Research
Kava
54 peer-reviewed studies curated from PubMed and Semantic Scholar.
Studies
Sorted by quality and recency
Global Perspectives on Kava: A Narrative Systematic Review of the Health Effects, Economic and Social Impacts and Policy Considerations.
This narrative systematic review examines global literature on kava, focusing on its health effects, economic and social impacts, and policy considerations. The review includes 197 records and highlights the unclear role of kava in liver toxicity and anxiety reduction, while emphasizing its social, cultural, and economic significance in Pacific Islander countries.
The effectiveness and safety of Kava Kava for treating anxiety symptoms: A systematic review and analysis of randomized clinical trials.
Systematic review and analysis of 11 randomized clinical trials on Kava Kava for anxiety treatment. Kava Kava was more effective than placebo in 3 of 7 trials, with a risk ratio of 1.50 favoring the intervention. Adverse events were similar to placebo, with no significant hepatotoxicity observed except in two studies.
Kava extract for treating anxiety.
Meta-analysis of 11 trials with 645 participants assessing kava extract for anxiety. Kava extract showed a significant reduction in anxiety symptoms compared to placebo, with mild and infrequent adverse events. Kava appears effective and relatively safe for short-term treatment.
One-Week Kava Dietary Supplementation Increases Both Urinary- and-Glucuronides of NNAL, a Lung Carcinogen Major Metabolite, among Smokers.
This study investigated the effects of one-week kava dietary supplementation on urinary excretion of NNAL, a major metabolite of the lung carcinogen NNK, among smokers. Kava increased both NNAL-N-glucuronidation and O-glucuronidation, suggesting enhanced detoxification of NNAL. The study also analyzed UGT2B10 SNPs, finding that genetic variations may influence the extent of kava's benefits.
Effect of kava (Piper methysticum) on peripheral gene expression among individuals with generalized anxiety disorder: A post hoc analysis of a randomized controlled trial.
Post hoc analysis of a double-blind randomized controlled trial assessing kava's effect on gene expression in individuals with generalized anxiety disorder. Kava decreased expression of GABRR2 and COMT genes, suggesting interaction with GABAergic and catecholaminergic systems. Results require external validation.
The protective effects of Kava (Piper Methysticum) constituents in cancers: A systematic review.
Systematic review summarizing evidence of anticancer effects of kava components, particularly flavokavain B and A, in various cancer models. Antiproliferative properties were demonstrated in 32 out of 39 papers, with increased expression of pro-apoptotic proteins and decreased expression of anti-apoptotic proteins.
Kava for Generalized Anxiety Disorder: A Review of Current Evidence.
Systematic review and meta-analysis of Kava for treating generalized anxiety disorder (GAD). Evidence from three placebo-controlled trials favored Kava with effect sizes between 0.59 and 0.99, but results were not statistically significant. Kava is considered safe and well-tolerated for short-term use.
Complementary and Alternative Medicine Treatments for Generalized Anxiety Disorder: Systematic Review and Meta-analysis of Randomized Controlled Trials.
Systematic review and meta-analysis of randomized controlled trials evaluating complementary and alternative medicine methods for generalized anxiety disorder. Kava Kava and Lavender extracts showed modest efficacy compared to placebo, but evidence is limited and requires further confirmation.
Kava for the treatment of generalised anxiety disorder (K-GAD): study protocol for a randomised controlled trial.
This is a phase III, multi-site, 18-week, randomised, double-blind, placebo-controlled study assessing the efficacy of an aqueous extract of noble kava cultivar in 210 participants with generalised anxiety disorder (GAD). The study aims to evaluate kava's effectiveness and safety as a treatment for GAD, with primary outcomes measured by the Hamilton Anxiety Rating Scale and secondary outcomes including affective disorder symptoms and quality of life.
Is driving under the influence of kava associated with motor vehicle crashes? A systematic review of the epidemiological literature.
Systematic review examining the association between kava use and motor vehicle crashes (MVCs), MVC-related injuries, or driving performance. No studies quantifying the effects of kava on MVCs were found. Experimental studies showed weak evidence of slowed reaction time and impaired visuo-motor performance when kava was consumed with alcohol.
