Kava
Kava is studied for anxiety relief. Liver toxicity risk means quality and dosing matter.
Overview
What is kava?
Kava is a drink made from the Piper methysticum plant.
Dosage
The optimal dose of kava is unknown, however studies use dosages ranging from 100-400 mg/day.
Kava interacts with many substances including alcohol.
Effect graph
Effect heatmap
SupplementDEX Database
7 conditions for and rated at least stars. All purchase bands. No minimum star filter.
Database Snapshot
Most kava research is concentrated in a handful of conditions.
- Anxiety accounts for 30 of 67 studies (45%).
- Cognitive performance accounts for 13 of 67 studies (19%).
- Generalised anxiety disorder (GAD) accounts for 12 of 67 studies (18%).
- Sparse coverage remains for Cancer, Menopause.
Safety
Dose windows
Long-term
Kava may cause liver toxicity or death when used long-term.
Special populations
Pregnancy & breastfeeding
AvoidKava should not be used by pregnant or lactating women.
Frequently Asked Questions
References
Sources26 references
SupplementDEX uses only high-quality sources to determine supplement effectiveness.
SupplementDEX Database · Anxiety
26 references1.SupplementDEX Database: Anxiety — Clinician guidelines for the treatment of psychiatric disorders with nutraceuticals and phytoceuticals: The World Federation of Societies of Biological Psychiatry (WFSBP) and Canadian Network for Mood and Anxiety Treatments (CANMAT) Taskforce2022
WFSBP/CANMAT 2022 guidelines rated acetyl-L-carnitine as not recommended for ADHD based on Grade A evidence from meta-analyses and RCTs.
2.SupplementDEX Database: Anxiety — Medicinal herbs for the treatment of anxiety: A systematic review and network meta-analysis2022
A network meta-analysis of medicinal herbs for anxiety found ginkgo biloba among herbs with significant HAMA score reductions versus placebo, though evidence quality varied.
19.SupplementDEX Database: Anxiety — Plant-based Medicines (Phytoceuticals) in the Treatment of Psychiatric Disorders: A Meta-review of Meta-analyses of Randomized Controlled Trials2021
A meta-review of 9 phytoceutical meta-analyses (5,927 participants) found supportive evidence for St John's wort, curcumin, and saffron in depression and ginkgo in schizophrenia negative symptoms; kava was not effective for diagnosed anxiety disorders.
20.SupplementDEX Database: Anxiety — Kava for generalised anxiety disorder: A 16-week double-blind, randomised, placebo-controlled study2020
In 171 adults with generalized anxiety disorder, kava 120 mg kavalactones twice daily for 16 weeks did not reduce anxiety versus placebo and caused more memory problems and liver test abnormalities.
3.SupplementDEX Database: Anxiety — The effectiveness and safety of Kava Kava for treating anxiety symptoms: A systematic review and analysis of randomized clinical trials2018
A systematic review of 11 kava RCTs (330 participants) found kava more effective than placebo for anxiety (RR 1.50) with comparable adverse events, though liver toxicity concerns remain for long-term use.
21.SupplementDEX Database: Anxiety — Kava in the treatment of generalized anxiety disorder: a double-blind, randomized, placebo-controlled study2013
In 75 adults with generalized anxiety disorder, kava 120–240 mg kavalactones/day for 6 weeks reduced HAMA scores versus placebo (p=0.046) with 26% remission versus 6% on placebo.
4.SupplementDEX Database: Anxiety — The acute effects of kava and oxazepam on anxiety, mood, neurocognition; and genetic correlates: a randomized, placebo-controlled, double-blind study2012
In 22 adults, acute oxazepam 30 mg reduced state anxiety and increased calmness under stress testing, whereas a medicinal kava dose (180 mg kavalactones) did not reduce anxiety versus placebo.
5.SupplementDEX Database: Anxiety — The Kava Anxiety Depression Spectrum Study (KADSS): a randomized, placebo-controlled crossover trial using an aqueous extract of Piper methysticum2009
In 60 adults, aqueous kava 250 mg kavalactones/day for 3 weeks reduced Hamilton Anxiety scores by ~10 points versus ~1 point with placebo (p<0.0001) with no hepatotoxicity signals.
22.SupplementDEX Database: Anxiety — Kava in generalized anxiety disorder: three placebo-controlled trials2006
Three pooled placebo-controlled kava trials (64 adults with GAD) found no significant benefit of kava over placebo for anxiety, though kava was well tolerated without hepatotoxicity.
6.SupplementDEX Database: Anxiety — Meta-analysis of the efficacy of the acetonic kava-kava extract WS1490 in patients with non-psychotic anxiety disorders2005
A meta-analysis of WS1490 kava extract trials found OR 3.3 for anxiety improvement in non-psychotic anxiety disorders, with HAMA scores ~6 points better than placebo.
7.SupplementDEX Database: Anxiety — An internet-based randomized, placebo-controlled trial of kava and valerian for anxiety and insomnia2005
An internet-based RCT (391 adults) found neither kava nor valerian reduced anxiety or insomnia scores more than placebo over 4 weeks.
