Kava tablets are purported to reduce restlessness, promote feelings of tranquility, relax tense muscles and work as a natural sleep aid.
Kava (kava-kava) is a small shrub that grows natively in various islands in the Pacific Ocean, such as Fiji, Tonga, Tahiti, Hawaii and Vanuatu. It has been used medicinally for thousands of years.
The rhizomes (horizontal roots) and vertical roots of the plant are harvested and used to make kava beverages like juices and teas. The roots are also prepared as a ceremonial drink, consumed during social gatherings.
While traditionally consumed in the form of a drink, oral capsules and tablets are also commonly used as herbal remedies in alternative medicine practices. The Natural Medicines Comprehensive Database reports this herb has been used for depression, psychosis, cancer, pain and more.
Human research into the medicinal effects of this plant is currently limited, but preliminary studies suggest benefits for anxiety, stress and mood disorders. [1] Users describe it as having a pleasant, mild psychoactive and mood-lifting effect.



- Reduces feeling of anxiety & stress
- Improves feeling of wellbeing
- Shown to improve sleep & insomnia
Oral Kava Kava Tablets
Oral kava pills are used for relaxation, social anxiety stress reduction and mood improvement.
Root extract tablets and capsules are frequently used by those who do not enjoy the taste of kava juice or by people who prefer the convenience of a pill form.
The tablets typically contain highly-concentrated extracts from the roots of the plant, often standardized to between 30 – 70% kavalactone content. Lactones are the primary active constituents identified in the plant.
Kavalactones have been shown to influence GABAergic and Dopaminergic neuroreceptors in the brain. The active lactone chemicals isolated from organic kava roots include kavain, dihydrokavain, methysticin, dihydromyricetin and yangonin. [2]
Other standardizations exist including supplements formulated to provide 60-120mg of kavapyrones daily. The higher the concentration of active alkaloids, the stronger the effects will be.
Products can also contain different profiles of alkaloids, such as the 2-4-6 or 4-2-6 kavalactone extracts. This refers to the composition of specific alkaloids found in the extract in relation to each other.
Depending on the chemotype or strain of plant used, kava can produce stronger relaxing or sedating effects, increased social behavior, a creative state of mind, or a happy and energized state.
There is no significant difference in the effects of using kava in pill form versus drinking it as a beverage. While there may be slight differences in pharmacokinetics, the mechanisms of action are the same.
Many people enjoy kava’s taste and brew it as a beverage using bulk powder, liquid tinctures or Instant Kava drink mixes. Additives like honey, lemon, cinnamon and nutmeg are also used commonly to enhance the natural flavor of the roots.
Kava Tablets Reviews
User reviews of kava tablets posted online suggest that people experience improvements in energy levels, mood balance, sleep, pain relief and feelings of contentment when they take this product.
One user describes the product as providing potent anxiety relief and making their whole body feel relaxed and serene. This user said that it helps them to unwind after a long work week and is suitable as an alternative to alcohol.
Another user reported that Kava can clear mental chatter and make it easier to concentrate without being distracted. It is described as taking the edge off, without causing sedation or difficulty thinking clearly.
Another user said that it has helped to reduce their chronic muscle pain and is a great way to start the day.
A fourth reviewer reported that it promotes a strong euphoric feeling, makes you feel more sociable and has a mouth-numbing effect, but does not prevent normal daily function.
Not everyone experiences positive results when they take this product. There are reports of side effects such as gassiness, nausea, headaches, and discoordination when taken at high dosages.
Many of the negative reviews for Kava powder products mention a bad taste associated with consumption. However, oral tablets do not have a bitter taste as they are typically coated to mask the flavor.
Some users report that the product is not effective for their intended purposes. This may be due to unrealistic expectations of getting a “buzz” or “legal high” from the supplement. Kava does not cause a high sensation when used orally and appropriately.
Kava Kava Tablets for Anxiety
The German Commission E has approved the use of this herb for conditions of nervous anxiety, stress, and restlessness. This commission sets high standards for regulating the use of botanical drugs and herbal medicines in the country.
Research shows that taking kava root extract tablets can promote feelings of mental calm, sedation and anti-anxiety effects. Numerous clinical studies demonstrate that use of this herb can reduce symptoms in patients diagnosed with anxiety disorders.
Some research suggests that kava is an appropriate alternative treatment with efficacy comparable to that of tricyclic antidepressants and benzodiazepines. Kava has also been found safe and effective for long-term use, without a risk of tolerance or withdrawal symptoms. [4]
According to the Natural Medicines Comprehensive Database (NMCD), plant chemicals found in kava are believed to alter brain function and induce calmness by:
- Inhibiting the activities of an enzyme called monoamine oxidase B that breaks down mood-regulating neurotransmitters;
- Inhibiting neuronal reuptake of norepinephrine and dopamine;
- Influencing the structure of lipid membranes on neurons;
- Enhancing sodium channel functioning;
Kava has been shown to increase the expression of GABA receptors in certain parts of the brain. These receptors play a role in regulating anxiousness and preventing over-stimulation.
