Kava appears to have a broad effect on the limbic system, the area of the brain responsible for emotions. Homeostatic mechanisms in the limbic system also regulate blood pressure, heart rate, blood sugar, sex drive, hunger and sleep cycles. These functions are closely related to feelings of stress, occasional anxiety and depressed mood.

Kava Kava Root Safety and Usage

Kava Kava’s safety profile is currently under consideration after it was reported to cause liver failure in a small number of individuals taking products containing Kava Kava. The Australian Therapeutic Goods Administration suggests that individuals using Kava Kava as a dietary supplement take 250 milligrams or less within any 24-hour period. Kava Kava supplements are currently available in doses of 100 milligrams, 250 milligrams, 500 milligrams, and 1000 milligrams, and they are typically standardized to between 30 and 90 percent.

What are the potential side effects of Kava Kava Root?

Side effects are rare and have been documented as mild to moderate in most cases. These may include headache, gastrointestinal discomfort, drowsiness, dizziness and sensitivity to UV light sources. More severe side effects, including liver damage and death related to liver failure have also been reported. No direct link has been established between Kava Kava products and hepatotoxicity (liver toxicity). In the event that you experience an adverse reaction, discontinue use of this herb. Kava Kava should be taken under the supervision of a professional healthcare provider.

Is Kava Kava Root safe for children?

Kava Kava use has not been studied in children and it is not recommended for children under the age of 18.

Does Kava Kava Root adversely interact with prescription drugs?

Taking Kava Kava in combination with prescription medications such as benzodiazepines, SSRIs (selective serotonin reuptake inhibitors), or SNRIs (serotonin-norephinephrine reuptake inhibitors) may cause drowsiness. If you are taking a prescription medication, it is recommended that you consult with your prescribing doctor before making any changes or additions to your current treatment plan.

What precautions should I take before beginning Kava Kava Root?

Consult with your healthcare provider before beginning a wellness plan that includes dietary supplements like Kava Kava Root.

  • Do not take Kava Kava Root if you are pregnant or nursing
  • Do not take Kava Kava Root if you are currently taking a prescription MAOI
  • Do not operate vehicles or heavy machinery until you know how Kava Kava Root affects you

Kava Kava Root Clinical Studies

Clinical Study Meta-Analysis and Peer Reviews

1. Dietary Supplements and Natural Products as Psychotherapeutic Agents
Adriane Fugh-Berman, MD and Jerry M. Cott, PhD
From the Department of Health Care Sciences (A.F.-B.), George Washington University School of Medicine and Health Sciences, Washington, DC; and Adult Psychopharmacology Program (J.M.C.), National Institute of Mental Health, Rockville, MD. Psychosomatic Medicine 61:712-728 (1999) [Read the Full Text ]

Excerpts From This Meta-Analysis:
"In a randomized, double-blind, placebo-controlled multi-center study, 101 outpatients with DSM-III-R anxiety disorders (agoraphobia, specific phobia, generalized anxiety disorder, or adjustment disorder with anxiety) were treated with the kava extract WS1490 (210 mg/d in divided doses) for 24 weeks. Results showed significant reductions in HAM-A scores in the kava group beginning in the eighth week and increasing throughout the trial. Improvements were also seen in secondary outcome variables, which included Hamilton subscale scores for somatic and psychic anxiety, the Clinical Global Impression scale, Self-Report Symptom Inventory, and the Adjective Mood scale. Side effects were greater in the placebo group than the kava group, the latter consisting of two patients with upset stomach. No changes were observed in clinical blood chemistry values, hematological parameters, or vital signs. In contrast to the benzodiazepines and tricyclics, both of which are used to treat anxiety disorders, treatment with kava did not lead to tolerance."

"In a randomized, double-blind, placebo-controlled trial, 58 patients with various ICD-diagnosed anxiety and neurotic disorders were randomly assigned to receive 70 mg of kavalactones from extract WS 1490 (Laitan) or placebo three times daily for 4 weeks. Compared with the placebo group, the kava group demonstrated a significant reduction in anxiety (assessed by HAM-A) by the end of the first week; differences between the two groups increased during the course of the study. Side effects were minimal, with the authors reporting no undesirable events."

2. Efficacy of kava extract for treating anxiety: systematic review and meta-analysis.
Pittler MH, Ernst E.
Department of Complementary Medicine, School of Postgraduate Medicine and Health Sciences, Univ. of Exeter, UK J
Clin Psychopharmacol. 2000 Feb;20(1):84-9 [Read the Abstract]

Excerpts From This Meta-Analysis:
"Eleven trials with a total of 645 participants met the inclusion criteria. The meta-analysis of six studies using the total score on the Hamilton Anxiety scale as a common outcome measure suggests a significant reduction in patients receiving kava extract compared with patients receiving placebo. The data available from the reviewed studies suggest that kava is relatively safe for short-term treatment (1 to 24 weeks)..."