8.SupplementDEX Database: Anxiety — Clinical efficacy of kava extract WS 1490 in sleep disturbances associated with anxiety disorders. Results of a multicenter, randomized, placebo-controlled, double-blind clinical trial2004
In 61 adults with sleep disturbance and anxiety, kava WS1490 200 mg/day for 4 weeks improved sleep quality and recuperative effect versus placebo (p=0.007 and p=0.018).
9.SupplementDEX Database: Anxiety — Kava treatment in patients with anxiety2004
In 50 adults with non-psychotic anxiety, kava WS1490 150 mg/day for 4 weeks reduced Hamilton Anxiety scores more than placebo with good tolerability.
18.SupplementDEX Database: Anxiety — Enhanced cognitive performance and cheerful mood by standardized extracts of Piper methysticum (Kava-kava)2004
In healthy adults, a single 300 mg kava dose increased state cheerfulness and improved visual attention and short-term memory tasks versus baseline without cognitive impairment.
10.SupplementDEX Database: Anxiety — Kava extract for treating anxiety2003
A Cochrane meta-analysis of 11 kava trials (645 participants) found kava reduced Hamilton Anxiety scores by 5 points versus placebo (p=0.01) with mild, infrequent adverse events over 1–24 weeks.
11.SupplementDEX Database: Anxiety — Kava-Kava extract LI 150 is as effective as Opipramol and Buspirone in Generalised Anxiety Disorder--an 8-week randomized, double-blind multi-centre clinical trial in 129 out-patients2003
In 127 outpatients with generalized anxiety disorder, kava LI150 400 mg/day for 8 weeks was as effective as buspirone or opipramol, with ~75% responders and ~60% remission in each group.
12.SupplementDEX Database: Anxiety — Treatment of anxiety, tension and restlessness states with Kava special extract WS 1490 in general practice: a randomized placebo-controlled double-blind multicenter trial2003
In 141 outpatients with neurotic anxiety, kava WS1490 150 mg/day for 4 weeks improved anxiety and well-being versus placebo, though effects were smaller than seen with 300 mg/day in prior trials.
26.SupplementDEX Database: Anxiety — Kava-Kava administration reduces anxiety in perimenopausal women2003
In perimenopausal women, kava 100–200 mg/day for 3 months reduced anxiety and climacteric symptoms more than calcium alone, with significant anxiety decline versus controls (P<0.009).
13.SupplementDEX Database: Anxiety — A placebo-controlled study of Kava kava in generalized anxiety disorder2002
In 37 adults with generalized anxiety disorder, 4 weeks of kava did not significantly outperform placebo overall, though post-hoc analyses suggested benefit in low-anxiety and placebo superiority in high-anxiety subgroups.
24.SupplementDEX Database: Anxiety — Effect of kava and valerian on human physiological and psychological responses to mental stress assessed under laboratory conditions2002
In 54 healthy adults, 7 days of kava or valerian reduced systolic blood pressure reactivity to mental stress versus baseline; valerian also lowered heart rate reactivity.
14.SupplementDEX Database: Anxiety — Efficacy of kava-kava in the treatment of non-psychotic anxiety, following pretreatment with benzodiazepines2001
In 40 adults tapering off benzodiazepines, kava WS1490 300 mg/day for 3 weeks reduced Hamilton Anxiety and improved well-being more than placebo (p=0.01 and p=0.002).
23.SupplementDEX Database: Anxiety — Kava and valerian in the treatment of stress-induced insomnia2001
In 24 adults with stress-induced insomnia, kava 120 mg/day for 6 weeks then valerian 600 mg/day for 6 weeks reduced stress and insomnia with vivid dreams as the commonest valerian side effect.
15.SupplementDEX Database: Anxiety — Efficacy of kava extract for treating anxiety: systematic review and meta-analysis2000
An early meta-analysis of 7 kava trials found kava superior to placebo for anxiety symptom reduction, supporting kava as a short-term anxiolytic alternative.
25.SupplementDEX Database: Anxiety — The correlation between cancer incidence and kava consumption2000
Ecological comparison across Pacific Island nations suggested higher traditional kava consumption correlates with lower age-standardized cancer incidence, though causality was not established.
16.SupplementDEX Database: Anxiety — Kava-kava extract WS 1490 versus placebo in anxiety disorders--a randomized placebo-controlled 25-week outpatient trial1997
In 101 outpatients with non-psychotic anxiety, kava WS1490 was superior to placebo on HAMA from week 8 through 25 weeks with good tolerability versus tricyclics or benzodiazepines.
17.SupplementDEX Database: Anxiety — Efficacy of a special Kava extract (Piper methysticum) in patients with states of anxiety, tension and excitedness of non-mental origin - A double-blind placebo-controlled study of four weeks treatment1996
In 58 adults with non-psychiatric anxiety, kava WS1490 300 mg/day for 4 weeks reduced HAMA scores from week 1 onward versus placebo with no drug-related adverse events.