Kava: Consumer advice on kava

The Therapeutic Goods Administration (TGA) would like to alert you to emerging concern about medicines containing kava (also known as kava kava or Piper methysticum) following international reports linking use of medicines containing this substance with liver damage.

The TGA is recommending that anyone using kava-containing medicines should seek medical advice if they experience any unexplained symptoms. The following symptoms may be associated with liver problems:

• loss of appetite, unusual tiredness or mild fever;
• gastrointestinal symptoms including nausea, vomiting or abdominal discomfort;
• unexplained bruising or bleeding; and
• jaundice which is commonly associated with dark urine and yellowing of the skin and eyes.

Anyone at special risk of liver damage, such as those who have existing liver disease, should avoid kava-containing medications altogether. Little is known about the way kava interacts with other medicines and consumers should be cautious about taking these products while taking conventional medicines unless on the advice of a healthcare professional.

Reports from Germany and Switzerland have linked kava extracts with 30 serious cases of liver toxicity, some of which have resulted in the need for liver transplantation. The products implicated in these reports are medicines which contain chemically extracted ingredients of kava as opposed to kava in herbal form prepared by traditional methods (as used for ceremonial and recreational purposes by Pacific Islander and other cultural groups).

Based on these adverse reports, some European countries have withdrawn or are proposing to suspend the marketing authorisation of certain kava-containing medicines. In some countries manufacturers have either voluntarily withdrawn kava-containing medicines or their health authorities have alerted health professionals and consumers about potential liver toxicity problems with kava-containing medicines.

There have been no Australian cases of liver failure or related problems due to kava-containing medicines reported to the Adverse Drug Reaction Unit of the TGA. The strength of the association between kava-containing medicines and liver toxicity is still being evaluated and those patients most at risk are still to be identified. Until this information is available, the matter is being treated with great caution since liver toxicity is a serious safety concern.

Kava-containing medicines are promoted for a variety of uses, including insomnia and sleeplessness and relief of stress, anxiety and tension.