Kava is a psychoactive drink and herbal medicine made from the root or rhizome of Piper methysticum. Pacific communities have prepared and shared it for centuries in social, ceremonial and cultural settings. That living tradition should not be reduced to a generic “relaxation supplement”.
The effects of kava come mainly from compounds called kavalactones. They can produce mouth numbness, muscle relaxation, drowsiness and reduced coordination. Human trials have studied some standardised extracts for anxiety symptoms, but results are mixed and preparation-specific. Kava is not established as a safe treatment for an anxiety disorder, insomnia or another mental illness.
Kava may harm the liver. It can also impair driving and interact with alcohol, sedatives and medicines. A traditional cold-water kava drink, a capsule, kava powder, kava tea and a concentrated extract are not interchangeable.
Written by: Charles Gumbley, BHSc Clinical Nutrition, DipHSc Western Herbal Medicine. Evidence checked: 20 July 2026.
Benefits of Kava: What Human Anxiety Trials Show
The most studied potential benefits relate to short-term anxiety symptoms. A 2018 systematic review included seven placebo-controlled trials. Three reported a benefit, and a pooled responder analysis across five small trials favoured kava. The review did not establish long-term effectiveness or rule out rare liver toxicity.
A larger 16-week randomised trial then tested kava for generalised anxiety disorder. Remission occurred in 17.4% of the kava group and 23.8% of the placebo group, a non-significant difference. Abnormal liver function tests were significantly more frequent with kava, although no participant met the trial definition for herb-induced liver injury.
These findings do not support marketing kava extract for treating anxiety. The TGA has previously required a kava sponsor to remove unsupported generalised-anxiety and no-liver-harm claims. Mental-illness representations in therapeutic-good advertising are restricted. Seek professional assessment for persistent anxiety, panic, low mood or impaired daily function.
Research cannot be transferred freely between products. Trials have used named extracts at defined active-compound amounts. Results from an anxiolytic kava extract do not establish the effects of a cup of kava, a tincture, a beverage from a kava bar or an unrelated dietary supplement.
Use of Kava: Root, Kavalactones and Product Differences
Kava has a long history in the South Pacific. Traditional aqueous kava is generally prepared by suspending peeled root material in water. The kava plant has many cultivars, and chemistry varies with cultivar, plant part, age, processing and storage. “Noble” is a cultivar classification, not proof that a product is risk-free.
Kavalactones in kava include kavain, dihydrokavain, methysticin, dihydromethysticin, yangonin and desmethoxyyangonin. Their proportions influence a preparation’s chemical profile. Other compounds in kava, contaminants, non-root plant parts and extraction solvents may also matter. A fresh-root equivalent on a label is not the same as a measured dose of kavalactones.
Different kava products include cold-water beverages, dried root, teabags, tablets and capsules. Alcoholic or organic-solvent extracts are chemically different from traditional water preparations. “Herbal tea” is often used loosely; in Australia, a therapeutic teabag and a food beverage sit under different rules.
The Food Standards Code permits food kava only as dried or raw root or as a beverage made by cold-water suspension of root without organic solvents. The label must state “use in moderation” and “may cause drowsiness”. Commercial food importation requires an Office of Drug Control permit; passenger and Northern Territory rules differ.
Types of Kava, Product Quality and Preparation
The label should identify kava root or rhizome, cultivar where known, extraction solvent, plant-to-extract ratio and active amount. Kava supplements described only by a large “fresh equivalent” can conceal the information needed to compare formulations. A kava tincture may use alcohol; aqueous kava extracts use water. Neither should be assumed equivalent to a traditional beverage.
Quality concerns include substitution, mould, microbes, pesticides, non-root material and poor storage. Demand for kava can put pressure on supply chains, making cultivar and batch traceability relevant. Independent identity and contaminant testing adds useful assurance but cannot remove the pharmacological risks of kava.
Kava bars and online sellers may use terms such as noble, instant, micronised or ceremonial. These are not a universal safety certification. Regular kava drinkers can also develop tolerance to some subjective effects while remaining exposed to sedation, interactions or heavy-consumption harms.
Kava consumption should be measured in the actual serving and kavalactone content, not marketing language. Do not copy amounts of kava from a trial or another product. To use kava safely, follow an Australian-compliant label and obtain individual advice when any medicine or health condition is involved.
Form of Kava Medicine: Australian Dose and Label Rules
Australian listed medicines containing oral Piper methysticum are restricted to root or rhizome in tablets, capsules or teabags and specified aqueous preparations. Current permissible-ingredient rules cap the recommended daily amount at 250 mg of kavalactones and each tablet or capsule at 125 mg.
