This cross-sectional analysis of a population-based cohort investigates the postural changes in blood pressure (BP) and heart rate and assesses the prevalence of orthostatic hypotension (OH) and its associations with the medicines used by an elderly population. The study population (n=1000) was a random sample of persons aged 75 years or older in the City of Kuopio, Finland. In 2004, altogether, 781 persons participated in the study. After the exclusion of persons living in institutional care (n=82) and those without orthostatic test (n=46), the final study population comprised 653 home-dwelling elderly persons. OH was defined as a > or =20 mm Hg drop of systolic BP or a > or =10 mm Hg drop of diastolic BP or both 1 or 3 min after standing up from supine position. Systolic BP dropped for more than half of the home-dwelling elderly when they stood up from a supine to a standing position. The total prevalence of OH was 34% (n=220). No significant gender or age differences were seen. The prevalence of OH was related to the total number of medicines in regular use (P<0.05). OH and postural changes in BP are more common among the home-dwelling elderly than reported in previous studies. The prevalence of OH is related to the number of medicines in regular use. There is an obvious need to measure orthostatic BP of elderly persons, as low BP and OH are important risk factors especially among the frail elderly persons.