According to the evaluated studies, Ginkgo biloba extract seems to be well tolerated with rates of adverse effects and study withdrawals not being different between medication and placebo. Nevertheless, it has to be taken into account that randomized controlled trials are not suitable to evaluate rare events and medication interactions. The included studies were undertaken with the standardized extract EGb 761®. However, other ginkgo extracts and ginkgo-containing products may be associated with different side effects. During intake of EGb 761®, mild gastro-intestinal symptoms, headache, dizziness or allergic skin reactions have occasionally been reported. Single cases of bleeding, e.g. intracranial haemorrhage, have been reported in the context of an intake of Ginkgo biloba preparations. However, some of these products concerned were of unknown origin and quality, some were multi-ingredient products, and in most instances anti-platelet agents or anticoagulants were taken in addition. A review of controlled studies indicated that the ginkgo extract EGb 761® does neither influence blood clotting nor bleeding time nor significantly potentiates the effects of anticoagulant or anti-platelet drugs [40]. In addition, a systematic review of case reports concluded that the clinical evidence for Ginkgo biloba causing bleeding is far from compelling [41,42].