Recent patterns of medication use in the ambulatory adult population of the United States: the Slone survey.

Abstract

Data on the range of prescription and over-the-counter drug use in the United States are not available. To provide recent population-based information on use of all medications, including prescription and over-the-counter drugs, vitamins and minerals, and herbal preparations/natural supplements in the United States. Ongoing telephone survey of a random sample of the noninstitutionalized US population in the 48 continental states and the District of Columbia; data analyzed here were collected from February 1998 through December 1999. Use of medications, by type, during the preceding week, compared by demographic characteristics. Among 2590 participants aged at least 18 years, 81% used at least 1 medication in the preceding week; 50% took at least 1 prescription drug; and 7% took 5 or more. The highest overall prevalence of medication use was among women aged at least 65 years, of whom 12% took at least 10 medications and 23% took at least 5 prescription drugs. Herbals/supplements were taken by 14% of the population. Among prescription drug users, 16% also took an herbal/supplement; the rate of concurrent use was highest for fluoxetine users, at 22%. Reasons for drug use varied widely, with hypertension and headache mentioned most often (9% for each). Vitamins/minerals were frequently used for nonspecific reasons such as "health" (35%); herbals/supplements were also most commonly used for "health" (16%). In any given week, most US adults take at least 1 medication, and many take multiple agents. The substantial overlap between use of prescription medications and herbals/supplements raises concern about unintended interactions. Documentation of usage patterns can provide a basis for improving the safety of medication use.