Proposed model for phenytoin binding to HSA. The data in this report is consistent with a model in which phenytoin has direct binding at both the warfarin-azapropazone and tamoxifen sites, although it is possible that the competition noted in this study could have been due to negative plus positive allosteric effects between this drug and R-warfarin or cis-clomiphene. From Chen et al. (2004)  with permission of the authors and the publisher.
Salih et al. Nutrition Journal 2010 9:71 doi:10.1186/1475-2891-9-71