Kava

Last Updated: March 6, 2024

Kava (Piper methysticum) is a plant that has had many traditional uses throughout history, especially among South Pacific Islanders. It is best known for anxiety reduction but comes with some serious safety concerns when used in excess.

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Kava is most often used for

What is kava?

Kava (Piper methysticum) is a member of the pepper family; it is traditionally consumed as an infusion of its root or other plant parts and is known for its anxiety-relieving and mildly euphoric effects. Although it is native to Oceania, kava is now found worldwide but may be restricted in some countries due to potential liver injury.

What are the known traditional, historical, and cultural uses of kava?

What forms does kava typically come in?

What are kava’s main benefits?

Kava is primarily known for its ability to reduce anxiety without impairing mental clarity, which makes it a potentially favorable alternative to other anxiolytics. Although it shows promise for short-term anxiety relief and may provide mood enhancement, its effectiveness for generalized anxiety disorder and insomnia remains mixed and requires further research.

Does kava help with mental health?

What other benefits might kava have?

What are kava’s main drawbacks?

Kava's main drawbacks include the potential for liver damage or dysfunction when it is used consistently for over a month or in high doses, as well as side effects like headaches, sedation, and diarrhea. Additionally, long-term use may lead to negative health outcomes similar to those of alcoholism, and caution is advised until kava's liver damage potential is fully assessed.

Does kava interact with any other substances?

What short-term side effects are associated with kava?

What long-term side effects are associated with kava?

How does kava work?

Kava works primarily through its bioactive compounds called kavalactones, which can cross the blood-brain barrier and influence psycho-emotional effects via various neurotransmitter signaling pathways. The effects of individual kavalactones can vary based on dosage and interactions, which makes it challenging to fully understand their effect on both humans and animal models.

What are other names for Kava?
Note that Kava is also known as:
  • Piper methysticum
  • Kava Pepper
  • Ava Pepper
  • Kava Kava
  • Intoxicating Pepper
  • Awa
  • rauschpfeffer
  • sakau
  • tonga
  • wurzelstock
  • Tangona
Dosage information

⚠️ Caution: Risk of Liver Injury

There are reports of herb-induced liver injury in kava users, especially when kava has been taken consistently for longer than a month.[1][2][3][4] Higher doses (2,000 mg/day over 4 weeks) are also associated with a reduction in cytochrome P450 (CYP450) activity, which could impair the liver’s ability to metabolize drugs, hormones, and other toxins.[5] It should be noted that liver injury has not been reported in all studies, so more research, and a healthy dose of caution, are warranted.[6][7] Clinical trials suggest that for most adults without health conditions, taking kava for less than one month is generally well tolerated when good-quality supplements are used.[8]

No optimal dosages or durations for kava consumption have been determined at this point.[8] Kava dosing, especially in standardized formulations, may be done with reference to the kavalactone (specifically, kavapyrone; all known kavalactones are pyrones) content. Clinical trials have used dosages ranging from 100 to 400 mg/day of kava, and from 60 to 630 mg of kavalactones, per day.[9][10][11][12][13]

As with any plant or herbal preparation, factors such as plant part, growth conditions, and extraction methods may affect the bioactivity of kava supplements. Ideally, supplements will identify a standardized kavalactone content to improve consistency of results.[14][15][16][17][18][19] There appears to be some potential for substance abuse of kava, but when it is taken at the more commonly seen dosages, this is rare.[20]

Some of kava’s active ingredients may be secreted in breast milk. Since the effects of kava in infants are still not known, use of kava while pregnant or breastfeeding is not advised.[21]

Kava may also interact with other substances like alcohol and St. John’s wort, possibly amplifying both positive and negative effects.[22][23][24][25] Reports of these interactions are varied, though, and may depend on circumstances such as dose, timing, format, and external factors.[26][27] Therefore, combination therapies that include kava should be considered with caution.

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References
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Examine Database References
  1. Subjective Well-Being - Volz HP, Kieser MKava-kava extract WS 1490 versus placebo in anxiety disorders--a randomized placebo-controlled 25-week outpatient trialPharmacopsychiatry.(1997 Jan)
  2. Subjective Well-Being - Gastpar M, Klimm HDTreatment of anxiety, tension and restlessness states with Kava special extract WS 1490 in general practice: a randomized placebo-controlled double-blind multicenter trialPhytomedicine.(2003 Nov)
  3. Subjective Well-Being - Malsch U, Kieser MEfficacy of kava-kava in the treatment of non-psychotic anxiety, following pretreatment with benzodiazepinesPsychopharmacology (Berl).(2001 Sep)
  4. Anxiety Symptoms - Pittler MH, Ernst EKava extract for treating anxietyCochrane Database Syst Rev.(2003)
  5. Anxiety Symptoms - Lehrl SClinical efficacy of kava extract WS 1490 in sleep disturbances associated with anxiety disorders. Results of a multicenter, randomized, placebo-controlled, double-blind clinical trialJ Affect Disord.(2004 Feb)
  6. Anxiety Symptoms - Geier FP, Konstantinowicz TKava treatment in patients with anxietyPhytother Res.(2004 Apr)
  7. Anxiety Symptoms - Zhang W, Yan Y, Wu Y, Yang H, Zhu P, Yan F, Zhao R, Tian P, Wang T, Fan Q, Su ZMedicinal herbs for the treatment of anxiety: A systematic review and network meta-analysis.Pharmacol Res.(2022-May)
  8. Anxiety Symptoms - Pittler MH, Ernst EEfficacy of kava extract for treating anxiety: systematic review and meta-analysis.J Clin Psychopharmacol.(2000-Feb)
  9. Anxiety Symptoms - Connor KM, Davidson JRA placebo-controlled study of Kava kava in generalized anxiety disorderInt Clin Psychopharmacol.(2002 Jul)
  10. Anxiety Symptoms - Sarris J, Kavanagh DJ, Byrne G, Bone KM, Adams J, Deed GThe Kava Anxiety Depression Spectrum Study (KADSS): a randomized, placebo-controlled crossover trial using an aqueous extract of Piper methysticumPsychopharmacology (Berl).(2009 Aug)
  11. Stress Signs and Symptoms - D WheatleyKava and valerian in the treatment of stress-induced insomniaPhytother Res.(2001 Sep)
  12. Stress Signs and Symptoms - Cropley M, Cave Z, Ellis J, Middleton RWEffect of kava and valerian on human physiological and psychological responses to mental stress assessed under laboratory conditionsPhytother Res.(2002 Feb)
  13. Reaction Time - Thompson R, Ruch W, Hasenöhrl RUEnhanced cognitive performance and cheerful mood by standardized extracts of Piper methysticum (Kava-kava)Hum Psychopharmacol.(2004 Jun)