RESUMO
There is a great enthusiasm for herbal medications with increasing and widespread use among the population in various countries. A certain scepticism towards the use of pharmaceutical drugs may promote the use of herbal medicines such as echinacea, ginger, garlic, ginkgo, cranberry, valerian or St. John's wort even in western countries. Although considered safe among users, adverse effects such as increased bleeding tendencies, hypertension and hepatotoxicity can occur. Physicians should caution patients on the adverse side effects of herbal medicines and interactions between herbal medicines and pharmaceutical drugs, leading to various and uncontrollable deterioration of vital functions in the perioperative period. Although evidence-based data are lacking, anaesthesiologists and surgeons should be familiar with the effects of herbal medicines and should enquire about the use of these agents in the preoperative assessment. Currently available data suggest that herbal medications should be discontinued up to 2 weeks before elective surgery, although no guidelines of scientific societies have yet been published.