ABSTRACT
Preclinical and clinical studies have some limitations in the denition of the safety prole of a new drug. Information collected during these studies is incomplete for a variety of reasons. It is well known that animal tests are insufciently predictive of human safety, and that clinical trials are affected by qualitative and quantitative limitations regarding the identication of possible adverse drug reactions (ADRs). From a quantitative perspective, clinical trials enroll a limited number of patients for a limited observational period, not sufcient to identify rare events. Study samples may
21.1 Surveillance System of Drugs and Herbal Medicines ..................................405 21.1.1 Classication of Adverse Reactions to Drugs and Herbal Medicines ...408
21.2 Specic Pharmacovigilance Issues of Herbal Medicines and Essential Oils ...409 21.2.1 Safety Issues of Herbal Medicines ...................................................409 21.2.2 Phytovigilance .................................................................................. 410
