Unplanned rehospitalizations occur frequently in older patients. Drug-related problems constitute a major and largely preventable cause with inappropriate prescribing being a substantial culprit. Solutions are needed to reduce this risk by targeting pharmacotherapy both during and after hospital stay. Therefore, we aim to perform a randomized controlled trial in geriatric inpatients to investigate the impact of a multifaceted clinical pharmacy intervention on health-related outcomes.; The study concerns a monocenter, non-blinded, randomized controlled trial that will take place at the acute geriatric wards of a large academic hospital. Patients being in a palliative stage with active therapy withdrawal or patients discharged to another ward within the same hospital or another hospital are excluded. In total, 828 patients will be randomized (1:1) to the usual care or intervention group. The multifaceted clinical pharmacy intervention comprises medication reconciliation at admission and discharge, medication review, patient/caregiver education, intensified communication with primary care providers and post-discharge follow-up, which also includes a telepharmacology service. The primary endpoint is defined as the time to an all-cause, unplanned hospital revisit within six months after discharge. Other health-related outcomes such as drug-related readmissions, quality of life and number of potentially inappropriate medications will be analyzed as secondary endpoints. Patient inclusion started in February 2021.; This study will provide useful insights regarding the impact of clinical pharmacy interventions on geriatric wards with the goal to optimize health-related outcomes such as hospital revisits.; ClinicalTrials.gov Identifier: NCT04617340.