Side effects of phytotherapeutics in cancer care - consistencies and inconsistencies in national and international databases

Abstract

Abstract More than 80% of patients who had a cancer disease reported using phytotherapy. (8, 9) When using herbal medicine, knowledge of potential side effects is essential for counselling the patient. Purpose: The aim of this paper was therefore to collect information on the side effects of popular medicinal plants and to compare different official sources of information reporting on side effects of phytotherapeutics. Methods: Four different databases were reviewed from 09 February 2021 to 01 March 2022. These were the German monographs of the German Federal Institute for Drugs and Medical Devices (BfArM), the European monographs of the EMA, the website “About Herbs” and the Red List. One selected 171 plants of the German monographs with indications or effects that could be relevant for supportive cancer treatment. Results: Out of 171 selected plants, only twenty plants were found in all four sources. The compilation of the data shows a huge disparity of the number of plants listed as well as the type and frequency of side effects described. There is only one example where two sources agree: in case of Cynara cardunculus L., EMA and the Red List show the same side effects. Conclusion: In summary, physicians should not rely exclusively on one source, but should inform themselves about side effects on several sources to ensure the best possible safety for the patient. Since there seems to be too little data on certain medicinal plants for which no side effect has been documented, more clinical studies are needed.