Potentially Inappropriate Prescribing

Potentially inappropriate prescribing describes the use of medicines whose risk of harm in a given older patient is likely to outweigh their benefit, or the omission of medicines that would clearly help. The qualifier 'potentially' signals that the judgement is a flag for review rather than a verdict, since appropriateness depends on the individual. Explicit criteria such as the Beers Criteria and STOPP/START have been developed to help identify these medicines in older adults.

Definition

Potentially inappropriate prescribing is prescribing in which the likely risks of a medicine outweigh its likely benefits for a particular older patient, including both potentially inappropriate medications (drugs better avoided) and potential prescribing omissions (beneficial drugs not given), as flagged by explicit or implicit assessment.

Scope

The topic covers the concept of prescribing appropriateness, the distinction between explicit (criterion-based) and implicit (judgement-based) assessment tools, the major instruments used in older adults, and the idea that potentially inappropriate prescribing includes both the use of risky medicines and the under-use of beneficial ones. It is a reference treatment of how prescribing quality is assessed, not a list of drugs to avoid in practice.

Core questions

• What makes a medicine 'potentially inappropriate' for an older adult?
• How do explicit criteria differ from implicit, judgement-based assessment?
• What are the major tools used to identify inappropriate prescribing?
• Why does inappropriate prescribing include omitting beneficial medicines, not only adding risky ones?

Key concepts

• Potentially inappropriate medications (PIMs)
• Explicit (criterion-based) tools
• Implicit (judgement-based) tools
• Beers Criteria
• STOPP criteria (potentially inappropriate medications)
• START criteria (prescribing omissions)
• Prescribing appropriateness
• Risk-benefit balance
• Medication review

Mechanisms

Appropriateness tools work in two broad ways. Explicit tools are lists of drug- or condition-specific rules that can be applied with little clinical interpretation, such as the AGS Beers Criteria, which name medications generally best avoided in older adults (AGS Beers Criteria Update Expert Panel, 2023), and the STOPP component of STOPP/START, which flags potentially inappropriate medications, paired with START, which flags beneficial medicines that have been omitted (O'Mahony et al., 2014). Implicit tools instead guide a clinician through structured questions about each medicine's indication and risk-benefit balance, relying more on judgement. Both approaches aim to surface medicines whose harms may outweigh benefits, a problem closely tied to the adverse-event burden of polypharmacy (Maher, Hanlon, & Hajjar, 2013), and to direct them toward review and, where indicated, deprescribing (Scott et al., 2015).

Clinical relevance

Tools for identifying potentially inappropriate prescribing are widely used in research and quality improvement to flag medicines that warrant review in older adults. This entry explains what these tools are and how they are constructed; it is educational background and does not itself indicate that any particular medicine should be started, avoided, or stopped for an individual, which remains a clinical decision.

Epidemiology

Potentially inappropriate prescribing is common in older populations across care settings, and its measured frequency depends heavily on which tool is applied, since the criteria differ in scope and structure (O'Mahony et al., 2014; AGS Beers Criteria Update Expert Panel, 2023). It is associated with the broader burden of medication-related harm seen with polypharmacy in older adults (Maher, Hanlon, & Hajjar, 2013).

History

The first explicit criteria for inappropriate medication use in older adults were introduced by Mark Beers in the early 1990s and have since been revised and maintained by the American Geriatrics Society, most recently in the 2023 update (AGS Beers Criteria Update Expert Panel, 2023). A complementary European instrument, STOPP/START, added an explicit list of prescribing omissions alongside potentially inappropriate medications and reached its second version in 2015 (O'Mahony et al., 2014). The growth of these tools paralleled rising concern about polypharmacy and the development of deprescribing as a structured response (Scott et al., 2015).

Debates

Explicit versus implicit assessment of appropriateness

Explicit criterion-based tools are reproducible and easy to apply but cannot capture every individual circumstance, while implicit judgement-based tools are more flexible but less consistent; the field uses both, and the balance between them is a continuing methodological question.

Key figures

• Mark Beers
• Donna Fick
• Denis O'Mahony
• Paul Gallagher

Seminal works

• omahony-2014
• ags-beers-2023

Frequently asked questions

Why is it called 'potentially' inappropriate?

Because appropriateness depends on the individual patient. The criteria flag medicines that often carry more risk than benefit in older adults, signalling that they should be reviewed rather than declaring them wrong in every case.

What is the difference between the Beers Criteria and STOPP/START?

Both are explicit tools for older adults. The Beers Criteria list medications generally best avoided; STOPP/START adds START, which also flags beneficial medicines that have been omitted, so it covers both over- and under-prescribing.