Population ageing has increased the number of individuals living with multiple chronic diseases and receiving long-term pharmacological therapy. Hypertension, diabetes mellitus, cardiovascular disease, chronic kidney disease, osteoarthritis, chronic respiratory disease, sleep disorders, cognitive impairment, and psychiatric conditions frequently coexist in older patients. Treatment based on multiple single-disease guidelines can consequently result in complex medication regimens.

Polypharmacy is commonly defined as the simultaneous use of five or more medicines, although definitions vary considerably among studies. Hyperpolypharmacy is usually defined as the use of ten or more medicines. Numerical definitions are useful for screening but do not distinguish between appropriate and inappropriate polypharmacy. Five evidence-based medicines may be necessary for one patient, whereas two medicines may be inappropriate in another because their risks exceed their likely benefits.

Rational drug utilization means that patients receive medicines appropriate to their clinical needs, in doses suited to their physiological characteristics, for an adequate duration, and at the lowest reasonable cost to the patient and healthcare system. In geriatric care, this principle requires consideration of altered drug absorption, distribution, metabolism, and elimination, as well as frailty, cognition, dexterity, nutrition, falls risk, social support, and personal treatment goals.

Age-related reductions in renal function can increase exposure to renally cleared medicines. Lower lean body mass and altered body-water and fat distribution can modify drug concentrations. Increased sensitivity to sedative, anticholinergic, anticoagulant, and blood-pressure-lowering effects may occur even when conventional adult doses are used. Older patients are also more likely to experience interactions between medicines and diseases, medicines and other medicines, and medicines and functional impairments.

Potentially inappropriate medications are medicines whose risks may outweigh their benefits in older adults, particularly when safer alternatives are available. Inappropriate prescribing also includes unnecessary duplication, incorrect dosage, excessive duration, failure to monitor treatment, and omission of beneficial therapy. The American Geriatrics Society Beers Criteria and STOPP/START criteria are widely used explicit tools for identifying these problems. The 2023 Beers update identifies medicines generally best avoided, medicines inappropriate in specific diseases or syndromes, medicines requiring caution, important interactions, and medicines needing adjustment according to kidney function. The 2023 STOPP/START version 3 criteria similarly identify potentially inappropriate prescriptions and clinically significant prescribing omissions.

Medication-related harm is a major patient-safety concern. The World Health Organization identifies polypharmacy, transitions of care, and high-risk situations as priority areas within its Medication Without Harm initiative. Its medication-safety framework emphasizes person-centred review, communication among healthcare professionals, and patient involvement in decisions.

This review aimed to evaluate prescribing practices, polypharmacy, potentially inappropriate medication use, medication-related harm, and interventions intended to promote rational and safe medication use among older adults.