NMCD states that the pharmacological effects of kava extract including anti-anxiety, anti-inflammatory, anticonvulsant, antispasmodic, analgesic and sedative activities. [2]
Kava Benefits for Sleep
Some users report improvements in sleep quality when taking this supplement as well as making it easier to fall asleep faster. Preliminary evidence from clinical studies supports this usage.
Although researchers do not know exactly how kava works inside the Central Nervous System, it has been shown to induce sedative effects in animal studies. [2]
Other evidence suggests that kava may cause sedation by antagonizing dopamine, which is an excitatory neurotransmitter that regulates arousal.
The yangonin alkaloid found in the herb may be responsible for this effect. Therefore, oral tablets that contain higher concentrations of yangonin are more likely to produce a sedative effect. [2]
Studies are ongoing to determine how this supplement might be helpful for insomnia, restlessness, irritability and other related conditions. [1, 2]
Currently, the FDA has not approved the use of Kava as a sleep aid. More research is needed to determine efficacy.
How to Take Kava Tablets
Always take kava tablets or other kava supplements according to the manufacturer’s directions or under the supervision of your physician.
Different products will contain different dosages and formulations of active ingredients. Some forms of this herb are more potent than others and will require individuals to take a smaller amount to experience beneficial effects.
According to the Commission E monograph, if using a dry normalized extract containing 30% kavalactones, the recommended dosage is 200-400 mg per day. [4]
If using cut rhizomes, the recommended dosage is 1.7-3.4 g per day yielding 60-120 mg kava pyrones at a standard concentration of 3.5% (35 mg/g) alkaloids in the raw plant material.
Traditional preparations of this herb provide between 250-300 mg of active a-pyrones per serving. This is considered a high dose and may increase the risk of side effects or developing a feeling of intoxication.
Kava should not be used for more than three months without seeking medical advice. Some individuals report developing a tolerance to this herb while others say the effects become stronger with regular use.
Even if the plant extract is taken within suggested dosage guidelines, it is possible for users to experience delayed motor reflexes and impaired judgement while driving or operating heavy machinery. In some cases, people have been cited for driving infractions while under the influence of kava tablets.
This plant contains many different bioactive chemical compounds which may alter the effects and/or side effects of certain drugs and herbal supplements.
Some of the prescription medications that should not be used with kava unless under medical supervision include:
- P-glycoprotein substrate drugs including certain corticosteroids and calcium blockers;
- Cytochrome P450 1A2, 2C19, 2C9, 2D6, 2E1 and 3A4 substrates;
- Known hepatotoxic drugs like Precose, Tegretol and Allegra;
- Benzodiazepine drugs like Xanax, Valium and Lorazepam;
- CNS depressants including alcohol and barbiturates;
Other drug interactions are possible. Discuss all of the medications and herbal supplements you use with a doctor or pharmacist before beginning to take this product. [1, 2]
Possible Side Effects
According to the WHO and the Food and Agriculture Organization (FAO), “The weight-of-evidence from both a long history of use of kava beverage and from the more recent research findings indicates that it is possible for kava beverage to be consumed with an acceptably low level of health risk”.
Taking water-based kava root extracts is believed to be safe with a low frequency of adverse health effects. However, some ethanol-based extracts are linked to liver damage and must be avoided.
UMM states that anyone with liver dysfunction or liver disease should avoid using kava.
Between Europe and the US, there have been at least 25 cases of liver-related conditions (including cirrhosis, hepatitis, hepatocellular necrosis and death) associated with this supplement. [1]
Most of these cases are attributed to use of low-quality ethanol extracts of the plant or products made with the hepatotoxic aerial parts of the plant. Some cases were also linked to concomitant use of alcohol and other drugs.
Those with Parkinson’s disease, hepatitis and/or depression should seek medical advice before using kava supplements. Pregnant and/or nursing women are also advised not to use this product.
UMM states that this herbal extract should only be used under close medical supervision and for no more than 4 weeks consecutively before cycling off.
Some of the side effects associated with kava tablets and capsules include jaundice, headache, dark urine and chronic fatigue. Other possible adverse effects include nausea, vomiting, joint pain and poor appetite. [2]
Do not use kava tablets for at least two weeks before a scheduled surgery as it may elongate the effects of certain anesthetic agents. [2] [3]
Long-term and/or heavy use of kava tablets can cause the skin to become flaky, dry and discolored. Excessive use may also cause alopecia (hair loss), partial deafness and a lack of interest in eating. [3]
According to the German Commission E monograph, extended use can result in yellowing of the skin, hair and nails. It may also result in allergic skin reactions, pupil enlargement and disturbances in oculomotor equilibrium.
UMM advises all users to consult with their primary healthcare providers before beginning to take kava extract tables. Make sure you discuss all health conditions you have as well as any medications, supplements or psychoactive drugs you use.
- University of Maryland Medical Center
- Natural Medicines Comprehensive Database
- Sarris J1, LaPorte E, Schweitzer I. Kava: a comprehensive review of efficacy, safety, and psychopharmacology. Aust N Z J Psychiatry. 2011 Jan;45(1):27-35. doi: 10.3109/00048674.2010.522554. Epub 2010 Nov 15.
- Kava Kava rhizome (root). Herbal Medicine: Expanded Commission E. American Botanical Council.
Article last updated on: July 3rd, 2018 by Nootriment