Hospital clinical-pharmacy services are commonly organised around wards, specialties, or fixed service lines because these structures support continuity, accountability, and integration with multidisciplinary teams. Yet medication-related demand is not spatially fixed. It can rise abruptly when organ function changes, high-risk treatment is initiated or intensified, interacting therapy is added, monitoring becomes inadequate, care transitions occur, or unresolved medication problems accumulate. Existing prioritisation tools show that patient and regimen characteristics can be used to rank pharmacy need, but their construction, validation, transportability, and implementation vary substantially. The evidence does not establish that a hospital-wide dynamic allocation strategy improves patient outcomes or pharmacist efficiency compared with geography-based coverage. A more defensible question is whether dynamic pharmacotherapy instability can identify episodes in which specialist reassessment is more likely to be needed, and whether acting on those signals improves targeting without damaging continuity or creating excessive false-positive workload. Pharmacotherapy instability is defined here as a time-varying state in which the likelihood that a medication regimen requires near-term pharmacist reassessment rises because medication exposure, patient physiology, treatment transitions, monitoring adequacy, interacting therapies, or unresolved medication problems are changing or unresolved. This construct should not be treated as a validated composite score. It is better regarded as a service-design proposition that requires measurable signals, explicit update rules, human interpretation, and comparative testing. The central implication is conditional: geography remains an important organisational scaffold, but fixed coverage may be insufficient when medication-management demand changes faster than ward boundaries can respond.
