... NatlAcad Sci USA 96: 10104–10108.10 Interactions of Bioactive Plant Metabolites 229Fidler, M., Kern, S.E. 2006. Flexible interaction model for complex interactions of multiple anes-thetics. ... termed antagonistic. If the effect is equal to the expected effect(i.e., there is no interaction) , the interaction is termed additive (see Greco et al.,1995; Spelman, 2007, in Cseke et al., ... additivity.In the following sections we explore physical models of drug interaction, discussa mathematical model that can be used to assess interactions, and provide a numberof examples of plant compounds...