Kava kava ban: your questions answered

Kava kava is a herbal ingredient derived from the plant Piper methysticum, which is a member of the pepper family native to many Pacific Ocean islands.

The leaves and the root of the plant are used in herbal food and medicinal products. In recent years it has become popular in Europe in herbal remedies used to treat anxiety, tension and restlessness.

The majority of products that kava kava was used in are classed as herbal medicines and are regulated in the UK by the Medicines Control Agency (MCA). However, there were some food products containing kava kava, for example herbal tea bags, 'smoothie' drinks, cereal bars and vodka products. In addition, internet sites offered kava kava root and root powder for sale.

Evidence has mounted that in rare cases the use of products containing kava kava (mostly in the form of herbal medicines) has been associated with severe liver damage. The occurrence of liver damage is unpredictable and the mechanism is unclear.

To date, the Agency is aware of 110 cases of severe liver damage (hepatoxicity), possibly associated with the use of kava kava containing products. Eleven patients have suffered irreversible liver failure and received a liver transplant. Overall, nine patients have now died, including two who had received liver transplants.

The then Medicines Control Agency (MCA), now the Medicines and Healthcare products Regulatory Agency (MHRA) sought advice on kava kava from two groups of independent experts that advise them on the safety of medicines – the Committee on Safety of Medicines (CSM) and the Medicines Commission. Both found evidence of a risk, in rare cases, of liver damage associated with the use of unlicensed medicines containing kava kava and advised that they should be prohibited in order to protect public health.

Food Standards Agency scientists reviewed the data available to the CSM and MC and assessed the risks for food uses. The Chair of the Committee on Toxicity was consulted on these risks and agreed that consumption of kava kava may be associated with serious liver damage.

Following consultation with stakeholders, the Agency took the decision that, in the interests of protecting public health, it was necessary to ban the use of kava kava in foods.

Regulations ban the sale, possession for sale, offer, exposure or advertisement for sale, and the importation into England from outside the UK, of any food consisting of, or containing, kava kava.

The kava kava in Food (England) Regulations 2002 came into force on 13 January 2003.

The MHRA continues to advise against the use of herbal remedies containing kava kava, and in parallel action brought in legislation to ban its use in herbal products. The Medicines for Human Use (kava kava) (Prohibition) Order 2002 also came into force on 13 January 2003.

Since December 2001 the Food Standards Agency has advised against the consumption of foods containing kava kava. That advice remains unchanged.

Consumption of products containing kava kava poses a rare but serious risk to health. Bringing in these regulations is the only means by which we can adequately protect public health.

In 1990, the addition of tryptophan (an amino acid) to foods was banned in most cases. That action followed a relatively small number of cases of serious illness in people who were taking tryptophan in the form of dietary supplements. There are many cases of medicines that have been removed from the market due to liver toxicity. Following a review of scientific evidence, tryptophan has now been reintroduced to the UK market in the form of food supplements with an upper daily dose level of 220mg.

If any new evidence comes to light that suggests the ban is no longer necessary, the prohibition will be reviewed.

Kava kava products are available as medicinal products and foods. As such, responsibility for their regulation and control falls to the MHRA and the FSA respectively.

Yes. As with any other ban of this sort, if evidence comes to light suggesting the ban is no longer necessary in the interests of protecting public health the prohibition will be reviewed.

The 2005 consultation took place to fulfil a commitment made by Ministers, to review the available evidence relating to the safety of kava kava two years after the prohibition had been in place. A similar consultation was undertaken for kava kava in unlicensed herbal products by the MHRA.

Evidence was submitted by interested parties, and a review was undertaken of all new papers published since the original ban was put in place in 2002. Background papers are available from COT papers

Members of the Committee on Toxicity (COT) reviewed all the evidence presented to them. Background papers and minutes are available on COT background papers and minutes

Members considered that the new data were not sufficient to demonstrate the safety of food products containing kava kava, particularly considering the severe nature of the hepatoxicity linked with kava kava consumption. The new studies on metabolism did not help to identify a mechanism of hepatoxicity. Reports of hepatoxicity were still occurring, including cases related to traditional kava kava preparations. Concern was also expressed about the lack of controls over production of food such as the extraction method and the parts of the plant used in the extracts. Overall, members concluded that the new data did not warrant a change in their previous advice.