Second Career for Grayanotoxins
Natural products are not necessarily gentle medicines. A famous example is the so-called “Chinese nephropathy”. In 1993, nephrotoxicity of more than 100 women under the age of 50 was observed in Belgium as a consequence of herbal poisoning. The use of Chinese herbs containing aristolochia acid in a slimming regime resulted in extensive interstitial fibrosis of the kidney, which led to renal failure and in some cases to renal urotheliomas [1,2]. Although not all potentially toxic substances cause such strong side effects, there is still uncertainty about herbal products and reports about contaminations and adverse side effects might sometimes leave a bad after taste about the use of herbal products [3,4].