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Overview of Drug Therapy in Older Adults


J. Mark Ruscin

, PharmD, FCCP, BCPS, Southern Illinois University Edwardsville School of Pharmacy;

Sunny A. Linnebur

, PharmD, BCPS, BCGP, University of Colorado Anschutz Medical Campus

Last full review/revision Dec 2018| Content last modified Dec 2018
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Prevalence of prescription drug use increases substantially with age. Survey data from 2010–2011 indicate that almost 90% of older adults regularly take at least 1 prescription drug, almost 80% regularly take at least 2 prescription drugs, and 36% take at least 5 prescription drugs (1). When over-the-counter and dietary supplements are included, these prevalence rates increase substantially. Women take more drugs, particularly psychoactive and arthritis drugs. Drug use is greatest among the frail older adult, hospitalized patients, and nursing home residents; a typical nursing home resident takes 7 to 8 different drugs regularly.

Providing safe, effective drug therapy for older adults is challenging for many reasons:

  • They use more drugs than any other age group, increasing risk of adverse effects and drug interactions, and making adherence more difficult.

  • They are more likely to have chronic disorders that may be worsened by the drug or affect drug response.

  • Their physiologic reserves are generally reduced and can be further reduced by acute and chronic disorders.

  • Aging can alter pharmacodynamics and pharmacokinetics of drugs.

  • They may be less able to obtain or afford drugs.

There are 2 main approaches to optimizing drug therapy in older adults:

  • Using appropriate drugs as indicated to maximize cost-effectiveness

  • Avoiding adverse drug effects

Because the risk of adverse drug effects is higher, overprescribing (polypharmacy) has been targeted as a major problem for older adults. However, underprescribing appropriate and therapeutically beneficial drugs must also be avoided. (See also Drug-Related Problems in Older Adults and Drug Categories of Concern in Older Adults.)


  • 1. Qato DM, Wilder J, Schumm LP, et al: Changes in prescription and over-the-counter medication and dietary supplement use among older adults in the United States, 2005 vs 2011. JAMA Intern Med 176(4):473-82, 2016. doi: 10.1001/jamainternmed.2015.8581.

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