Neurocognitive effects of kava (Piper methysticum): a systematic review.
Systematic review of ten human clinical trials assessing the effects of kava on cognition. Findings include improved visual attention and working memory in some studies, while others noted increased body sway and impaired visual attention under high cognitive demand. Overall, evidence suggests no significant negative effects on cognition.
Generalised anxiety disorder.
Systematic review examining the effectiveness and safety of various treatments for generalised anxiety disorder, including kava, antidepressants, antipsychotic drugs, applied relaxation, benzodiazepines, buspirone, cognitive behavioural therapy, hydroxyzine, and pregabalin.
An effect-size analysis of pharmacologic treatments for generalized anxiety disorder.
Meta-analysis of 21 double-blind placebo-controlled trials assessing pharmacologic treatments for generalized anxiety disorder (GAD). The study found that complementary/alternative medicine (CAM), including kava-kava and homeopathic preparations, had a negative effect size compared to placebo, indicating worse outcomes.
An internet-based randomized, placebo-controlled trial of kava and valerian for anxiety and insomnia.
Internet-based RCT of 391 participants testing kava for anxiety and valerian for insomnia. Neither kava nor valerian showed significant improvement over placebo in reducing anxiety or improving sleep quality.
Meta-analysis of the efficacy of the acetonic kava-kava extract WS1490 in patients with non-psychotic anxiety disorders.
Meta-analysis of six placebo-controlled, randomized trials assessing the efficacy of the kava extract WS1490 in patients with non-psychotic anxiety disorders. WS1490 showed a significant improvement in anxiety symptoms compared to placebo, with an effective success rate of OR=3.3. Kava was found to be more effective in females and younger patients.
Safety review of kava (Piper methysticum) by the Natural Standard Research Collaboration.
This systematic review discusses the proposed uses, dosing parameters, adverse effects, toxicology, interactions, and mechanism of action of kava. It highlights concerns regarding potential hepatotoxicity and recommends consolidating reports and continuing postmarket surveillance.
Kava extract for treating anxiety.
Systematic review of randomized controlled trials assessing the efficacy and safety of kava extract versus placebo for treating anxiety. Seven trials met the inclusion criteria, with results suggesting kava extract is superior to placebo and relatively safe. Meta-analysis showed a significant treatment effect in favor of kava extract.
Kava extract for treating anxiety.
Systematic review of randomized, double-blind trials assessing the efficacy and safety of kava extract for treating anxiety. The review found kava extract to be superior to placebo with mild, transient, and infrequent adverse events. Meta-analysis showed a significant treatment effect in favor of kava extract.
Efficacy of kava extract for treating anxiety: systematic review and meta-analysis.
Systematic review and meta-analysis assessing the efficacy of kava extract for treating anxiety. Seven trials reviewed, with meta-analysis of three trials showing kava extract significantly reduces anxiety scores compared to placebo.
Kavalactones support motivation to move during intensive training in males preparing for military special operations forces.
Placebo-controlled crossover study of kavalactones in 15 healthy males preparing for military special operations forces. Kavalactones supported motivation to expend energy during intensive training, with no significant effects on cortisol, sleep, or mood.
Neuroimaging Insights: Kava's () Effect on Dorsal Anterior Cingulate Cortex GABA in Generalized Anxiety Disorder.
This study investigated the effect of Kava on dorsal anterior cingulate cortex GABA levels in 37 adults with Generalized Anxiety Disorder. Participants received Kava or placebo for eight weeks. The Kava group showed a significant reduction in dACC GABA levels compared to placebo, suggesting an inhibitory effect independent of reported anxiety symptoms.
Kava drinking in traditional settings: Towards understanding effects on cognitive function.
RCT comparing cognitive functions of 20 control participants against 20 kava-drinking participants during and after a 6-hour kava session. No statistically significant differences in reaction and divided attention were found, despite observed slowing of movements and speech in kava drinkers.
Kava for generalised anxiety disorder: A 16-week double-blind, randomised, placebo-controlled study.
