The prevalence of psychotropic medication consumption was assessed in the UK by surveying a representative sample of 4972 non-institutionalized individuals 15 years of age or older (participation rate, 79.6%). A questionnaire was administered over the telephone with the help of the Sleep-Eval Expert System. Topics covered included: type and name of medication, indication, dosage, duration of intake, and medical specialty of prescriber. Also collected were data pertaining to sociodemographics, physical illnesses, and DSM-IV mental disorders. Overall, 3.5% [95% CI: 3-4] of the sample reported current use of psychotropic medication. Consumption was higher among women [4.6% (3.8-5.4)] than men [2.3% (1.7-2.9)], and among the elderly (> or = 65 years of age). The distribution of psychotropics was: hypnotics 1.5%, antidepressants 1.1%, and anxiolytics 0.8%. The median duration of psychotropic intake was 52 weeks. General practitioners were the most common prescribers of psychotropics (over 80% for each class of drug). Nearly half the antidepressant users were diagnosed by the system with a DSM-IV anxiety disorder, and one-fifth the anxiolytic users with a depressive disorder. A marked improvement in sleep quality was reported by half the subjects using a psychotropic for sleep-enhancing purposes. Psychotropic users were more likely than non-users to report episodes of memory loss, vertigo, or anomia. Psychotropic medication consumption is lower and patterns of psychotropic prescription differ in the UK compared with other European and North American countries. Results suggest that physicians may not be sufficiently trained to deal with the overlap between general practice and psychiatry.