Kava, also known as Kava root or Kava Kava or Kava Pepper, is an herb native to the South Pacific islands and has been used both medicinally and recreationally as a hypnotic, psychotropic, and anxiolytic (anxiety reducer) for hundreds of years. Its botanical name is Piper methysticum. There are pleasant and mild psychoactive and hypnotic effects in it when its roots are brewed into a beverage, and is sometimes paired with alcohol and treated in a manner much like alcohol and historically used as a relaxant. The active ingredients called kavalactones found in the kava shrub have beneficial effects including anxiolytic (anxiety-reducing) effects. It is also considered as a cognitive enhancer, but not absolutely safe. 
Though, nowadays, Kava is used as an herbal supplement, traditionally, the roots of this herb were prepared into a beverage and used in social ceremonies and rituals to promote relaxation. It has been used in traditional medicine practices for variety of health benefits, but this plant extract has mainly been used in the treatment of anxiety disorders. Besides, Kava has been consumed for alleviating feelings of nervousness or worry, promoting energy levels, curbing hunger cravings, supporting digestive health, reducing headaches, and reducing inflammation.
The common health benefits of Kava include:
- Reduces anxiety 
- Helps people fight cancer 
- Promotes sleep 
- Alleviates depression 
- Helps people who have attention deficit hyperactivity disorder (ADHD) 
- Improves physical health 
- Helps with urinary tract infections 
- Helps with epilepsy 
- Improves menstrual discomfort 
- Increase sexual desire 
- Enhances cognitive performance 
- Improves mood 
- Reduces headaches 
- Reduces inflammation 
Though modern research has demonstrated a number of health-boosting properties in this herb, there is still limited research available to evaluate its therapeutic efficacy.
How it works
Most of the research to date has focused on kava’s potential to reduce anxiety. Kava’s biological effects, due to a mixture of compounds called kavalactones, are reported to include sedative, anxiolytic, antistress, analgesic, local anaesthetic, anticonvulsant and neuroprotective properties. The pharmacological properties of kava are postulated to include blockade of voltage-gated sodium ion channels, enhanced ligand binding to gamma-aminobutyric acid (GABA) type A receptors, diminished excitatory neurotransmitter release due to calcium ion channel blockade, reduced neuronal reuptake of noradrenaline (norepinephrine), reversible inhibition of monoamine oxidase B and suppression of the synthesis of the eicosanoid thromboxane A(2), which antagonises GABA(A) receptor function.
Kava seems to affect the brain and other parts of the central nervous system. Its active ingredients – kavalactones are believed to be responsible for its effects. Kavalactones readily cross the blood brain barrier and after oral ingestion can exert effects in under an hour.
Though kava may be beneficial for anxiety and have many other therapeutic benefits, there are causes to be concerned about its potential side effects. In the early 2000s, several cases of liver toxicity were reported related to kava consumption. And later the US Food and Drug Administration warned about the risk of liver damage associated with kava. In many countries including Germany, Switzerland, France, Canada and the UK, Kava use has been banned or restricted.
You are advised not to use kava if you are pregnant or breast-feeding. Also don’t use it if you have Parkinson’s disease. As it may interact with some medications, stop using kava at least 2 weeks before a scheduled surgery.
As the FDA has not issued standard dosage guidelines for Kava, the best source of information on how much to take comes from clinical research studies. Kava dosages can be different depending on the symptoms.
For depression and anxiety disorders, it is suggested to take 400-500 milligrams daily divided into 3 equal doses. For promoting sleep and insomnia relief, you can normally take 100 milligrams just once daily before bedtime. For your appropriate doses, consult your physician and healthcare provider.