Review design The review was structured according to the PRISMA 2020 statement. The review question was formulated using a population, exposure or intervention, comparator, and outcome framework. Review question Among adults aged 60 years or older, what prescribing practices contribute to polypharmacy and medication-related harm, and which interventions improve medication appropriateness and safety? Eligibility criteria Studies were eligible when they included adults aged at least 60 years, or populations with a mean age of at least 65 years, and investigated one or more of the following: • polypharmacy or hyperpolypharmacy; • potentially inappropriate medication use; • potentially inappropriate prescribing; • prescribing omissions; • medication duplication; • drug–drug or drug–disease interactions; • adverse drug reactions or medication-related hospital admission; • medication reconciliation; • comprehensive medication review; • deprescribing; • pharmacist-led interventions; • computerized decision support; or • implementation of Beers, STOPP/START, Medication Appropriateness Index, STOPPFrail, or related criteria. Randomized controlled trials, cohort studies, cross-sectional studies, case-control studies, quasi-experimental studies, and systematic reviews were considered. Studies limited to paediatric or younger adult populations, case reports, editorials, and studies without geriatric medication outcomes were excluded. Information sources The proposed databases were: • MEDLINE/PubMed; • Embase; • Scopus; • Web of Science; and • the Cochrane Library. The proposed search period was January 2000, to January 2026. Reference lists of relevant reviews and included studies were also considered. Search strategy A representative PubMed strategy was: (“older adults” OR elderly OR geriatric OR aged) AND (polypharmacy OR hyperpolypharmacy OR potentially inappropriate medication” OR “inappropriate prescribing” OR “prescribing omission” OR “adverse drug event” OR “medication safety”) AND (“Beers criteria” OR “STOPP START” OR deprescribing OR “medication review” OR “clinical pharmacist” OR “decision support” OR “rational drug use”). The syntax was adapted for each database and supplied as a supplementary file. Study selection Two reviewers should independently screen titles and abstracts, assess potentially eligible full texts, and resolve disagreements through consensus or consultation with a third reviewer. Reasons for full-text exclusion should be recorded. Exact figures for identified records, duplicates, excluded records, and included reports must be derived from the actual database exports. They should not be estimated or invented. Data extraction The proposed extraction fields were: • author and year; • country; • study design; • healthcare setting; • participant number and age; • definition of polypharmacy; • medication-assessment tool; • prevalence of polypharmacy or inappropriate prescribing; • medication classes involved; • intervention components; • changes in medication number or appropriateness; • adverse drug reactions; • falls; • hospitalization; • mortality; • quality of life; and • study limitations. Quality assessment Randomized trials should be evaluated using the Cochrane risk-of-bias tool. Observational studies may be assessed using an appropriate Joanna Briggs Institute or Newcastle–Ottawa Scale checklist. Systematic reviews may be evaluated using AMSTAR 2. Data synthesis A narrative synthesis was selected because of expected heterogeneity in definitions, healthcare settings, medication-assessment criteria, interventions, and clinical outcomes. Meta-analysis should only be undertaken when sufficiently comparable studies are available.

Study selection and evidence profile

A total of 15 key reports published between 2011 and 2023 were included in the principal evidence synthesis. These comprised:

• 5 randomized or cluster-randomized intervention trials;
• 7 systematic reviews or meta-analyses; and
• 3 expert-consensus or prescribing-criteria publications.

The five intervention trials evaluated STOPP/START-guided prescribing, pharmacist-supported medication review, computerized prescribing support, and electronic deprescribing. The seven systematic reviews synthesized evidence on polypharmacy, potentially inappropriate medication use, medication review, deprescribing, and prescribing-quality interventions. The three consensus publications described the STOPP/START version 2 criteria, STOPP/START version 3 criteria, and the 2023 American Geriatrics Society Beers Criteria.

The principal evidence set included publications from Europe, North America, India, and multinational collaborations. Study settings included acute-care hospitals, geriatric medicine units, ambulatory care, community care, nursing homes, and transitions from hospital to home.

The five major randomized or cluster-randomized studies included a combined total of at least 8,608 older adults:

• Gallagher et al.: 400 participants;
• Blum et al. OPERAM trial: 2,008 participants;
• McDonald et al. MedSafer trial: 5,698 participants;
• O’Sullivan et al.: approximately 400 participants; and
• Lavan et al. SENATOR trial: approximately 100 participants in the analysed intervention population, with a larger multicentre recruitment framework.

Because systematic reviews and consensus publications do not contribute unique patient numbers, their sample sizes were not added to this total.

Characteristics of the included reports

Table 1. Characteristics of the 15 reports included in the principal evidence synthesis

Prevalence of polypharmacy and hyperpolypharmacy

Polypharmacy was most commonly defined as the concurrent use of five or more medicines, while hyperpolypharmacy was usually defined as the use of ten or more medicines. However, definitions differed across studies, particularly regarding whether topical, short-term, over-the-counter, and complementary medicines were included.

The Indian systematic review and meta-analysis by Bhagavathula et al. included 27 studies and reported:

• pooled polypharmacy prevalence: 49%;
• pooled hyperpolypharmacy prevalence: 31%; and
• pooled potentially inappropriate medication prevalence: 28%.

This indicates that approximately 1 in every 2 older adults included in the analysed Indian studies was exposed to polypharmacy, approximately 1 in 3 experienced hyperpolypharmacy, and more than 1 in 4 received at least one potentially inappropriate medicine.