A 16-week double-blind, randomised, placebo-controlled study assessed the efficacy and safety of Kava in treating generalised anxiety disorder in 171 participants. The study found no significant difference in anxiety reduction between the Kava and placebo groups. Kava was well tolerated but associated with poorer memory and tremor/shakiness. Liver function test abnormalities were more frequent in the Kava group, but no cases of herb-induced hepatic injury were observed.
Kava for the treatment of generalized anxiety disorder RCT: analysis of adverse reactions, liver function, addiction, and sexual effects.
A 6-week double-blind RCT with 75 participants with generalized anxiety disorder, testing kava versus placebo. Kava showed no significant adverse reactions or liver function differences. It significantly increased female sexual drive and improved sexual function correlated with anxiety reduction.
Kava in the treatment of generalized anxiety disorder: a double-blind, randomized, placebo-controlled study.
A double-blind, randomized, placebo-controlled study of 75 participants with generalized anxiety disorder (GAD) assessing the effects of an aqueous extract of kava. The kava group showed a significant reduction in anxiety compared to placebo, with a moderate effect size. Specific GABA transporter polymorphisms were associated with the anxiolytic response to kava.
Kava Anxiety Depression Spectrum Study (KADSS): a mixed methods RCT using an aqueous extract of Piper methysticum.
The Kava Anxiety Depression Spectrum Study (KADSS) is a 3-week placebo-controlled, double-blind, cross-over trial involving 60 adults with elevated anxiety and varying levels of depressive symptoms. The study aims to assess the anxiolytic and thymoleptic efficacy of an aqueous extract of kava, as well as its safety and participants' experiences.
The Kava Anxiety Depression Spectrum Study (KADSS): a randomized, placebo-controlled crossover trial using an aqueous extract of Piper methysticum.
The Kava Anxiety Depression Spectrum Study was a 3-week placebo-controlled, double-blind crossover trial with 60 adults with elevated generalized anxiety. The aqueous extract of Kava significantly reduced anxiety and depression scores compared to placebo, with no serious adverse effects or clinical hepatotoxicity.
Kava in generalized anxiety disorder: three placebo-controlled trials.
Three randomized, double-blind, placebo-controlled trials evaluated the efficacy and safety of kava in generalized anxiety disorder. The pooled analysis of 64 participants found no significant effects for kava compared to placebo, with a significant effect in favor of placebo in participants with higher anxiety at baseline. No evidence of hepatotoxicity was found, and all treatments were well tolerated.
Herbal remedies for anxiety - a systematic review of controlled clinical trials.
Systematic review of controlled clinical trials on herbal remedies for anxiety. Piper methysticum (kava) and Bacopa monniera were studied, with kava showing anxiolytic effects in humans. The review highlights a lack of rigorous studies in this area.
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.
Multicenter, randomized, double-blind clinical trial of 61 patients with sleep disturbances associated with anxiety, comparing 200 mg kava extract WS 1490 to placebo over 4 weeks. Kava extract significantly improved sleep quality, recuperative effect after sleep, and anxiety scores, with good safety and tolerability.
Explanatory attributions of anxiety and recovery in a study of kava.
Post hoc analysis of two randomized, double-blinded, placebo-controlled trials of kava in 51 outpatients with generalized anxiety disorder (GAD). The study evaluated explanatory beliefs about GAD and treatment response, finding that beliefs about personality, stress, and cognitive patterns correlated positively with treatment response, while beliefs in energy imbalance or biologic abnormality correlated negatively.
Kava treatment in patients with anxiety.
RCT of 50 patients with non-psychotic anxiety treated with 150 mg kava extract WS 1490 per day for 4 weeks. The kava group showed a significant reduction in anxiety scores compared to placebo, with no drug-related adverse events.
Enhanced cognitive performance and cheerful mood by standardized extracts of Piper methysticum (Kava-kava).
Double-blind randomized placebo-controlled trial investigating the effects of Kava-kava on mood and cognitive performance in healthy volunteers. A single dose of Kava extract increased state cheerfulness and improved accuracy and speed in cognitive tasks, indicating enhanced visual attention and short-term memory retrieval.
