Treatment of anxiety, tension and restlessness states with Kava special extract WS 1490 in general practice: a randomized placebo-controlled double-blind multicenter trial

Kava Withdrawal Treated with Phenobarbital-A Case Report and Literature Review

ABSTRACT

Kava consumption is a traditional practice in Polynesian and Micronesian cultures. It has recently gained popularity in the United States for therapeutic and recreational use. We report the following case. A man presented to the emergency department after a fall while intoxicated on kava. He was medically admitted for altered mental status, facial and clavicle fractures, and hyponatremia. Psychiatry was consulted for management of delirium. On interview, he reported consuming escalating amounts of kava for weeks despite attempts to stop. He was diagnosed with acute kava withdrawal with hyperactive delirium, treated with phenobarbital load (860 mg) and taper (390 mg). Continuous dexmedetomidine drip to hospital day 3 treated sympathetic activation and breakthrough agitation. By day 4, his delirium resolved and remained in remission until discharge. We performed a systematic review for reports of kava withdrawal, returning 9 studies. Eight assessed withdrawal symptoms after cessation of a low controlled dose of kava extract with no symptoms noted. One reported a case series of heavy kava users with seizure-like events. No publications discussed treatment of kava withdrawal. To our knowledge, this is the first publication to describe kava withdrawal syndrome and its effective treatment with phenobarbital.

Herbal Approaches in the Management of Mental Depression

BACKGROUND

Human's existence has become more stressful these days, most likely for the sake of improving one's lifestyle and fulfilling one's aspirations and needs. Depression is the most frequent neurological disorder, which affects millions of individuals worldwide. In clinical research, depression is the second most frequent chronic disease. A variety of herbal medications thought to have antidepressant-like effects have been reported in ancient pharmacopoeias from around the world. These provide several prospective chemicals that could be developed into modern mental medications while also causing no noticeable negative effects.

OBJECTIVE

The review is written to provide herbal treatment and comprehensive information about depression.

METHODS

Plants and plant formulations that were found effective in the treatment of depression are thoroughly reviewed. The antidepressant efficacies of medicinal plants, as well as their dosages, are investigated using experimental models. The review article contains 140 plants possessing antidepressant properties, 11 commercial formulations, and 25 active/isolated ingredients, as well as their chemical structure, which have been thoroughly reviewed with antidepressant activity after studying 283 references.

RESULTS

Literature revealed that a variety of medicinal plants are effective for the treatment of depression such as Hypericum perforatum, Catha edulis, Tinospora cordifolia, Curcuma longa, Ferula foetida, Rhodio larosea, Glycyrrhiza glabra, Crocus sativus, Ocimumba silicum and Embelica officinalis.

CONCLUSION

Potential compounds isolated from medicinal plants for the treatment of depressive disorders need to be established and herbal plant research could aid in this endeavour.

Clinical pharmacokinetics of kavalactones after oral dosing of standardized kava extract in healthy volunteers

ETHNOPHARMACOLOGICAL RELEVANCE

Piper methysticum G. Forst. (Piperaceae), commonly known as kava, has been used as a traditional beverage for centuries for its relaxing properties. Kavalactones are considered to be the major constituents responsible for kava's beneficial effects. Despite the extensive use of kava, clinical pharmacokinetic data is not available in the literature; therefore, the findings of this study will be critical for the dosage calculations for future clinical evaluation of kava.

AIM OF THE STUDY

The aim of the current study is to examine the clinical pharmacokinetics of six major kavalactones following oral dosing of flavokavain A/B-free standardized kava extract capsules in healthy volunteers using two dosage regimens.

MATERIALS AND METHODS

A sensitive, reliable, and specific ultra-high pressure liquid chromatography-mass spectrometry (UPLC-MS/MS) method was developed and validated for the simultaneous quantification of six major kavalactones (kavain, dihydrokavain, methysticin, dihydromethysticin, yangonin, and desmethoxyyangonin) and two flavokavains (A and B) in human plasma. Pharmacokinetic profiles were assessed in ten healthy volunteers after oral doses of standardized kava product, and plasma samples were analyzed for six kavalactones and two flavokavains using the validated UPLC-MS/MS method. Concentration-time data was subjected to pharmacokinetic analysis.