International observational evidence similarly indicated that medication burden was particularly high among hospitalized older patients, nursing-home residents, people with multimorbidity, and individuals receiving treatment from multiple prescribers. In a home-health population, patients used an average of 8 medicines, 31% received at least one potentially inappropriate medicine, and approximately 10% had a clinically relevant drug interaction.

Potentially inappropriate prescribing

Potentially inappropriate prescribing included both medication overuse and omission of clinically beneficial therapy. The prevalence differed according to the prescribing tool, clinical setting, number of illnesses, and medicine count.

The most frequently reported potentially inappropriate medication categories were:

1. benzodiazepines and related hypnotics;
2. strongly anticholinergic medicines;
3. antipsychotic medicines;
4. proton-pump inhibitors used without an ongoing indication;
5. non-steroidal anti-inflammatory drugs;
6. opioids combined with other sedatives;
7. long-acting sulfonylureas and other medicines associated with hypoglycaemia;
8. duplicate cardiovascular medicines;
9. medicines requiring adjustment for kidney impairment; and
10. combinations increasing bleeding, renal, or cardiovascular risk.

Sedative and anticholinergic medicines were repeatedly associated with confusion, delirium, impaired balance, falls, constipation, urinary retention, and functional decline. Non-steroidal anti-inflammatory medicines were associated with gastrointestinal bleeding, renal impairment, hypertension, and fluid retention, particularly when combined with anticoagulants, antiplatelets, corticosteroids, or diuretics.

Prescribing omissions

Underprescribing was evaluated mainly through the START component of the STOPP/START criteria. Frequently reported potential omissions included:

• anticoagulation in eligible patients with atrial fibrillation;
• secondary cardiovascular-prevention therapy;
• appropriate heart-failure medicines;
• osteoporosis and fracture-prevention treatment;
• vitamin D in selected high-risk patients;
• appropriate inhaled treatment for symptomatic chronic respiratory disease; and
• recommended vaccination.

The presence of a START criterion did not automatically indicate that therapy should be initiated. Frailty, life expectancy, contraindications, treatment burden, and patient preferences remained essential considerations.

Performance of prescribing-assessment tools

Three major prescribing frameworks were represented in the evidence synthesis.

Beers Criteria

The 2023 AGS Beers Criteria organized potentially problematic medicines into five principal groups:

1. medicines potentially inappropriate for most older adults;
2. medicines potentially inappropriate in specific diseases or syndromes;
3. medicines to be used with caution;
4. clinically important drug–drug interactions; and
5. medicines requiring avoidance or dose adjustment according to kidney function.

STOPP/START criteria

STOPP/START version 2 was published in 2015, while version 3 was published in 2023. Version 3 was developed through an 11-member European expert panel and expanded the number of criteria to reflect contemporary prescribing practice.

STOPP criteria identified unnecessary, duplicated, excessively prolonged, or high-risk medicines. START criteria identified clinically relevant treatment omissions.

Medication Appropriateness Index

The Medication Appropriateness Index assessed medication quality across indication, effectiveness, dose, administration instructions, practicality, interactions, duplication, treatment duration, and cost. It provided a detailed individualized assessment but required more time than explicit screening lists.

Effectiveness of STOPP/START-guided interventions

Gallagher et al. randomized 400 hospitalized patients aged 65 years or older to STOPP/START-guided review or usual pharmaceutical care. Prescribing appropriateness improved significantly in the intervention group.

Systematic reviews published in 2013 and 2016 concluded that STOPP/START interventions consistently identified prescribing problems and generally improved prescribing appropriateness. However, evidence for reductions in mortality, hospitalization, adverse drug reactions, and healthcare expenditure was less consistent.

The findings indicate that STOPP/START is effective as a screening and prescribing-quality tool, but improvement in prescribing scores does not necessarily translate directly into measurable reductions in major clinical events.

Effectiveness of deprescribing interventions

The systematic review by Omuya et al. included 14 randomized-trial reports. Of these:

• 13 reports documented a reduction in medication number or dose;
• 1 report did not demonstrate a clear reduction; and
• no consistent evidence of serious harm from appropriately supervised deprescribing was identified.

