Objective: To assess efficacy and safety of citalopram compared to quetiapine and olanzapine for the treatment of agitation in patients with Alzheimer disease (AD)., Design: Longitudinal, 6-month study., Setting: Nursing home (NH)., Participants: 75 NH residents with AD and agitation, randomized to citalopram (n = 25), quetiapine (n = 25), or olanzapine (n = 25)., Measurements: Changes in Neuropsychiatric Inventory (NPI) agitation subscale score and the modified Alzheimer Disease Cooperative Study-Clinical Global Impression of Change (mADCS-CGIC) were used to assess treatment efficacy. Participants were surveilled for adverse health outcomes., Results: Citalopram treatment (30±5.8 mg/d) resulted in similar 6-month efficacy compared to both quetiapine (94.0±40.4 mg/d) and olanzapine (5.2±1.6 mg/d), lower occurrence of falls than olanzapine [odds ratio (OR) = 0.81, 95% confidence interval (CI) = 0.68-0.97, P = .012], lower incidence of orthostatic hypotension than both quetiapine (OR = 0.80, 95% CI = 0.66-0.95, P = .032) and olanzapine (OR = 0.75, 95% CI = 0.69-0.91, P = .02), and less all-cause hospitalizations than both quetiapine (OR = 0.92, 95% CI = 0.88-0.95, P = .016) and olanzapine (OR = 0.78, 95% CI = 0.64-0.92, P = .004), after multiple adjustment for potentially confounding variables. No differences were observed for cognitive and functional decline, QTc prolongation, and infections., Conclusions: Citalopram resulted in similar efficacy and less adverse outcomes when compared to 2 atypical antipsychotics for treatment of agitation in NH residents with AD. Replication of these findings and assessment of long-term efficacy and safety of citalopram for treatment of neuropsychiatric symptoms in dementia are needed., (Copyright © 2017 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.)