Dr Rolf Spang, Switzerland
Four cases of severe hepatic complications associated with a kava root acetone extract occurred within a period of 7 months in Switzerland up to spring 2000. The incidence of severe hepatic complications can be estimated at around 1 in 35 000 patient-months in Switzerland and 1 in 175 000 patient-months globally.
Taking into account the benefits and available alternatives, the registration of the kava root acetone extract in Switzerland was provisionally suspended in September 2000 and definitely withdrawn in April 2001. The alcohol extract and a synthetic preparation containing 1-kavaine, with a seemingly lower incidence of severe liver reactions, have remained on the market, but were moved in autumn 2001 to “pharmacy only” status with a strong warning on the risk of liver injury and possible early symptoms.
While Switzerland is still receiving reports of severe liver reactions associated with the acetone extract, one recent case of hepatocellular injury has been attributed to a combination of the synthetic kavapyrone 1-kavaine combined with magnesium orotate and vitis viniferae extractum. In the meantime, several reports of severe hepatitis or liver injury associated with ethanol kava extract have been notified in other countries, most of them in Germany.
Kava extracts are not regulated as drugs in many countries. France, the United Kingdom and the United States have all taken different actions in the control of kava extract. Switzerland will decide on further action with respect to the ethanolic extract after examining the new international data.