Editorial [Hot Topic:Molecular Mechanisms of and Clinical Evidence for Interactions Between Natural Products and Drugs (Guest Editor: Thomas Efferth)]

Although medicinal herbal products gradually lost importance in the course of chemistry's progress in industrialized countries during the 20th century, the current thriving revival of phytotherapy is followed by an increasing scientific interest in bioactive compounds as lead drugs for semi-synthetic modification. On the other side, it must not be overseen that natural products are still a major resource for drug development and represent a significant segment on the pharmaceutical market as compared to randomly synthesized compounds. About one quarter of all drugs in modern pharmacopeia derives from plants. In the course of this increasing interest both in the public to use natural herbal products as well as in science to understand the modes of action, it is becoming more and more clear that herbal products can interact with standard drugs. These interactions can lead to synergistic or antagonistic effects and might be beneficial or disadvantageous for the human body depending on the specific conditions. It is out of discussion that herbs are not “gentle medicine” without any side effects. The old rule in pharmacology that every active drug has both wanted pharmacological effects and unwanted toxic side effects holds also true for herbal medicines. This is quite logic and meaningful, if one recalls that plants produce chemical compounds in their secondary metabolism as defence weapons towards hervibores and microorganisms. Therefore, the careful investigation of actions in the human body including interaction with other drugs is mandatory. I was fortunate to team up a panel of reputed experts from different fields in pharmacy, biology, and medicine to highlight important aspects of the interaction of natural products with drugs. This Hot Topic Issue of “Current Drug Metabolism” on “Molecular mechanisms and clinical evidence for interactions between natural products and drugs” is organized in two main parts. The first part is molecular pharmacology with contributions of Michael Wink, Adorjan Aszalos, Gert Fricker, Ji Zhang and their co-workers as well as my own group. These topics are more related to basic science. The second part is clinically oriented with contributions of the teams of Sunita Vohra, Peter de Smet and Cathrine Ulbricht......