Kava is a South Pacific native plant locally used as a traditional medicinal ingredient. The cold water root extract of this plant is an effective treatment for anxiety, muscular spasms, stress, pain, and menstrual disorders. There is a long history of using Kava as a beverage in the South Pacific regions. [1] Gradually, this beverage gets international acceptance due to its anxiolytic effect. But commercial preparation of Kava for recreational purposes unable to serve the medicinal benefits because instead of water, alcohol is used in the kava root extraction process, which contains toxic chemical components. [2]
Traditionally, Kava beverage is from the peeled root/ rhizome of the authentic kava variety. Available information also reported that apart from this pure Kava beverage, sometime kava beverage is mixed with commercially prepared kava beverage. However, not only root, but sometime Kava stems, or other parts of the plant is also extracted to produce different varieties of Kava beverages. The components of these preparations are also varied depending upon the plant parts used in the preparation. [2]
There is a total of 19 lactones-based phytochemicals are derived from Kava. Among these six are major and thirteen are minor. [3] The six lipophilic kavalactones including kawain, dihydrokawain, methysticin, dihydromethysticin, desmethoxyyangonin, and yangonin are the major phytochemical composition of Kava. [4] Among these six major phytochemicals, kawain and dihydrokawain are two principal components responsible therapeutic benefits of Kava. [1] Apart from these, the trace amount of alkaloids like pipermethysticine, methoxy cinnamoyl pyrrolidine, 3,4-epoxy-5-pipermethystine α, and awaine are also present in this herb. Other significant phytochemical composition of kava includes three flavokavains and flavokavain A-C. [3]
Kawain and dihydrokawain present in Kava has the strongest anxiolytic effect. Researchers suggested that kavalactone primarily acts on limbic structures of the brain to exerts neurological benefits. The neurobiological activity of kavalactones responsible for the anxiolytic effect occurs due to gamma-aminobutyric acid (GABA) receptors modulation. The various mechanism involves in this process include blockage of voltage-gated sodium ion channels, reduction of excitatory neurotransmitter release due to calcium ion channels obstacle, and enhancement of GABA type A receptors binding with the ligand.
Kava can also reversibly inhibits monoamine oxidase B, cyclo-oxygenase and reduces Kava can also reversibly inhibits monoamine oxidase B, cyclo-oxygenase and reduces dopamine and noradrenalin reuptake in neuronal tissue and prefrontal cortex respectively. This noradrenergic mechanism of the action exerted by Kava is responsible for behavioral effects that occur after the consumption of alcohol and benzodiazepines.
Altogether, the GABA modulation effect with increased noradrenergic activation gives a feeling of physical relaxation, mental pleasure with no cognitive deleterious effect. [1]
Cis-yagonin and flavokavain B are two bioactive phytochemicals present in Kava that have an anti-cancer effect. [3]
There are certain herbal preparations are mentioned in traditional medicinal use purposes:
Apart from these Kava Powder, Kava tinctur and Kava beverages are also available in herbal stores.
Anxiety relieve is the primary therapeutic benefits of Kava. The kava is popular traditional medicine for anxiety disorders as authentic Kava preparation is clinically efficacious and safe within the mild to moderate dose range. It’s nutraceutical approaches appeal to researchers to use this herbal medicine for preparing conventional medicinal product also. [1]
The biological activity of Kava also supports its anxiolytic, local anesthetic properties, anticonvulsive, sedative, antimycotic, analgesic, antispasmodic, and central muscular relaxing effects due to the presence of kavalactones in it. In European and North America countries, Kava is widely used as an herbal regimen for anxiety disorders treatment. [3]
Generalized anxiety disorder is a mental condition with cognitive and somatic symptomatology. This condition is primarily associated with chronic, excessive worry and anticipatory anxiety. Along with this, the affected patients have a common complaint of sleep disturbance, fatigue, restlessness, irritability, concentration difficulties, edginess and muscular tension, etc. The available pharmacotherapeutic products do not have excellent clinical effects. The prescribed treatment can only provide moderate symptomatic relief for a temporary basis with a high risk of undesirable side effects burden. Recommended psychotherapeutic treatments are relatively more efficacious, but doctors have prescribed them to very limited patients due to tolerability issues. [1]
Kava treatment helps to modulate neurotransmitters and provides beneficial effects against generalized anxiety disorder. Kava administration alters the GABA metabolites properties in limbic brain regions in the generalized anxiety disorder. This neurobiological efficacy of kava administration helps to provide mental relaxation. In summary, authentic safe and efficacious traditional Kava extract of kava is considered as a ‘Level 1’ treatment option for patients suffering from anxiety disorders and provide significant benefit. This treatment helps easy economical treatment options for patients belongs to Pacific Island nations. [1]
A research result reported Kava is effective against leukemia and ovarian tumor effect due to its anti-cancer effect. [3]
Few randomized controlled clinical trial results suggested that kava is effective to reduce anxiety in perimenopausal women, and facilitates cognitive function. It improves sleep quality and increases positive mental condition. [6]
Many research results reported Kava has hepato-toxic effects like hepatitis, liver cirrhosis, functional disturbances, and liver failure in humans. Britain, Canada, France, Germany, Switzerland are the countries where Kava has banned due to these serious adverse effects. In the USA, FDA does not interfere with the Kava consumption, however the general public of this country concern about liver-related side effects. [7]