RESULTS

The systemic exposure of the kavalactones was found to be in the following order: dihydrokavain > dihydromethysticin > kavain > methysticin > yangonin. Desmethoxyyangonin was quantifiable only at a couple of time points, while flavokavain A and flavokavain B were not present in any of the plasma samples. Fast absorption of five kavalactones was observed with time to reach the maximum plasma concentration of 1-3 h. A dose proportionality in pharmacokinetics was established from 75 to 225 mg of kavalactone doses. In the multiple-dose study, a significant reduction in the extent of absorption of kavalactones with food was observed.

CONCLUSION

Single and multiple-dose clinical pharmacokinetic studies for kava were performed in healthy volunteers, and higher exposure to the kavalactones was observed after single-dosing (225 mg), while a longer duration of exposure was observed after three times a day (3 x 75 mg) dosing.

Health policy versus kava (Piper methysticum): Anxiolytic efficacy may be instrumental in restoring the reputation of a major South Pacific crop

ETHNOPHARMACOLOGICAL RELEVANCE

Kava (Piper methysticum G. Forst. f.) is by far the most important plant used in the islands of Melanesia, Polynesia and Micronesia for its relaxing effects. Kava drinking is a pillar of South Pacific societies and is also the foundation of their economies. Preparations of kava extract as herbal medicinal drugs were banned in Germany in 2002 and again in 2019, with dramatic consequences for the South Pacific economies. In 2002, the major regulatory argument for the ban of kava was safety issues. In 2019, the assessment report of the European Medicines Agency's Herbal Medicinal Product Committee (HMPC) justified a negative benefit-to-risk ratio by a supposed lack of efficacy of ethanolic extracts for an indication of which kava extract preparations never had an approval. In this HMPC report the efficacy in the approved indications 'nervous anxiety, tension and restlessness' was attributed to the extract branded as 'WS 1490', which was assumed to have been prepared with acetone as an extraction solvent. In addition to this change of indication and the attribution of efficacy to acetone kava extract alone, the German health authorities and the HMPC still refuse to discuss quality issues as a likely factor impacting drug safety. The first case reports of liver toxicity were observed with an acetone extract in a timely relationship with the introduction of 'two-day kava' instead of 'noble kava' as used in ethanolic kava extracts.

AIM OF THE STUDY

The correlation between clinical benefits and the type of extract preparation was examined.

METHODS

In order to identify the types of kava material and extracts used in clinical trials, the respective publications were compared with regulatory databases and protocols of a German regulatory advisory board.

RESULTS AND CONCLUSIONS

The comparison reveals inconsistencies in the regulatory decisions. In all studies with WS 1490, the evidence points to the use of an ethanolic extract. The efficacy of kava extract for the approved indication was clearly demonstrated. The HMPC report and the recent renewed German regulatory ban of kava therefore require major revision, which should include the impact of the use of "two-day kava" on drug safety. Such a revision could contribute to restoring the reputation of "noble kava" on the international markets.

Risk Associated with the Use of Selected Ingredients in Food Supplements

This review focuses on four new product categories of food supplements: pre-workout, fat burner/thermogenic, brain/cognitive booster, and hormone/testosterone booster. Many food supplements have been shown to be contaminated with unauthorized substances. In some cases, the ingredients in the new categories of dietary supplements were medicinal products or new synthetic compounds added without performing clinical trials. Some of the new ingredients in dietary supplements are plant materials that are registered in the pharmacopoeia as herbal medicines. In other cases, dietary supplements may contain plant materials that have no history of human use and are often used as materials to 'camouflage' stimulants. In the European Union, new ingredients of dietary supplements, according to European Food Safety Authority or unauthorized novel food. Furthermore, selected ingredients in dietary supplements may be prohibited in sports and are recognized as doping agents by World Anti-Doping Agency.

