Factors influencing the use of neuroleptic and other CNS-acting medications ('antidepressants' and 'hypnotics/anxiolytics') were examined in different elderly populations (> 65 years): long-stay care hospital subjects (n = 381), nursing home subjects (n = 1247), private residential home subjects (n = 321), statutory residential home subjects (n = 525), old age psychiatry facility subjects (n = 48), community dwellers (n = 97), in different geographical areas (urban n = 1223 and rural n = 1396). Neuroleptics were prescribed in 28% of the individuals, hypnotics/anxiolytics in 33% and antidepressants in 12%. Prescription of neuroleptics was significantly predicted by institutional placement (other than long-stay care hospital facility), lower cognitive function and rural geographical area. Age greater than 75 years and lower functional score (lower dependency) significantly decreased the likelihood of receipt of neuroleptics. Antidepressant use was significantly less likely in male subjects, patients with cognitive impairment and patients greater than 85 years. Institutional placement (other than long-stay care hospital facility and old age psychiatry facility) and rural locality predicted increased likelihood of antidepressant prescription. Institutional placement (other than long-stay care hospital facility) and geographical (rural) location were significant independent predictors of hypnotic/anxiolytic use. Prescription of hypnotic/anxiolytic drug class was significantly less likely in those individuals with lower cognitive status. In this representative elderly cohort, patient characteristics: age, sex, cognitive score, functional score, place of residence and geographical location markedly influenced drug utilisation.