When an oral dose contains more than 25 mg of kavalactones, the label must state that it is not for prolonged use, that persistent symptoms require practitioner advice, that it is not recommended during pregnancy or breastfeeding, and that it may harm the liver. These are regulatory ceilings and warnings, not a recommended dose of kava or proof that every lower amount is safe.
Check the ARTG number, plant part, extraction method, kavalactone amount per dose, directions and complete warning panel. A kava product should not be purchased from a listing that omits a mandatory warning or makes claims beyond its approved indications.
Safety of Kava: Liver Toxicity, Sedation and Interactions
Reports of kava hepatotoxicity have included hepatitis, liver failure, transplantation and death, although causality and the contribution of preparation, contaminants, dose and other substances vary between cases. Rare events can be missed by small, short trials. Normal liver enzymes in one study do not prove absence of liver damage in wider use.
Stop kava and seek urgent medical advice for yellow skin or eyes, dark urine, pale stools, unusual fatigue, nausea, appetite loss, itching or upper abdominal pain. Do not use it with liver disease or an unexplained liver-test abnormality unless a suitably qualified clinician specifically directs it.
Kava has dose-dependent depressant effects on the central nervous system. Potential side effects include drowsiness, dizziness, nausea, mouth numbness, muscle weakness and impaired coordination. Heavy or prolonged kava use has been associated with a dry, scaly eruption called kava dermopathy, weight and nutrition problems, red eyes and fatigue.
Do not combine alcohol with kava. It may intensify alcohol, benzodiazepines, barbiturates and other sedatives. Interactions between kava and levodopa, anticonvulsants, antipsychotics, MAO inhibitors, antiplatelet or anticoagulant medicines and other drugs are possible. Ask a pharmacist to review all medicines and supplements. Avoid before surgery unless the treating team provides instructions.
Do not drive or operate machinery after taking kava. Young people, pregnant or breastfeeding people and anyone with liver disease should avoid unsupervised kava use. Long-term daily safety and a universally safe dose are not established.
Nutrition Market sells a kava medicine, creating a commercial conflict. No product is ranked or linked in this article until its full label, ARTG entry, approved indications, mandatory liver warning, stock, current cost and margin pass the governed feed checks.
Kava Questions
What does kava do for the body?
Kavalactones can depress central nervous system activity, producing relaxation, drowsiness, mouth numbness and reduced coordination. Small trials of selected extracts report mixed anxiety-symptom results. Kava can also cause adverse effects, interactions and rare serious liver injury.
Does kava get you stoned?
Kava is psychoactive but is not cannabis. Depending on the amount and form, drinking kava may cause relaxation, sedation, altered alertness, muscle weakness and impaired coordination. Feeling only mildly affected does not make driving safe.
Who should avoid using kava?
Avoid kava during pregnancy or breastfeeding, under 18 years, with liver disease, before driving, and with alcohol or sedative drugs. People using any medicine, preparing for surgery or experiencing mental-health symptoms should obtain individual clinical advice before they take kava.
Is kava healthier for you than alcohol?
That comparison is misleading. Kava and alcohol have different effects and risks; neither is risk-free, and combining them can increase intoxication, drowsiness, impaired reflexes and liver risk. Kava should not be promoted as a healthy substitute for alcohol.
Kava Benefits and Risks: References
- Ooi SL, Henderson P, Pak SC. The effectiveness and safety of kava kava for treating anxiety symptoms: a systematic review and analysis of randomised clinical trials. Journal of Alternative and Complementary Medicine. 2018;24(8):770–780. PMID 30396607. doi:10.1089/acm.2018.0001.
- Sarris J, et al. Kava for generalised anxiety disorder: a 16-week double-blind, randomised, placebo-controlled study. Australian & New Zealand Journal of Psychiatry. 2020;54(3):288–297. PMID 31813230. doi:10.1177/0004867419891246.
- Bian T, et al. Kava as a clinical nutrient: promises and challenges. Nutrients. 2020;12(10):3044. PMID 33027883. doi:10.3390/nu12103044.
- NSW Health. Kava clinical factsheet. Updated 5 December 2022.
- Food Standards Australia New Zealand. Proposal P1057: Review of the kava standard. Accessed 20 July 2026.
- Federal Register of Legislation. Therapeutic Goods (Permissible Ingredients) Determination (No. 1) 2026. Registered 26 February 2026.
- Office of Drug Control. Kava import requirements. Accessed 20 July 2026.
This article provides general educational information, not personalised medical advice. For suspected poisoning or an urgent interaction in Australia, call the Poisons Information Centre on 13 11 26; call 000 for an emergency.
