AbstractBackground: Delirium is an acute and typically reversible failure of essential cognitive and attentional functions and is a growing public health concern, with an incidence of 20–50% in patients older than 65 after major surgery and 61% in patients undergoing hip fracture surgery. Numerous treatment strategies have been examined with no conclusive results. The purpose of this study is to assess the efficacy of a three-day low-dose risperidone treatment protocol, 0.5 mg BID, in treating delirium in elderly hospitalized orthopedic surgery department patients.Methods: This study is a prospective non-randomized study involving the senior patient population, older than 65, in an Orthopedic Surgery Department in 2019 and 2020. Delirium was diagnosed by a confusion assessment method (CAM) questionnaire. A three-day 0.5 mg risperidone BID treatment protocol was initiated following diagnosis. Patient data collected included age, gender, chronic diseases, type of surgery and anesthesia and delirium characteristics.Results: The delirium study group included 47 patients with an average age of 84.4 years (±8.6), of whom 53.2% were females. Delirium incidence was 3.7% in all patients older than 65 (1759 patients) and 9.3% in the proximal femoral fracture group. We did not correlate electrolyte imbalance, anemia, polypharmacy and chronic diseases to delirium onset characteristics. Following the three-day low-dose risperidone treatment protocol, 0.5 mg BID, 14.9% of the patients showed CAM score normalization after one day of treatment, and 93.6% within two days.Conclusions: We found our rigid three-day low-dose risperidone treatment protocol, 0.5 mg BID, efficacious in fast delirium resolution, without side effects.