Background: Sleep complaints are frequent in old age. These difficulties are often associated with health-related problems, drug consumption, and the presence of mental disorders. Nonetheless, only sparse information is available on the clinical characteristics of elderly persons with insomnia. Aims: (a) To evaluate the prevalence of sleep problems among the elderly assessed in a psychogeriatric outpatient clinic; (b) to evaluate the association between the use of sleep tablets and sleep difficulties in this sample of patients. Methods: One hundred eighteen consecutive subjects were recruited from a psychogeriatric outpatient service in São Paulo, Brazil. Their sleep pattern was systematically assessed with the “sleep inventory,” a questionnaire consisting of 31 items that evaluate a number of sleep-related features. Clinical diagnoses followed the ICD-10 clinical descriptions and diagnostic guidelines. The number of drugs consumed by patients was also recorded. Results: Sleep complaints were highly prevalent (59.3%), with early morning awakening and nightmares being more frequent among patients with a depressive disorder. The use of sleep tablets was reported by 37.3% of subjects, and was associated with subjective sleep difficulties (odds ratio [OR] = 7.13, p = .008), difficulties falling asleep (OR = 7.33, p = .021), and frequent awakenings during the night (OR = 7.10, p = .040) in a logistic regression analysis. Conclusion: Sleep dissatisfaction is frequent among psychogeriatric outpatients. Subjects taking hypnotic drugs have more sleep-related complaints than those who do not. The clinical use of hypnotics may not be very effective for the treatment of sleep-related problems in the elderly. There is an urgent need for systematic prospective controlled studies to assess the efficacy and safety of the various forms of treatment of insomnia in old age.