Medication use characteristics in the elderly: the Iowa 65+ Rural Health Study.

Medication use was studied in a rural, elderly population. Household interviews were conducted of 3,467 individuals aged 65 years or older. A total of 9,955 prescription or nonprescription drugs were reported by the respondents. The overall mean number of drugs per respondent was 2.87, while 12% of all respondents were not taking any drugs. Mean prescription and overall drug use increased significantly with increasing age (P less than .001), while mean nonprescription drug use was relatively constant across age groups. Significantly more women were prescription and nonprescription drug users. Directions for scheduled daily dosing accounted for 75% of all directions. The majority of prescription and nonprescription drugs had been taken on the previous day. General practitioners accounted for more prescription drugs (39.7%) than any other medical specialty. The most frequently stated purpose was cardiovascular for prescription drugs and musculoskeletal for nonprescription drugs. The three most frequent prescription drug therapeutic categories were cardiovascular (54.7%), central nervous system (CNS) agents (11.4%), and analgesics (9.4%). For nonprescription drugs, the three most frequent therapeutic categories were analgesics (39.6%), vitamins and minerals (32.9%), and laxatives (14.1%). Implications of these findings are discussed.