Pharmacology of Herbal Sexual Enhancers: A Review of Psychiatric and Neurological Adverse Effects

Sexual enhancers increase sexual potency, sexual pleasure, or libido. Substances increasing libido alter the concentrations of specific neurotransmitters or sex hormones in the central nervous system. Interestingly, the same pathways are involved in the mechanisms underlying many psychiatric and neurological disorders, and adverse reactions associated with the use of aphrodisiacs are strongly expected. However, sexual enhancers of plant origin have gained popularity over recent years, as natural substances are often regarded as a safer alternative to modern medications and are easily acquired without prescription. We reviewed the psychiatric and neurological adverse effects associated with the consumption of herbal aphrodisiacs Areca catechu L., Argemone Mexicana L., Citrus aurantium L., Eurycoma longifolia Jack., Lepidium meyenii Walp., Mitragyna speciosa Korth., Panax ginseng C. A. Mey, Panax quinquefolius L., Pausinystalia johimbe (K. Schum.) Pierre ex Beille, Piper methysticum G. Forst., Ptychopetalum olacoides Benth., Sceletium tortuosum (L.) N. E. Brown, Turnera diffusa Willd. ex. Schult., Voacanga africana Stapf ex Scott-Elliot, and Withania somnifera (L.) Dunal. A literature search was conducted on the PubMed, Scopus, and Web of Science databases with the aim of identifying all the relevant articles published on the issue up to June 2020. Most of the selected sexual enhancers appeared to be safe at therapeutic doses, although mild to severe adverse effects may occur in cases of overdosing or self-medication with unstandardized products. Drug interactions are more concerning, considering that herbal aphrodisiacs are likely used together with other plant extracts and/or pharmaceuticals. However, few data are available on the side effects of several plants included in this review, and more clinical studies with controlled administrations should be conducted to address this issue.

Current Research on Complementary and Alternative Medicine (CAM) in the Treatment of Anxiety Disorders: An Evidence-Based Review

Complementary and alternative medicine (CAM) encompasses a wide range of different nonmainstream therapies that have been increasingly used for treatment or adjunctive treatment of various ailments with anxiety/anxiety disorders being one of the commonly CAM (self)-medicated conditions. Thousands of published papers refer to use of CAM in various psychiatric disorders or in healthy or medically ill patients with mood or anxiety difficulties. In this chapter we focus specifically on clinically diagnosed (in line with the standard criteria) anxiety disorders and overview evidence of efficacy/safety of a range of CAM modalities: biologically based therapies (typically herbal preparations and less so nutraceuticals); manipulative and body-based therapies (acupuncture, aerobic exercise, massage, therapeutic touch, repetitive transcranial magnetic stimulation, balneotherapy, and others); mind-body therapies (yoga, Morita therapy, Tai Chi, reiki, Chinese cognitive therapy, religious and spiritual interventions, relaxation, mediation, and mindfulness-based interventions); and alternative medical systems (Ayurveda, homeopathy). We focus exclusively on randomized controlled trials and attempt to evaluate the existing body of evidence in the same manner that is applied to mainstream treatments.

Novel pharmacological targets in drug development for the treatment of anxiety and anxiety-related disorders

Current medication for anxiety disorders is suboptimal in terms of efficiency and tolerability, highlighting the need for improved drug treatments. In this review an overview of drugs being studied in different phases of clinical trials for their potential in the treatment of fear-, anxiety- and trauma-related disorders is presented. One strategy followed in drug development is refining and improving compounds interacting with existing anxiolytic drug targets, such as serotonergic and prototypical GABAergic benzodiazepines. A more innovative approach involves the search for compounds with novel mechanisms of anxiolytic action using the growing knowledge base concerning the relevant neurocircuitries and neurobiological mechanisms underlying pathological fear and anxiety. The target systems evaluated in clinical trials include glutamate, endocannabinoid and neuropeptide systems, as well as ion channels and targets derived from phytochemicals. Examples of promising novel candidates currently in clinical development for generalised anxiety disorder, social anxiety disorder, panic disorder, obsessive compulsive disorder or post-traumatic stress disorder include ketamine, riluzole, xenon with one common pharmacological action of modulation of glutamatergic neurotransmission, as well as the neurosteroid aloradine. Finally, compounds such as D-cycloserine, MDMA, L-DOPA and cannabinoids have shown efficacy in enhancing fear-extinction learning in humans. They are thus investigated in clinical trials as an augmentative strategy for speeding up and enhancing the long-term effectiveness of exposure-based psychotherapy, which could render chronic anxiolytic drug treatment dispensable for many patients. These efforts are indicative of a rekindled interest and renewed optimism in the anxiety drug discovery field, after decades of relative stagnation.

