Intersections of historical disciplines create tensions within scales of historical writing.  In writing the military medical history of WWI, specific parameters are set, defining the work.  These criteria include differing types of scale.  To reconcile the tensions due to differing modes of scale, contractions and expansions of parameters must be addressed, and local and global perspectives are significant.  Using research from my PhD, this paper explores contractions and expansions in scale within different parameters: global supply issues to local medicine manufacturing; pre- and post-war martial and political concerns to the tightly defined four-year period of the war; from social and educational tensions in the wider pharmacy profession to the lack of commissions within a single branch of the armed forces.  In this paper I argue that while many of these tensions were obvious to historical actors themselves, they have been rendered irrelevant by subsequent historiographic frameworks that approached WWI subjects in narrower dimensions of scale.  By exploring wartime medicine supply at the intersection of military, medical and business history, I aim to reconcile the scales of analysis to chart the overlapping interests of pharmacists, military units, and professional regulatory bodies against dominion forces, national governments and imperial political directives.