Drug usage was studied in an ambulatory geriatric population. Prescription and nonprescription drug use is described for 3,192 participants in a geriatric screening program (the Dunedin Program). Average drug use by these participants was found to be 3.2 medications. The use of both prescription and nonprescription drugs was higher for the women than for the men. In this population, drug use by both men and women increased with age, and this increase was mainly due to an increased use of prescription drugs. Participants were found to be taking numerous multiple-ingredient drug products.