Chemical and in vitro toxicity analysis of a supercritical fluid extract of Kava kava (Piper methysticum)

ETHNOPHARMACOLOGICAL RELEVANCE

Kava and kava extracts have shown great potential as a way to minimize anxiety-associated symptoms and to help alleviate pain. Hepatoxicity has been associated with the consumption of kava products. The chemical compounds, kavalactones (KL) and flavokavains (FK) have been implicated in kava's psychotropic and possible hepatotoxic properties.

AIM OF THE STUDY

To investigate the kavalactone and flavokavain content and in vitro toxicity of KAVOA™, a supercritical carbon dioxide extraction (SFE) of kava.

MATERIALS AND METHODS

Kavalactone and flavokavain content of SFE kava and noble kava root were determined following extraction in acetone, cell culture media, and water using ultra high-performance liquid chromatography (UHPLC). Using water extractions of the kava products, the cell viability and toxicity on the human hepatocellular carcinoma cell line (HepG2) were determined using luminescent and fluorescent assays, respectively. The half maximal inhibitory concentration (IC₅₀) of the SFE kava and noble kava root, extracted in cell culture media, were determined utilizing a luminescent cell viability assay.

RESULTS

Quantification of the KAVOA™, a SFE extract of kava and kava root showed similar profiles of kavalactone and flavokavain content. Water extracted SFE and root kava did not show a negative impact on cell viability and toxicity when compared to the vehicle control treated cells. IC₅₀ values were determined for the SFE kava and kava root extracted in cell culture media in respect to cell viability, 78.63 and 47.65 µg/mL, respectively.

CONCLUSIONS

KAVOA™, a supercritical carbon dioxide extract of kava displays a similar kavalactone profile to a noble variety of kava. In relation to total kavalactone content, KAVOA™ also has a lower content of the cytotoxic compound FKB. Aqueous extractions of KAVOA™ and noble kava root had no significant negative impact on cell viability and toxicity on HepG2 cells when compared to vehicle controlled treated cells. Results indicate KAVOA™ demonstrates a similar in vitro safety profile to that of noble kava root when experiments are normalized to kavalactone content.

The effectiveness and safety of Kava Kava for treating anxiety symptoms: A systematic review and analysis of randomized clinical trials

BACKGROUND

To determine if Kava Kava is an effective treatment for combating symptoms of anxiety despite warnings of hepatotoxicity from the Centers for Disease Control and Prevention (CDC).

METHODS

Databases PubMed, CINAHL, and PsycINFO were utilized to obtain clinical trials on Kava Kava and its effects on anxiety. A total of 11 articles met inclusion/exclusion criteria: 2 for Kava Kava vs. another anti-anxiety medication, 2 detailing additional adverse events, and 7 for Kava Kava vs. placebo. Mantel-Haenszel fixed-effects model was used to analyze the data, with responder rates being pooled to compute weighted risk ratios.

RESULTS

Kava Kava was shown to be more effective than placebo in 3 of the 7 trials. A final risk ratio of 1.50 (95% CI: 1.12, 2.01) from responder rates was calculated in favor of the intervention from 5 clinical trials (n = 330). Adverse events were shown to be the same as placebo (P = 0.574), and laboratory values analyzing hepatotoxicity were no different when compared to baseline except in two studies.

CONCLUSIONS

Kava Kava appears to be a short-term treatment for anxiety, but not a replacement for prolonged anti-anxiety use. Although not witnessed in this review, liver toxicity is especially possible if taken longer than 8 weeks.

The Pharmacology, Pharmacokinetics, Efficacy, and Adverse Events Associated With Kava

Kava is a plant with numerous kavapyrones that can induce pharmacologic effects and drug interactions through the cytochrome P450 and P-glycoprotein systems. Kava is used recreationally and for the treatment of anxiety. Clinical trials verify anxiolytic effects in excess of placebo, but the effects are not seen immediately and the optimal dose and dosing schedule needs to be determined. Clinical trials usually lasting for 4 weeks found generally good tolerability and safety; however, dermatologic, hepatologic, and cognitive adverse effects may occur. Some of these adverse effects are known to occur from the kavapyrones themselves, while others can be caused or exacerbated by use of substandard kava products. There is tremendous variability in the constitution of a kava product based on the parts of the plant that are being extracted and the extraction method. The most commonly studied extract for the treatment of anxiety is the acetone extract.