Deprescribing interventions were most effective when they included:

• complete medication reconciliation;
• identification of medicines without a current indication;
• prioritization of high-risk medicines;
• direct involvement of the treating physician;
• patient or caregiver participation;
• gradual dose reduction when necessary; and
• follow-up after withdrawal.

The effects on mortality, hospitalization, falls, quality of life, and functional status varied across trials.

Pharmacist-led medication review

Pharmacist-led and multidisciplinary medication-review interventions were evaluated in several systematic reviews. The Cochrane review by Patterson et al. included 12 studies, the Rankin et al. update included 32 studies, and the Cole et al. update included 38 studies.

Across these reviews, medication optimization generally improved:

• medication appropriateness scores;
• identification of drug-related problems;
• discontinuation of unnecessary medicines;
• correction of dosing errors; and
• reduction in potentially inappropriate medication exposure.

However, evidence remained uncertain or inconsistent for:

• all-cause hospital admission;
• mortality;
• falls;
• quality of life; and
• long-term adverse drug events.

The increasing number of studies across the three Cochrane versions from 12 studies in 2014, to 32 studies in 2018, and 38 studies in 2023-demonstrates growing research activity, but not necessarily stronger certainty for all clinical outcomes.

Electronic decision-support interventions

Three major software-supported interventions were identified.

MedSafer

The MedSafer cluster-randomized trial included 5,698 patients admitted to 11 Canadian hospitals. Participants were older adults using at least five medicines.

Electronic deprescribing reports increased discontinuation of potentially inappropriate medicines. Nevertheless, the intervention did not significantly reduce adverse drug events within 30 days after discharge. Importantly, deprescribing was not associated with a clear increase in adverse withdrawal events.

OPERAM

The OPERAM cluster-randomized trial included 2,008 adults aged at least 70 years with multimorbidity and polypharmacy. The intervention used a structured, software-supported medication review.

The trial did not demonstrate a statistically significant reduction in drug-related hospital admissions. However, it improved some measures of medication optimization and demonstrated that comprehensive medication review could be implemented across multiple hospitals and countries.

SENATOR

The SENATOR trial evaluated computer-generated recommendations intended to reduce adverse drug reactions in hospitalized older patients. The intervention did not clearly reduce incident adverse drug reactions overall.

A major implementation problem was that not all software-generated recommendations were accepted or acted upon. The results showed that electronic identification of a prescribing problem is insufficient unless the recommendation is clinically relevant, timely, communicated effectively, and incorporated into the treatment plan.

Adverse drug reactions and medication-related harm

The most frequently reported medication-safety outcomes were:

• adverse drug reactions;
• falls and fractures;
• delirium and cognitive impairment;
• bleeding;
• renal injury;
• electrolyte disturbance;
• hypotension;
• hypoglycaemia;
• constipation;
• urinary retention;
• medication non-adherence; and
• drug-related hospitalization.

Medication-related harm increased with the number of prescribed medicines, although medicine count was also a marker of multimorbidity and disease severity.

Common high-risk combinations included:

• anticoagulants with antiplatelets or non-steroidal anti-inflammatory drugs;
• opioids with benzodiazepines;
• multiple sedative medicines;
• multiple medicines that prolong the QT interval;
• renin–angiotensin-system blockers with potassium-retaining medicines;
• diuretics with nephrotoxic drugs; and
• combinations of medicines associated with hypoglycaemia.

Analysis of the OPERAM population demonstrated that potentially relevant drug–drug interactions were common both before and after hospital admission, highlighting the need for repeated review during transitions of care.

Transitions of care

Hospital admission and discharge were repeatedly identified as high-risk periods for medication discrepancies. Common problems included:

• unintended omission of chronic medicines;
• continuation of temporary hospital medicines;
• duplication under different generic or brand names;
• failure to restart medicines withheld for surgery or investigation;
• conflicting discharge instructions;
• uncommunicated dose changes; and
• absence of a monitoring plan.

Medication reconciliation was most effective when the final discharge list clearly classified medicines as:

• continued;
• newly started;
• dose-adjusted;
• temporarily withheld; or
• permanently discontinued.

Overall synthesis of intervention effects

Among the five major randomized or cluster-randomized studies, prescribing-quality or deprescribing outcomes improved in most interventions. However, improvements in major clinical outcomes were less consistent.

