Objective: The number of pharmacists regularly working at geriatric health service facilities is limited, but many users of such facilities have multiple chronic conditions and receive continuous pharmacotherapy, simultaneously using numerous different types of oral drugs. We examined the outcomes of pharmacotherapeutic intervention provided by hospital pharmacists for geriatric health service facility users.Methods: We examinedthe outcomes of active pharmacotherapeutic intervention providedby hospital pharmacists for 154 facility users.Results: After the intervention, there were significant decreases in the mean number of types and price of drugs used, as they decreased from 7.38 to 6.17 and 368.3 to 309.2 yen/day, respectively. The number of prescription drugs changed was 300, and 206 of these changes were proposedby the pharmacists. The efficacy-basedcategories that these drugs belongedto widely ranged. The most frequent reasons for change were the “disappearance of symptoms”, “based on indications”, and “suspected adverse events”. Adverse events variedfrom mildto those that may leadto severe conditions.Conclusion: Pharmacotherapeutic interventions by pharmacists may optimize pharmacotherapy, reduce polypharmacy, and reduce the financial burden on geriatric health service facilities.