This study investigated a sieve classification method for evaluating carrier materials and particle size fractions, which could be a valuable tool in the early development of pharmaceutical dosage forms containing low-dose interactive mixtures. When developing new products based on interactive mixtures, it is essential to ensure that the drug particles are successfully deagglomerated and have adhered to the carrier particles. In this study, the effect on the demixing potential (DP) of low-dose interactive mixtures was assessed for various carrier particle sizes and surface textures. The model drug used was sodium salicylate and the tested carriers were lactose, mannitol, and isomalt. The results showed that the lowest DPs, i.e. the most mechanically stable mixtures, were obtained with lactose. Furthermore, for interactive mixtures, small carrier particles and/or a narrow carrier particle size range are essential for obtaining a low DP and high homogeneity. Calculation of the DP provided a reliable estimate of the quality of the low-dose interactive mixtures used in this study.