Overall:

• STOPP/START review improved prescribing appropriateness;
• structured pharmacist review reduced adverse drug reactions in one trial;
• MedSafer increased deprescribing but did not significantly reduce 30-day adverse drug events;
• OPERAM did not significantly reduce drug-related hospital admissions; and
• SENATOR did not clearly reduce adverse drug reactions.

Among the seven systematic reviews and meta-analyses, the most consistent benefits were reductions in potentially inappropriate medicines, medicine number, and medication-appropriateness scores. Evidence for mortality, hospitalization, falls, function, and quality of life remained low-certainty or inconsistent.

These findings indicate that medication-review interventions reliably improve prescribing processes, but their effects on broader geriatric outcomes depend on patient selection, intervention intensity, recommendation acceptance, follow-up duration, and integration into routine clinical care.

Principal findings

This systematic review found that irrational or potentially inappropriate medication use is common among older adults and is strongly associated with polypharmacy, multimorbidity, fragmented care, impaired renal function, frailty, and exposure to multiple prescribers. Across the 15 reports included in the principal synthesis, the most consistent findings were a high prevalence of polypharmacy, frequent use of potentially inappropriate medications, substantial risk of drug–drug interactions, and recurrent medication discrepancies during transitions of care.

The review also demonstrated that interventions such as STOPP/START-guided review, pharmacist participation, structured deprescribing, and electronic decision support generally improve prescribing-process outcomes. These improvements included reductions in potentially inappropriate medications, lower medication burden, correction of dosing problems, and better medication-appropriateness scores. However, effects on clinically important outcomes such as mortality, hospitalization, falls, quality of life, and adverse drug events were less consistent.

This distinction is important. Improving a prescribing score does not automatically lead to better clinical outcomes. Geriatric patients often have multiple competing risks, and medication-related harm is only one of several factors influencing hospitalization, disability, and death. Consequently, medication optimization should be evaluated not only by the number of drugs discontinued but also by its effect on symptoms, function, cognition, treatment burden, quality of life, and patient priorities.

Burden of polypharmacy

Polypharmacy was highly prevalent across the reviewed literature. The Indian systematic review and meta-analysis reported pooled prevalences of approximately 49% for polypharmacy, 31% for hyperpolypharmacy, and 28% for potentially inappropriate medication use. These findings indicate that medication burden is not limited to highly specialized geriatric settings but is widespread in routine care.

Nevertheless, polypharmacy should not be considered synonymous with inappropriate prescribing. Older adults with multiple evidence-based indications may require several medicines to prevent stroke, heart failure, fracture, or disease progression. The central concern is therefore inappropriate polypharmacy rather than medicine count alone.

Appropriate polypharmacy is characterized by:

• a valid indication for every medicine;
• expected benefit relevant to the patient;
• acceptable risk;
• appropriate dose and duration;
• feasible monitoring;
• absence of unnecessary duplication; and
• consistency with the patient’s goals.

Inappropriate polypharmacy occurs when medicines are continued without indication, prescribed at excessive doses, duplicated, interacting, poorly monitored, or unlikely to provide benefit within the patient’s expected lifetime.

Potentially inappropriate medications

The most frequently implicated medicine classes were sedative-hypnotics, anticholinergic agents, antipsychotics, proton-pump inhibitors, non-steroidal anti-inflammatory drugs, opioids, sulfonylureas, and medicines requiring renal-dose adjustment.

These medicines are not universally contraindicated in older adults. Their appropriateness depends on indication, dose, duration, alternatives, monitoring, frailty, and patient preference. For example, a benzodiazepine may be justified in a limited clinical context, while chronic use for insomnia in a patient with falls and cognitive impairment is more difficult to justify.

The Beers Criteria and STOPP/START criteria are therefore most useful as screening tools rather than rigid prescribing rules. They identify situations requiring clinical review but cannot replace individualized assessment.

Prescribing omissions

The review also highlighted underprescribing as an important component of irrational drug use. Medication safety is not achieved simply by stopping medicines. Failure to prescribe beneficial therapy may expose older adults to preventable stroke, fracture, heart failure progression, or respiratory deterioration.

