Common Names: kava, kava kava, ava pepper, ava root, kawa

Latin Names: Piper methysticum


  • Kava is native to the islands of the western Pacific and is a member of the pepper family.
  • Pacific islanders have used kava for thousands of years as a medicine and for ritual purposes.
  • Today, kava is promoted as a dietary supplement for anxiety, insomnia, and other conditions.

How Much Do We Know?

  • There has been a fair amount of research in people on the use of kava for anxiety, but few studies have been done on other conditions.

What Have We Learned?

  • Kava supplements may have a small effect on reducing anxiety, but they have been linked to a risk of severe liver injury.
  • There isn’t enough evidence to show whether kava is helpful for any other conditions.

What Do We Know About Safety?

  • The use of kava has been linked to liver injury that is sometimes serious or even fatal. The exact cause and frequency of the liver damage are unclear.
  • Kava can cause digestive upset, headache, dizziness, and other side effects. The use of kava may affect the ability to drive or operate machinery. Long-term use of high doses of kava may cause kava dermopathy, a condition that involves dry, scaly, flaky skin with a yellow discoloration.
  • Kava may have special risks if taken during pregnancy or while breastfeeding because of the presence of harmful pyrone constituents.

Keep in Mind

  • Take charge of your health—talk with your health care providers about any complementary health approaches you use. Together, you can make shared, well-informed decisions.

What are other common names?

  • Piper methysticum
  • Ava
  • Ava Pepper
  • Ava Root
  • Awa
  • Gea
  • Gi
  • Intoxicating Long Pepper
  • Intoxicating Pepper
  • Kao
  • Kava Kava
  • Kava Pepper
  • Kava Root
  • Kava-kava
  • Kavain
  • Kawa
  • Kawa Kawa
  • Kawa Pepper
  • Kawain
  • Kew
  • Long Pepper
  • Rauschpfeffer
  • Sakau
  • Tonga
  • Wurzelstock
  • Yangona
  • Yaqona
  • Yaquon
  • Yongona

What is this product used for?

Kava is used by some people to help lower anxiety and as a sleep aid. Others use it to relax muscles. Some people may use this to help prevent cancer.

What are the precautions when taking this product?

  • Always check with your doctor before you use a natural product. Some products may not mix well with drugs or other natural products.
  • Be sure to tell your doctor that you take this product if you are scheduled for surgery or tests.
  • Do not use this product if you are pregnant or plan to become pregnant soon. Use birth control you can trust while taking this product.
  • Do not breastfeed while using this product.
  • Avoid beer, wine, and mixed drinks (alcohol) while taking this product.
  • This product may cause you to be sleepy. Take extra care driving and doing tasks that you need to be alert for.
  • Take extra care and check with your doctor if you have:
    • Kidney problems
    • Liver problems
    • Blood disorders
    • Parkinson's disease
    • Low mood

What should I watch for?

  • Upset stomach
  • Decreased amount of urine
  • Dizziness
  • Problems seeing
  • Loss of balance or problems walking
  • Mouth numbness
  • Scaly rash

When do I need to call the doctor?

  • Signs of a very bad reaction. These include wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat. Go to the ER right away.
  • Signs of liver problems. These include upset stomach or throwing up, belly pain, feeling tired, dark urine, yellow skin or eyes, not hungry.
  • Very bad throwing up
  • Very bad belly pain
  • Very bad loose stools
  • Very bad headache
  • Too tired or sleepy
  • Change in your ability to think clearly

Consumer information use

This information is not specific medical advice and does not replace information you receive from your healthcare provider. Only your healthcare provider has the knowledge and training to provide advice that is right for you. You should not rely on this information in deciding whether or not to use, or accept your healthcare provider’s advice regarding use of, any natural products or similar treatments, therapies, or life-style choices. This information does not endorse any natural products or similar treatments, therapies, or life-style choices as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information. It does NOT include all information about natural products, possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to you. You must talk with your healthcare provider for complete information about your health and treatment options.