The herbal kava, taken to reduce stress and help people sleep, was worth around €100 million in product sales in Europe during 2001. However reports of a small number of adverse reactions, thought to be associated with the use of kava, led the BfArM (the German Federal Institute for Drugs and Medical Devices) to ban the sale of kava products in June 2002, closing the country's huge herbals market to kava trade. (Around half of all kava products were sold in Germany).
Since then France, Japan, UK, Australia, Canada, Switzerland and Singapore have followed Germany, with other countries implementing voluntary recalls.
Now, the the International Kava Executive Council, set up to lobby for kava's return to health food stores, has agreed with the German Health Ministry to carry out an additional toxicology test on an animal model, looking specifically at kava's effects on liver toxicity.
The results, likely to confirm the herbal's safety, according to Dr Joerg Gruenwald, executive director of the Europe-funded IKEC, could provide sufficient evidence for its return to other European markets.
"German requirements for herbal medicines tend to be much stricter than other countries like the UK or Netherlands. They have higher expectations of quality and efficacy. So we are pretty sure that if Germany accepts the new safety data, other countries will follow," Dr Gruenwald told NutraIngredients.com.
The UK's medicines regulator said at the time of its ban on the herb that it was aware of 70 world-wide reports of adverse liver reactions. In four of these cases the patients died and in seven cases the patients required liver transplants.
But kava experts condemned outright bans, claiming them to be a disproportionate response to the size of the alleged problem.
A major analysis of evidence on kava by Berlin-based Phytopharm Consulting found its efficacy and safety in the treatment of anxiety and stress to be proven by more than 20 clinical trials involving more than 10,000 patients.
"The severe hepatotoxic effects of kava, claimed by drug regulation authorities, cannot be regarded as clearly proven. Of the 76 reported cases that we re-evaluated, only four could possibly be linked to the intake of kava," said Gruenwald, one of the report authors, at the time.
Kava is prepared from the rootstock of the plant Piper methysticum originating from the South Pacific Islands. However it is thought that discrepancy in the varieties and parts of the plant used for extracts destined for Europe may have been responsible for some of the side effects.
The kava industry, predominately located in the islands of Vanuatu, Fiji, Samoa and Tonga, is expected to increase optimization of products and quality if it gains new trade.
The ban on kava in many countries destroyed the industry almost overnight and reduced Gross National Product (GNP) in producing countries by around 20 per cent, according to Tau'ili'ili Uili Meredith, Samoan ambassador to Germany and High Commissioner to the UK.
The new safety test is expected to be completed within the next six months.
In talks with IKEC earlier this month, UK Medicines and Healthcare Products Regulatory Agency (MHRA) reportedly expressed considerable interest in the German approach to creating new data, and advised that the Agency would consider the results of all new research.
German health authorities have also asked for a new clinical trial on kava to prove its efficacy. Kava had been available on a doctor's prescription.