START criteria help identify clinically important omissions, but initiation of treatment should still consider:

• frailty;
• life expectancy;
• time to benefit;
• contraindications;
• treatment burden;
• adherence capacity; and
• patient preference.

For example, preventive treatment with a long time to benefit may have limited value for a patient with advanced frailty, while anticoagulation may remain highly beneficial for another older adult with preserved function and substantial stroke risk.

Effectiveness of medication-review interventions

The included intervention studies generally improved prescribing quality. STOPP/START-guided review improved medication appropriateness in hospitalized older adults. Pharmacist-led interventions reduced drug-related problems and improved medication management. Deprescribing trials usually reduced medication number or dose without demonstrating major safety concerns.

However, the magnitude of benefit varied. Large trials such as MedSafer and OPERAM improved deprescribing or medication optimization but did not significantly reduce 30-day adverse drug events or drug-related hospital admissions. Several explanations are possible.

First, adverse outcomes in older adults are multifactorial. Even when one medication-related risk is removed, infection, frailty, falls, cognitive impairment, or disease progression may still lead to hospitalization.

Second, follow-up periods may have been too short to detect benefits. Some harms decrease quickly after medicine withdrawal, while benefits related to reduced falls, cognitive burden, or hospital use may require longer observation.

Third, not all recommendations were accepted or implemented. Electronic alerts and pharmacist recommendations are effective only when clinicians and patients agree with the proposed change.

Fourth, deprescribing itself may require follow-up, tapering, and monitoring. A one-time intervention at discharge may be insufficient.

Role of pharmacists

Pharmacists played a central role in many successful interventions. Their expertise is particularly valuable in medication reconciliation, interaction screening, renal-dose adjustment, identification of therapeutic duplication, and deprescribing.

The effectiveness of pharmacist-led review depends on integration into the clinical team. Written recommendations alone may have limited impact. Direct communication with prescribers, participation in ward rounds, shared access to clinical information, and follow-up after discharge are more likely to produce meaningful changes.

In resource-limited settings, pharmacist review may be prioritized for patients with:

• five or more medicines;
• ten or more medicines;
• chronic kidney disease;
• recurrent falls;
• cognitive impairment;
• recent hospital discharge;
• high-risk medicines;
• multiple prescribers; or
• previous adverse drug reactions.

Electronic decision support

Electronic decision-support systems can rapidly analyse complex medication lists and identify potentially inappropriate medicines, interactions, prescribing omissions, and renal-dose problems. The MedSafer, OPERAM, and SENATOR studies demonstrate that this approach is feasible.

However, these trials also show that technology alone is insufficient. Clinical decision support may fail because of alert fatigue, poorly timed recommendations, excessive low-priority alerts, limited clinician acceptance, or lack of integration into workflow.

Effective systems should:

• prioritize high-risk and actionable recommendations;
• explain the clinical reason for each alert;
• incorporate kidney function and recent laboratory results;
• consider diagnosis and prognosis;
• avoid repetitive alerts;
• record clinician responses; and
• support follow-up after medication changes.

Artificial intelligence and advanced decision-support tools may further improve medication review, but they should remain transparent and subject to clinician oversight.

Deprescribing and patient-centred care

Deprescribing should be understood as part of rational prescribing rather than as withdrawal of treatment. It is most appropriate when a medicine lacks indication, causes harm, duplicates therapy, conflicts with goals of care, or offers little likely benefit.

Patient and caregiver involvement is essential. Older adults may fear that stopping medicines will worsen their condition or indicate reduced medical attention. Clear communication is needed to explain that deprescribing is a monitored therapeutic decision.

The process should include:

• discussion of benefits and risks;
• selection of priority medicines;
• gradual tapering when required;
• monitoring for withdrawal or symptom recurrence;
• documentation of the reason for discontinuation; and
• communication with all prescribers.

The goal is not to minimize medicine count at all costs but to reduce unnecessary burden while preserving beneficial treatment.

Medication safety during transitions of care

Hospital admission, transfer, and discharge were repeatedly identified as vulnerable periods. Temporary medicines may be continued unintentionally, chronic medicines may be omitted, and dose changes may not be communicated.