Kava for Generalized Anxiety Disorder: A Review of Current Evidence

BACKGROUND

Generalized anxiety disorder (GAD) is a chronic and debilitating condition characterized by persistent and overpowering anxiety. Treatment of GAD with antidepressants and benzodiazepines is only moderately effective and not free from side effects. Kava (Piper methysticum) has been explored as a potential phytotherapeutic option for GAD.

OBJECTIVES

To perform a systematic review and meta-analysis of the available evidence on Kava as a treatment for GAD.

METHODS

Systematic search of English-language publications from major databases for clinical trials reporting the effects of Kava for the treatment of GAD.

RESULTS

Twelve articles were included in this review. Evidence supporting Kava as an effective treatment for GAD was found in two placebo-controlled trials and a reference-controlled trial. One negative trial demonstrated that Kava was not more effective than placebo. Meta-analyses of the results of three placebo-controlled trials (n = 130) favored Kava for GAD treatment with effect sizes between 0.59 and 0.99 (standard mean difference) without reaching statistical significance. Kava is an appealing treatment option to GAD patients who are more attune to natural remedies or lifestyle approaches to reduce stress. Positive patient experiences and improvement of vagal cardiac control due to Kava treatment were also reported in the literature. Kava is safe and well tolerated for short-term (4-8 weeks) therapeutic use at a dosage of 120-280 mg per day of Kavalactones, regardless of dosage schedule.

CONCLUSIONS

Current evidence, although promising, is insufficient to confirm the effect of Kava for GAD treatment beyond placebo. New evidence is expected from a large, multisite ongoing trial.

Herbal medicine for depression and anxiety: A systematic review with assessment of potential psycho-oncologic relevance

Anxiety and depression are prevalent among cancer patients, with significant negative impact. Many patients prefer herbs for symptom relief to conventional medications which have limited efficacy/side effects. We identified single-herb medicines that may warrant further study in cancer patients. Our search included PubMed, Allied and Complementary Medicine, Embase, and Cochrane databases, selecting only single-herb randomized controlled trials between 1996 and 2016 in any population for data extraction, excluding herbs with known potential for interactions with cancer treatments. One hundred articles involving 38 botanicals met our criteria. Among herbs most studied (≥6 randomized controlled trials each), lavender, passionflower, and saffron produced benefits comparable to standard anxiolytics and antidepressants. Black cohosh, chamomile, and chasteberry are also promising. Anxiety or depressive symptoms were measured in all studies, but not always as primary endpoints. Overall, 45% of studies reported positive findings with fewer adverse effects compared with conventional medications. Based on available data, black cohosh, chamomile, chasteberry, lavender, passionflower, and saffron appear useful in mitigating anxiety or depression with favorable risk-benefit profiles compared to standard treatments. These may benefit cancer patients by minimizing medication load and accompanying side effects. However, well-designed larger clinical trials are needed before these herbs can be recommended and to further assess their psycho-oncologic relevance.

A Combination of Essential Fatty Acids, Panax Ginseng Extract, and Green Tea Catechins Modifies Brain fMRI Signals in Healthy Older Adults

OBJECTIVES

To assess the effects of a combination of omega 3 essential fatty acids, green tea catechins, and ginsenosides on cognition and brain functioning in healthy older adults.

DESIGN

Double-blind, placebo-controlled, crossover design randomized controlled trial with 26-day intervention phases and a 30-day washout period.

SETTING

The Institute for Dementia Research and Prevention at the Pennington Biomedical Research Center.

PARTICIPANTS

Ten independently-living, cognitively-healthy older adults (mean age: 67.3 + 2.01 years).

INTERVENTION

Daily consumption of an investigational product (trade name "Cerbella TM") consisting of an emulsified liquid combination of standardized fish oil, panax ginseng extract, and green tea catechins in a flavored base of lecithin phospholipids optimized to maximize bioavailability of the active ingredients.

MEASUREMENTS

Before and after supplementation with the investigational product or placebo, participants completed cognitive tests including the Mini Mental State Exam (MMSE), Stroop test, Digit Symbol Substitution Test (DSST), and Immediate and Delayed Recall tests, as well as functional magnetic resonance imaging (fMRI) during a standard cognitive task switching paradigm.

