Background: In an acute hospital setting, a multi-disciplinary approach to medication review can improve prescribing and medicine selection in patients with frailty. There is a need for a clear understanding of the roles and responsibilities of pharmacists to ensure that interventions have the greatest impact on patient care. Aim: To use a consensus building process to produce guidance for pharmacists to support the identification of patients at risk from their medicines, and to articulate expected actions and escalation processes. Methods: A literature search was conducted and evidence used to establish a set of ten scenarios often encountered in hospitalised patients, with six or more possible actions. Four consultant physicians and four senior pharmacists ranked their levels of agreement with the listed actions. The process was redrafted and repeated until consensus was reached and interventions were defined. Outcome: Generalised guidance for reviewing older adults' medicines was developed, alongside escalation processes that should be followed in a specific set of clinical situations. The panel agreed that both pharmacists and physicians have an active role to play in medication review, and face-to-face communication is always preferable to facilitate informed decision making. Only prescribers should deprescribe, however pharmacists who are not also trained as prescribers may temporarily "hold" medications in the best interests of the patient with appropriate documentation and a follow up discussion with the prescribing team. The consensus was that a combination of age, problematic polypharmacy, and the presence of medication-related problems, were the most important factors in the identification of patients who would benefit most from a comprehensive medication review. Conclusions: Guidance on the identification of patients on inappropriate medicines, and subsequent pharmacist-led intervention to prompt and promote deprescribing, has been developed for implementation in an acute hospital.