The prescription of analgesics and anti-inflammatory drugs (analgesics) was studied using computerized patient records from a Finnish health centre with a population base of some 27,000 inhabitants. A random sample of every fifth patient visiting the health centre in 1986 was chosen. This study sample consisted of 4,577 patients with 17,021 physician contacts and altogether 14,035 prescriptions during the 1-year follow-up: of these analgesics comprised 14.8%. The proportion of the study population who received at least one analgesic prescription was 23 +/- 1.2% (95% CI). The use of physician contacts as a base revealed 10.7 +/- 0.5% (95% CI) of the contacts with an analgesic prescription. The exposure to analgesics among males increased with age from 17% for those aged 15-34 years to 34% for those aged 75 years or more. Among women, exposure to analgesics increased from 17% (15-34 years) to 41% (75 years or more). Most of patients who received analgesic prescriptions were incidental users (one or two analgesic prescriptions per year). Only 4% of women and 3% of men were categorized as heavy users of analgesics (seven or more analgesic prescriptions per year). The proportion of heavy users increased with age and was highest in the oldest age-group (75 years or more). In order to make informed policy judgements about drug use in society, we need routine sales statistics and patient-specific drug-use data such as those presented in this paper.