RESULTS

Performance on the MMSE, Stroop test, and DSST increased significantly over one month of supplementation with the investigational product (one-sample t tests, p<.05) although differences between these changes and corresponding changes during supplementation with placebo were not significant (two-sample t tests, p>.05). During supplementation with the investigational product, brain activation during task performance increased significantly more than during supplementation with placebo in brain regions known to be activated by this task (anterior and posterior cingulate cortex). Functional connectivity during task execution between task regions (middle frontal gyrus and anterior cingulate cortex) increased significantly during supplementation with the investigational product, relative to placebo. Functional connectivity during rest between task regions (precentral gyrus and middle frontal gyrus) and default mode network regions (medial frontal gyrus and precuneus) decreased during supplementation with the investigational product relative to placebo, suggesting greater segregation of task and rest related brain activity.

CONCLUSION

One-month supplementation with a combination of omega 3 essential fatty acids, green tea catechins, and ginsenosides was associated with suggestive changes in cognitive functioning as well as modification of brain activation and brain functional connectivity in cognitively healthy older adults.

Contemporary Pacific and Western perspectives on `awa (Piper methysticum) toxicology

In 2010, a National Science Foundation project in Hawai`i assembled a collaboration of Pacific indigenous scientists, Hawaiian cultural practitioners and scientists trained in Western pharmacology. The objective of the collaborative project was to study Kava, a culturally significant Pacific beverage, and to address and ultimately transcend, long-standing barriers to communication and collaboration between these groups. Kava is a product of the `awa plant (Piper methysticum) that has been used ceremonially and medicinally throughout the history of Pacific Island cultures, and is now in widespread recreational and nutraceutical use in the US. This project, culminating in 2015, has enriched the participants, led to published work that integrates cultural and Western pharmacologic perspectives and established a paradigm for collaboration. This review paper integrates cultural and Western perspectives on efficacy, toxicity and the future cultural and commercial significance of `awa in the Pacific. Here we present a detailed review of traditional and non-traditional kava usage, medicinal efficacy and potential toxicological concerns. Recent mechanistic data on physiological action and potential pathological reactions are evaluated and interpreted.

[Medicinal plants for the treatment of generalized anxiety disorder: a review of controlled clinical studies]

OBJECTIVE

This work aimed to identify controlled trials, which evaluated effectiveness of herbal medicines in subjects suffering generalized anxiety disorder.

METHOD

Controlled studies (randomized, comparative with placebo and/or standard drug, double-blind) were sought through electronic and hand-searches. The word strategy used "plant OR phytomed* OR extract OR herbal OR medicinal (OR specific name plants)" e "anxie* OR anxioly* OR tranquil* OR GAD", limited to "human OR clinical trial OR randomized controlled trial OR meta-analysis OR review". The search was restricted to English language.

RESULTS

Piper methysticum presented an unequivocal anxiolytic effect, but most studies also included patients with other anxiety disorders (e.g. phobias). Isolated studies with Ginkgo biloba, Galphimia glauca, Matricaria recutita, Passiflora incarnata and Valeriana officinalis showed a potential use for anxious diseases. Despite this low number of studies, Ginkgo biloba and Matricaria recutita showed an effect size (Cohen's d=0.47 to 0.87) similar or higher to standard anxiolytics drugs (benzodiazepines, buspirone and antidepressants-0.17 to 0.38). No additional study with other plants was found.

CONCLUSION

Despite the therapeutic potential of medicinal plants in generalized anxiety disorder, very few controlled trials assessing herbal medicines in generalized anxiety disorder were found. Additionally, these studies present serious flaw design.

Kava: a comprehensive review of efficacy, safety, and psychopharmacology

OVERVIEW

Kava (Piper methysticum) is a South Pacific psychotropic plant medicine that has anxiolytic activity. This effect is achieved from modulation of GABA activity via alteration of lipid membrane structure and sodium channel function, monoamine oxidase B inhibition, and noradrenaline and dopamine re-uptake inhibition. Kava is available over the counter in jurisdictions such as the USA, Australia and New Zealand. Due to this, a review of efficacy, safety and clinical recommendations is advised.