3. Is kava really hepatotoxic? An analysis of the known data on adverse effects of kava preparations
Mathias Schmidt
Institute of Pharmaceutical Biology and Phytochemistry
May 2003 [Read the Full Text]

4. Kava Report 2003 - [Clinical] Investigation into EU Member States and Kava Products
J. Gruenwald, PhD, C. Mueller, PhD, J. Skrabal, MS
Phytopharm Consulting Part IIA - 4.3 March 2003 [Read the Full Text]

Clinical Trials and Laboratory Tests

1. Kava-kava extract WS 1490 versus placebo in anxiety disorders--a randomized placebo-controlled 25-week outpatient trial.
Volz HP, Kieser M.
Department of Psychiatry, Jena University
Pharmacopsychiatry. 1997 Jan;30(1):1-5. [Read the Abstract]

2. Efficacy of kava-kava in the treatment of non-psychotic anxiety, following pretreatment with benzodiazepines.
Malsch U, Kieser M.
Klinikum Nord/Ochsenzoll, Langenhorner Chaussee;
Psychopharmacology (Berl). 2001 Sep;157(3):277-83 [Read the Abstract]

3. Efficacy of a special kava extract (Piper methysticum) in patients with states of anxiety, tension, and excitedness of nonmental origin—a double-blind placebo-controlled study of four weeks treatment.
Lehmann E, Kinzler E, Friedemann J.
Phytomedicine 1996; 2: 113–9. PMID: 1930344 [Read the Abstract]

4. Kava-Kava extract LI 150 is as effective as Opipramol and Buspirone in Generalized Anxiety Disorder--an 8-week randomized, double-blind multi-centre clinical trial in 129 out-patients.
Boerner RJ, Sommer H, Berger W, Kuhn U, Schmidt U, Mannel M.
Department of Psychiatry, Ludwig-Maximilians-University, Munich, Germany. reinhard.
Phytomedicine. 2003;10 Suppl 4:38-49 [Read the Abstract]

5. Clinical efficacy of kava extract WS 1490 in sleep disturbances associated with anxiety disorders. Results of a multicenter, randomized, placebo-controlled, double-blind clinical trial.
Lehrl S.
Clinic and Polyclinic for Psychiatry and Psychotherapy of the University of Erlangen-Nuremberg, Department of Medical Psychology and Medical Sociology
Schwabachanlage 6, D-91054 [Read the Abstract]

6. Kava and valerian in the treatment of stress-induced insomnia.
Wheatley D.
Psychopharmacology Research Group, London, UK.
Phytother. Res. 2001 Sep;15(6):549-51. PMID: 11536390 [Read the Abstract]

7. Evaluation of combining kava extract with hormone replacement therapy in the treatment of postmenopausal anxiety.
De Leo V, la Marca A, Morgante G, Lanzetta D, Florio P, Petraglia F.
Department of Obstetrics and Gynecology, University of Siena,
Maturitas. 2001 Aug 25;39(2):185-8. PMID: 11514117 [Read the Abstract]

8. A systematic review of the safety of kava extract in the treatment of anxiety
Stevinson C, Huntley A, Ernst E.
Department of Complementary Medicine, University of Exeter,UK.
Drug Saf. 2002;25(4):251-61. PMID: 11994028 [Read the Abstract]

9. Drug absorption in vitro model: filter-immobilized artificial membranes. 2) Studies of the permeability properties of lactones in Piper methysticum Forst.
Avdeef A, Strafford M, Block E, Balogh MP, Chambliss W, Khan I.
Eur J Pharm Sci. 2001 Dec;14(4):271-80. PMID: 11684401 [Read the Abstract]

10. Effect of kava extract on vagal cardiac control in generalized anxiety disorder: preliminary findings.
Watkins LL, Connor KM, Davidson JR.
Duke University Medical Center, Department of Psychiatry and Behavioral Sciences
J Psychopharmacol. 2001 Dec;15(4):283-6. PMID: 11769822 [Read the Abstract]

11. Kavalactones from Piper methysticum, and their 13C NMR spectroscopic analyses.
Dharmaratne HR, Nanayakkara NP, Khan IA.
National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences
Phytochemistry. 2002 Feb;59(4):429-33. PMID: 11830162 [Read the Abstract]

12. Kavapyrone enriched extract from Piper methysticum as modulator of the GABA binding site
Jussofie A, Schmiz A, Hiemke C.
Institut fur Physiologische Chemie, Universitatsklinikum Essen.
Psychopharmacology (Berl). 1994 Dec;116(4):469-74. PMID: 7701051 [Read the Abstract]

13. The action profile of D,L-kavain. Cerebral sites and sleep-wakefulness-rhythm in animals
Holm E, Staedt U, Heep J, Kortsik C, Behne F, Kaske A, Mennicke I.
Abteilung fur Pathophysiologie, I. Medizinische Klinik Mannheim, Universitat Heidelberg, Mannheim. 1991 Jul;41(7):673-83  PMID: 1772452 [Read the Abstract]

14. Development of tolerance to kava in mice in clinical trials. Clinical and Experimental Pharmacology and Physiology
Duffield PH, Jamieson D.
School of Physiology and Pharmacology, University of NSW, Kensington, Australia.
1991; 18:571-578. PMID: 1914254 [Read the Abstract]

15. Kava Report 2003 - [Clinical] Investigation into EU Member States and Kava Products
J. Gruenwald, PhD, C. Mueller, PhD, J. Skrabal, MS
Phytopharm Consulting Part IIA - 4.3 March 2003 [Read the Full Text]

16. Kava, used traditionally and widely considered safe, is suprisingly linked to liver damage
Alan R. Gaby, MD
Bastyr University of Natural Health Sciences, Washington
General Nutrition Center - Weekly News Wire; December 13, 2001 [Read the Article]

Related online research destinations

Last Updated: February 2015 [PHMF-03-0]