Kava kava is an herbal remedy that some people use to relieve stress and anxiety and boost sleep. However, some research suggests it may cause liver damage, so individuals should use it with caution.

Kava kava, or simply kava, has a long history of use in alternative medicine and traditional ceremonies. People traditionally mix kava kava with water or boil it into tea, but it can also come as a tablet.

Some research suggests kava kava has a mild anxiety-reducing effect, but it may also cause severe liver damage.

It is still legal to sell kava kava in the United States, but the Food and Drug Administration (FDA) suggests that people should use it with caution.

This article explores kava kava’s uses, benefits, and safety, including drug interactions and how to use it.

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Kava kava comes from the Piper methysticum plant, which is native to islands of the Pacific Ocean. Traditionally, people made a paste from the plant’s root and mixed it with water or coconut milk to create a drink.

People native to the South Pacific islands use this kava kava drink during cultural and religious ceremonies to create a state of inebriation. People can also make powder or tablets from the dried roots.

The active ingredient in kava kava, kavalactones, may cause a person to feel relaxed, talkative, and euphoric. Some people describe its effects as similar to alcohol while allowing a person to retain mental clarity.

People may use kava kava to relieve anxiety and promote sleep.

Anti-anxiety effects

Research into kava primarily focuses on its use for relieving stress and anxiety.

A 2020 review highlights several clinical trials suggesting 20 to 300 milligrams (mg) of kavalactones is effective at relieving mild and moderate anxiety.

A 2018 systematic review of clinical trials found that kava was more effective at treating anxiety in three out of seven trials. The authors suggest kava may be effective for short-term anxiety relief but is not a long-term treatment.

A 2019 study compared kava with a placebo over 16 weeks in people with generalized anxiety disorder. However, the results revealed no significant difference in anxiety reduction using this particular kava extract.

Sleep-promoting effects

A 2020 review highlights that kava may help to induce sleep and improve sleep quality, including increasing the amount of deep sleep someone gets.

Kava may also have some benefits for people with sleep disorders. However, further research is necessary to understand and support these claims.

Other uses

Other potential benefits of kava in the 2020 review include:

  • reducing cravings for addictive substances, such as alcohol and drugs
  • improvements in memory
  • anticancer activity

Kava may also help to relieve menopause symptoms and improve libido in females.

However, more research is necessary to support and strengthen these potential benefits.

Research links kava kava use to liver damage. Although, the exact frequency and cause of liver damage is unknown.

Because of this, authorities in several countries, including Canada, Great Britain, and Germany, have restricted or banned kava kava.

Kava kava is still legal in the U.S. due to its possible uses as a treatment. However, in 2002, the FDA directly warned consumers that kava-based products could cause liver damage. Some of this damage, such as that caused by hepatitis and liver failure, can be severe.

Potential causes for kava liver toxicity include low quality cultivars, interactions with other drugs, and certain chemical compounds.

A 2020 review suggests that traditional kava use may not have the same risk of liver damage, which may highlight the importance of the preparation method. However, the authors emphasize the need for more research trials.

Until researchers know more about the safety of kava kava, people should remain cautious when using it.

Side effects of kava kava

Potential side effects of kava use include:

There has been little research into the effects of kava in people who are pregnant.

However, the National Center for Complementary and Integrative Health states that kava kava may pose risks for people who are pregnant or breastfeeding.

Until more definitive research is available on its safety, it may be best to avoid using kava during pregnancy.

Traditionally, people grind dried kava kava root into a powder and mix it with water or coconut milk. It may also be possible to buy premade kava tea from some stores.

The drug can come in liquid form and mix with other drinks such as juice. There are also tablets and capsules of powdered kava kava available.

Clinical trials in a 2020 review suggest that daily doses between 20 and 300 mg of kava kava may be effective for anxiety.

The review highlights a daily recommendation of 60 to 250 mg of kava in the form of dietary supplements for adults.

People can speak with a healthcare professional for more information about the best potential dose of kava kava for them.

A 2020 review highlights the potential interaction between kava kava and alcohol. Animal studies have also suggested a potential herb-drug interaction.

The concern for drug interactions may be more significant for medications with overlapping sedative effects of potential for liver damage.

People should always speak with a healthcare professional before taking a new supplement, especially if they are currently taking medication.

What does kava kava do to the body?

Kava kava may have anti-inflammatory properties that may contribute to effects such as pain relief. Research highlights kava’s potential for inducing physical and psychological relaxation.

However, research also links kava kava to liver damage, which can be fatal.

Is kava safer than alcohol?

A 2020 review suggests that kava kava may reduce cravings associated with alcohol and other addictive substances. However, research also associates liver damage with certain types of kava preparation.

More research is necessary to determine whether kava enhances the risk of liver damage from other toxins, such as alcohol.

Does kava knock a person out?

According to a 2022 article, kava kava has sedative and anesthetic properties. Some people may use kava kava to help with sleep conditions, such as insomnia.

Kava kava is an herbal remedy that people may use to relieve anxiety and promote sleep. However, some research suggests that kava kava can cause severe liver damage.

Several countries have banned or restricted products containing this ingredient, but it is still legal in the United States. That said, the FDA has cautioned against its use.

Because of these concerns, people may want to speak with their doctor about other herbal remedies and lifestyle changes to relieve anxiety and improve sleep.