OBJECTIVE

To conduct a comprehensive review of kava, in respect to efficacy, psychopharmacology, and safety, and to provide clinical recommendations for use in psychiatry to treat generalized anxiety disorder (GAD).

METHODS

A review was conducted using the electronic databases MEDLINE, CINAHL, PsycINFO and the Cochrane Library during mid 2010 of search terms relating to kava and GAD. A subsequent forward search was conducted of key papers using Web of Science cited reference search.

RESULTS

The current weight of evidence supports the use of kava in treatment of anxiety with a significant result occurring in four out of six studies reviewed (mean Cohen's d = 1.1). Safety issues should however be considered. Use of traditional water soluble extracts of the rhizome (root) of appropriate kava cultivars is advised, in addition to avoidance of use with alcohol and caution with other psychotropic medications. Avoidance of high doses if driving or operating heavy machinery should be mandatory. For regular users routine liver function tests are advised.

CONCLUSIONS

While current evidence supports kava for generalized anxiety, more studies are required to assess comparative efficacy and safety (on the liver, cognition, driving, and sexual effects) versus established pharmaceutical comparators.

Nutritional and herbal supplements for anxiety and anxiety-related disorders: systematic review

BACKGROUND

Over the past several decades, complementary and alternative medications have increasingly become a part of everyday treatment. With the rising cost of prescription medications and their production of unwanted side effects, patients are exploring herbal and other natural remedies for the management and treatment of psychological conditions. Psychological disorders are one of the most frequent conditions seen by clinicians, and often require a long-term regimen of prescription medications. Approximately 6.8 million Americans suffer from generalized anxiety disorder. Many also suffer from the spectrum of behavioural and physical side effects that often accompany its treatment. It is not surprising that there is universal interest in finding effective natural anxiolytic (anti-anxiety) treatments with a lower risk of adverse effects or withdrawal.

METHODS

An electronic and manual search was performed through MEDLINE/PubMed and EBSCO. Articles were not discriminated by date of publication. Available clinical studies published in English that used human participants and examined the anxiolytic potential of dietary and herbal supplements were included. Data were extracted and compiled into tables that included the study design, sample population, intervention, control, length of treatment, outcomes, direction of evidence, and reported adverse events.

RESULTS

A total of 24 studies that investigated five different CAM monotherapies and eight different combination treatments and involved 2619 participants met the inclusion criteria and were analyzed. There were 21 randomized controlled trials and three open-label, uncontrolled observational studies. Most studies involved patients who had been diagnosed with either an anxiety disorder or depression (n = 1786). However, eight studies used healthy volunteers (n = 877) who had normal levels of anxiety, were undergoing surgery, tested at the upper limit of the normal range of a trait anxiety scale, had adverse premenstrual symptoms or were peri-menopausal, reported anxiety and insomnia, or had one month or more of elevated generalized anxiety. Heterogeneity and the small number of studies for each supplement or combination therapy prevented a formal meta-analysis. Of the randomized controlled trials reviewed, 71% (15 out of 21) showed a positive direction of evidence. Any reported side effects were mild to moderate.

CONCLUSIONS

Based on the available evidence, it appears that nutritional and herbal supplementation is an effective method for treating anxiety and anxiety-related conditions without the risk of serious side effects. There is the possibility that any positive effects seen could be due to a placebo effect, which may have a significant psychological impact on participants with mental disorders. However, based on this systematic review, strong evidence exists for the use of herbal supplements containing extracts of passionflower or kava and combinations of L-lysine and L-arginine as treatments for anxiety symptoms and disorders. Magnesium-containing supplements and other herbal combinations may hold promise, but more research is needed before these products can be recommended to patients. St. John's wort monotherapy has insufficient evidence for use as an effective anxiolytic treatment.

Complementary medicine for psychiatric disorders in children and adolescents

PURPOSE OF REVIEW

To examine recent empirical studies of herbal and dietary treatments for psychiatric disorders in children and adolescents.

RECENT FINDINGS

Very few quality studies into the use of omega-3 fatty acids, St John's wort, dietary manipulations, kava, gingko and lemon balm in managing psychiatric disorders have been conducted in children and adolescents.

SUMMARY

A number of herbal treatments show promise, but much more empirical research is required to establish their efficacy in the paediatric population.

