["Dosis solum facit venenum" also for herbal products]

A report of severe hepatitis due to the use of material from the plant Chelidonium majus, reminds us that herbal products can be much more life-threatening than many people realise. The widespread use of plants for food has reinforced the idea that eating plants promotes health. With the development of organic chemistry in the 19th century it became possible for the first time to purify and identify pharmacologically active plant constituents and later on to synthesize related compounds with an even stronger activity. The development of the antimalarial artemotil from Artemisia plants is a recent example. The activity, safety and composition of such compounds can be controlled in just the same manner as purely synthetic compounds. However, some people still believe that traditional plants are much safer and better than modern synthetic pharmaceuticals. The qualitative and quantitative composition of such herbal medicines from alternative medical sources, are not covered by public health legislation. Whereas phytotherapists consider plants to be a source of useful drugs, regular physicians maintain that the composition of a preparation and not the provenance, determines its effects.