Treatment of anxiety, tension and restlessness states with Kava special extract WS 1490 in general practice: a randomized placebo-controlled double-blind multicenter trial.
RCT investigating the efficacy and tolerability of 150 mg/d Kava special extract WS 1490 in 141 patients with neurotic anxiety. The WS 1490 group showed more pronounced decreases in anxiety scores compared to placebo, with significant improvements in general well-being. WS 1490 was well tolerated with minimal adverse effects.
Kava-Kava administration reduces anxiety in perimenopausal women.
A 3-month randomized prospective open study in perimenopausal women comparing calcium supplementation alone to calcium plus Kava-Kava. Kava-Kava significantly reduced anxiety, depression, and climacteric symptoms compared to controls.
Effect of kava and valerian on human physiological and psychological responses to mental stress assessed under laboratory conditions.
This study investigated the effects of kava and valerian on physiological and psychological responses to mental stress in 54 healthy volunteers. Participants took kava, valerian, or acted as controls for 7 days. Both kava and valerian groups showed a significant decrease in systolic BP responsivity and reported less pressure during the stress task, suggesting potential benefits in reducing physiological reactivity to stress.
Evaluation of combining kava extract with hormone replacement therapy in the treatment of postmenopausal anxiety.
RCT evaluating the efficacy of combining kava extract with hormone replacement therapy in treating menopausal anxiety. Significant reduction in HAMA score was observed, with greater improvement in groups taking kava extract compared to hormone therapy alone.
Does a medicinal dose of kava impair driving? A randomized, placebo-controlled, double-blind study.
RCT using a driving simulator to compare the effects of kava, oxazepam, and placebo on driving ability in 22 adults. Kava (180 mg of kavalactones) did not impair driving ability compared to placebo, while oxazepam showed impairing effects. Kava resulted in fewer lapses of concentration compared to oxazepam.
The acute effects of kava and oxazepam on anxiety, mood, neurocognition; and genetic correlates: a randomized, placebo-controlled, double-blind study.
RCT comparing the acute effects of kava, oxazepam, and placebo on anxiety, mood, and neurocognition in 22 moderately anxious adults. Kava showed no anxiolytic activity and no negative effects on cognition, while oxazepam reduced anxiety and alertness.
A placebo-controlled study of Kava kava in generalized anxiety disorder.
RCT assessing the efficacy and safety of Kava kava in treating generalized anxiety disorder in 37 adults. No significant differences were found in the principal analysis, but post-hoc analyses showed kava was superior in low anxiety cases on the SARA scale, while placebo was superior in high anxiety cases on the HADS and SARA scales. Both treatments were well tolerated.
Efficacy of kava-kava in the treatment of non-psychotic anxiety, following pretreatment with benzodiazepines.
A 5-week randomized, placebo-controlled, double-blind study investigated the efficacy of kava-kava extract WS1490 in treating non-psychotic anxiety, tension, and restlessness. WS1490 was superior to placebo in reducing anxiety symptoms as measured by the Hamilton Anxiety Scale and subjective well-being scale, with good tolerance and safety.
Kava and valerian in the treatment of stress-induced insomnia.
Pilot study of 24 patients with stress-induced insomnia treated with kava 120 mg daily for 6 weeks, followed by valerian 600 mg daily for another 6 weeks. Both compounds significantly relieved stress and insomnia with no significant differences between them. Common side effects included vivid dreams with valerian and dizziness with kava.
Effect of kava extract on vagal cardiac control in generalized anxiety disorder: preliminary findings.
This study examined the effect of kava extract on vagal cardiac control in patients with generalized anxiety disorder. Kava treatment improved baroreflex control of heart rate (BRC) compared to placebo, and the improvement in BRC was correlated with clinical improvement. Respiratory sinus arrhythmia (RSA) did not respond to treatment.
[Assessment of the association of Kava-Kava extract and hormone replacement therapy in the treatment of postmenopause anxiety].