Botanical and dietary supplements for mood and anxiety in menopausal women

OBJECTIVE

This paper reviews the commonly used botanicals for treatment of mood and anxiety disorders in perimenopausal and postmenopausal women and presents information on their safety and efficacy.

DESIGN

The MEDLINE and EMBASE databases were searched for clinical trials related to the use of botanicals for depression, anxiety, and mood disturbances. Papers were excluded if they were in a language other than English, did not include midlife women as study participants, or did not report on changes in mood, depression, or anxiety.

RESULTS

Five of seven trials of St. John's wort for mild to moderate depression showed a significant improvement. The one randomized, controlled trial of ginseng in postmenopausal women reported improvements in mood and anxiety. All three randomized, controlled trials of ginkgo found no effect on depression. In four of eight controlled trials, kava significantly reduced anxiety. Black cohosh significantly reduced depression and anxiety in all studies reviewed.

CONCLUSIONS

St. John's wort and black cohosh appear to be the most useful in alleviating mood and anxiety changes during menopause. Ginseng may be effective, but more research needs to be done. Kava holds promise for decreasing anxiety in peri- and postmenopausal women; however, women should be careful in the amount and duration of use. Finally, ginkgo and valerian do not appear to be useful in reducing depression or anxiety in this population.

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. The widespread concern regarding the potential hepatotoxicity of kava is discussed. A recommendation is made to consolidate and analyse available reports and to continue postmarket surveillance in an international repository to prevent duplicates and promote collection of thorough details at the time of each report so that any association with kava is clearly defined.

Kava extract for treating anxiety

BACKGROUND

Constraints on resources and time often render treatments for anxiety such as psychological interventions impracticable, while synthetic anxiolytic drugs are effective, but are often burdened with adverse events. Options which are effective and safe would be of considerable interest and a welcome addition to the therapeutic repertoire.

OBJECTIVES

To assess the effectiveness and safety as reported in rigorous clinical trials of kava extract compared with placebo for treating anxiety.

SEARCH STRATEGY

All publications describing (or which might describe) randomised, double-blind, placebo-controlled trials of kava extract for anxiety were sought through electronic searches on EMBASE, MEDLINE, AMED (British Library), CISCOM (Research Council for Complementary Medicine, London), Central/CCTR and CCDANCTR. The search terms that were used were kava, kawa, kavain, Piper methysticum and Rauschpfeffer (German common name for Piper methysticum). Additionally, manufacturers of kava preparations and experts on the subject were contacted and asked to contribute published and unpublished material. Hand-searches of relevant medical journals (Erfahrungsheilkunde 1996 - 2002, Forsch Komplementärmed Klass Naturheilkd 1994 - 2002, Phytomed 1994 - 2002, Alt Comp Ther 1995 - 2002), conference proceedings (e.g. FACT - Focus on Alternative and Complementary Therapies 1996 - 2002) and our own files were conducted. The searches were updated to August 2002. No restrictions regarding the language of publication were imposed.

SELECTION CRITERIA

To be included studies were required to be randomised, controlled trials (RCTs), i.e. trials with a randomised generation of allocation sequences, and conducted placebo-controlled and double-blind, i.e. trials with blinding of patients and care providers. Trials using oral preparations containing kava extract as the only component (mono-preparation) were considered. Trials using single constituents of kava extract alone, assessing kava extract as one of several active components in a combination preparation or as a part of a combination therapy were excluded.

DATA COLLECTION AND ANALYSIS

Data were extracted systematically according to patient characteristics, interventions and results. Methodological quality of all trials was evaluated using the standard scoring system developed by Jadad and colleagues. The screening of studies, selection, data extraction, validation and the assessment of methodological quality were performed independently by the two reviewers. Disagreements in the evaluation of individual trials were resolved through discussion.

MAIN RESULTS

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 (weighted mean difference: 5.0, 95% confidence interval: 1.1 to 8.8; p = 0.01; n = 345). Adverse events as reported in the reviewed trials were mild, transient and infrequent.

REVIEWER'S CONCLUSIONS

Compared with placebo, kava extract appears to be an effective symptomatic treatment option for anxiety. The data available from the reviewed studies suggest that kava is relatively safe for short-term treatment (1 to 24 weeks), although more information is required. Further rigorous investigations, particularly into the long-term safety profile of kava are warranted.