Use of prescribed medications in a South Australian community sample

To determine the extent of self-reported use of prescription medications in an Australian community sample.

Face-to-face interviews with a random, representative sample of the South Australian population (aged > or = 15 years) living in metropolitan and rural areas. The study, a Health Omnibus Survey, was conducted between March and June 2004.

Reported number of prescribed medications used per person, most common categories of medication, and use by individuals of multiple medications for the same body system.

From 4700 households selected, 3015 participants were interviewed (65.9% response rate). Of respondents, 46.8% were using prescribed medications; 171 respondents (5.7%) were taking six or more medications, and four were taking 16 or more; 23.2% were using medications for the cardiovascular system, with 11.9% using agents acting on the renin-angiotensin system. Prescription medication use increased with age, with over 10% of respondents aged > or = 55 years using six or more medications.

Use of multiple prescribed medications was common, with the potential for significant drug interactions. Assuming a similar pattern of medication use Australia-wide, reducing the number of prescribed medications by one for people taking six or more medications would save the federal government about 380 million dollars a year.