RCT evaluating the efficacy of Kava-Kava extract combined with hormone replacement therapy (HRT) versus HRT alone in treating postmenopausal anxiety. Forty women in menopause were treated for 6 months. The combination of Kava-Kava and HRT showed a greater reduction in anxiety scores compared to HRT alone.
Kava-kava extract WS 1490 versus placebo in anxiety disorders--a randomized placebo-controlled 25-week outpatient trial.
A 25-week multicenter randomized placebo-controlled double-blind trial with 101 outpatients suffering from anxiety disorders compared WS 1490, a kava-kava extract, to placebo. WS 1490 showed significant superiority in reducing anxiety as measured by the Hamilton Anxiety Scale and other secondary outcome variables, supporting its use as a treatment alternative to tricyclic antidepressants and benzodiazepines.
Pharmacopsychological effects of oxazepam and kava-extract in a visual search paradigm assessed with event-related potentials.
The study investigated the effects of oxazepam and a standardized extract of kava-roots (WS1490) on reaction time and event-related potentials (ERPs) in a visual search paradigm using a double-blind design in young, healthy males. WS 1490 was associated with changes in ERP components, including a greater posterior N1, posterior contralateral N2, and occipital P3.
[Effect of a special kava extract in patients with anxiety-, tension-, and excitation states of non-psychotic genesis. Double blind study with placebos over 4 weeks].
A randomized, placebo-controlled double-blind study with 58 patients with anxiety syndrome treated for 4 weeks with kava extract WS 1490 or placebo. The kava group showed a significant reduction in anxiety symptoms as measured by the Hamilton-Anxiety-Scale, with no adverse experiences reported.
[Effect of Kava-Special Extract WS 1490 combined with ethyl alcohol on safety-relevant performance parameters].
A placebo-controlled randomized double-blind study tested the effects of Kava-special extract WS 1490 combined with ethyl alcohol on safety-related performance in 20 healthy volunteers. The study found no negative multiplicative effects, and a notable improvement in concentration tests for the WS 1490 group on the 4th day of treatment.
Effects of oxazepam and an extract of kava roots (Piper methysticum) on event-related potentials in a word recognition task.
Double-blind crossover study with 12 healthy volunteers assessing the effects of oxazepam and kava extract on recognition memory task performance and event-related potentials. Kava showed a slightly increased recognition rate and a larger ERP difference between old and new words compared to oxazepam.
[Psychosomatic dysfunctions in the female climacteric. Clinical effectiveness and tolerance of Kava Extract WS 1490].
RCT of 40 patients with climacteric-related symptoms treated with kava extract WS 1490 or placebo for 8 weeks. Kava extract significantly improved anxiety symptoms, depressive mood, subjective well-being, and climacteric symptomatology with good tolerance.
Kava-induced dermopathy: a niacin deficiency?
RCT involving 29 heavy kava drinkers in the Tonga Islands to investigate the cause of a pellagroid dermopathy associated with kava consumption. Participants were randomized to receive either 100 mg oral nicotinamide or placebo daily for three weeks. Clinical improvement was observed in both groups, suggesting that niacin deficiency is not responsible for the rash, which resembles acquired ichthyosis.
Kava Withdrawal Treated With Phenobarbital-A Case Report and Literature Review.
Case report of a man experiencing acute kava withdrawal with hyperactive delirium, treated with phenobarbital. The paper includes a systematic review of kava withdrawal literature, finding limited reports and no prior publications on treatment.
Cytochrome P450 enzyme mediated herbal drug interactions (Part 2)
This review article discusses herbal drug interactions mediated by cytochrome P450 enzymes, focusing on several herbs including kava. It highlights that kava may significantly inhibit CYP1A2 and CYP2E1, suggesting caution when taken with drugs metabolized by these enzymes. The article emphasizes the need for further clinical trials to verify these interactions.
Studies on the efficacy of unconventional therapies. Problems and designs.
The paper discusses challenges and designs for studying unconventional therapies, including dietary, phytotherapy, acupuncture, and homeopathy. It describes a study investigating the herbal remedy Kava-Kava for anxiety, tension, and restlessness, and compares designs for dietary studies in rheumatoid arthritis patients.