Our study showcases the effective utilization of XRD-CT methodology in spatially resolving components with similar densities within pharmaceutical tablets, offering a detailed map of their composition. Despite the challenges posed by deciphering diffraction patterns of low symmetry systems and low molecular weight, we have successfully observed phase transitions directly in these tablets without resorting to sample manipulation such as trituration of tablet into powder, thus avoiding potential polymorphic transitions in the compounds. By employing a pressure-sensitive compound, we have pinpointed the precise locations of phase transitions and assessed the impact of compaction pressure on formulation. Notably, our approach has enabled both temporal and spatial resolution of changes occurring in these tablets. Furthermore, our investigation serendipitously uncovered a solid-state chemical reaction within the tablet, wherein the hydrolytic ring opening product of glycolide, 2-(2hydroxyacetoxy)acetic acid (HAA), was first identified using XRD-CT and subsequently confirmed through electron diffraction, culminating in the elucidation of its crystal structure. In the wider context of pharmaceutical research, our ability to apply this technique to pharmaceutically relevant formulations will enable a deeper, more intimate understanding of the effect of tableting pressure on