Background: Psychotropic medication is widely prescribed in clinical practice for the management of behavioral and psychological symptoms of dementia (BPSD) in Alzheimer's disease (AD). However, there have been few pharmaco-epidemiological studies or studies conducted in a natural setting on the real use of antidepressants in AD. The aim of this survey was to assess the prevalence of antidepressant use in AD and to identify the clinical factors associated with antidepressant prescription.Methods: REAL.FR is a four-year, prospective, multi-center study. Baseline data including demographic characteristics, clinical variables and drug intake were obtained. Depressive symptoms were determined using the Neuropsychiatric Inventory (NPI).Results: A total of 686 AD patients were included. Antidepressant treatment was prescribed for 34.8% of patients. Clinically significant depressive symptoms (NPI ≥ 4) were observed in 20.5% of the total population. Although depressed subjects were significantly more likely to be treated with antidepressants than non-depressed subjects (p<0.0001), only 60% of depressed subjects overall were prescribed an antidepressant. In multivariate analysis, clinically significant depressive symptoms were associated with antidepressant prescription although this result was only observed in subjects without a previous history of depression.Conclusions: The available data on antidepressant efficacy in BPSD other than depression (in particular, agitation, aggression and, occasionally, psychotic symptoms) do not influence prescription choices. Depressive symptoms may be taken more seriously in the absence of a previous history of depression, leading to increased antidepressant prescription rates in individuals presenting with depression for the first time.