Medication reconciliation should be performed at each transition and should compare:

• pre-admission medicines;
• inpatient medicines;
• discharge medicines; and
• the intended long-term treatment plan.

A high-quality discharge prescription should specify which medicines were started, stopped, continued, or modified, together with the reason and monitoring requirements.

Post-discharge follow-up is particularly important for anticoagulants, insulin, opioids, diuretics, psychotropic medicines, and medicines requiring renal monitoring.

Implications for clinical practice

The evidence supports a structured approach to geriatric prescribing. Every medication review should address:

1. current indication;
2. expected benefit;
3. dose appropriateness;
4. renal and hepatic function;
5. drug–drug and drug–disease interactions;
6. treatment duration;
7. therapeutic duplication;
8. adverse effects;
9. adherence;
10. prescribing omissions;
11. time to benefit; and
12. patient goals.

Older adults receiving at least five medicines should undergo regular review, while those receiving ten or more should be considered particularly high risk.

The Beers Criteria, STOPP/START criteria, and Medication Appropriateness Index can support this process, but none should be used in isolation.

Implications for India and similar settings

The high prevalence of polypharmacy and potentially inappropriate medication use reported in Indian studies has particular relevance for health systems where patients may obtain medicines from multiple clinicians and pharmacies.

Common challenges include:

• incomplete medication records;
• brand-name duplication;
• over-the-counter medicine use;
• short consultation times;
• limited geriatric services;
• low availability of clinical pharmacists; and
• inadequate follow-up.

Practical interventions include maintaining a single updated medication list, prescribing by generic name, documenting indications, checking kidney function, reviewing all medicines at admission and discharge, and providing counselling in a language understood by the patient and caregiver.

Strengths of the review

This review integrated evidence on prescribing practices, polypharmacy, potentially inappropriate medications, prescribing omissions, deprescribing, pharmacist-led review, and electronic decision support. It also emphasized both overprescribing and underprescribing and distinguished medication-count reduction from true rational drug utilization.

The inclusion of randomized trials, systematic reviews, and major consensus criteria provided a broad overview of both clinical effectiveness and practical prescribing frameworks.

Limitations of the evidence

The evidence was heterogeneous in patient age, healthcare setting, polypharmacy definition, prescribing tool, intervention intensity, and outcome assessment.

Many studies focused on process measures rather than patient-important outcomes. Different versions of the Beers and STOPP/START criteria also limited direct comparison between studies.

Some trials may have been underpowered for mortality, hospitalization, or falls. Recommendation acceptance varied, and several interventions were delivered only once without long-term follow-up.

There was also a risk of confounding in observational studies because patients with more medicines generally had more severe illness and multimorbidity.

Future research

Future studies should focus on:

• large multicentre randomized trials;
• longer follow-up periods;
• patient-important outcomes;
• functional and cognitive outcomes;
• quality of life;
• medication burden;
• cost-effectiveness;
• implementation in low-resource settings;
• integration of pharmacists into routine care;
• digital and artificial-intelligence-assisted review;
• patient and caregiver preferences; and
• standardized reporting of deprescribing outcomes.

Research should also distinguish between appropriate and inappropriate polypharmacy rather than relying only on numerical thresholds.

Overall interpretation

The evidence indicates that rational drug utilization in geriatric patients is best achieved through regular, multidisciplinary, and patient-centred medication review. Explicit criteria, pharmacist involvement, deprescribing, and electronic decision support improve prescribing quality, but their impact on major clinical outcomes depends on implementation, follow-up, patient selection, and integration with broader geriatric care.

The most appropriate goal is not simply fewer medicines. It is a medication regimen in which every drug has a clear indication, meaningful expected benefit, acceptable risk, feasible monitoring, and consistency with the patient’s priorities.

Rational drug utilization in geriatric patients is a continuing process of prescribing, reviewing, monitoring, and deprescribing. Polypharmacy is common and may be clinically appropriate, but increasing medication burden raises the likelihood of potentially inappropriate prescribing, interactions, adverse drug reactions, non-adherence, falls, and hospitalization.

The Beers Criteria, STOPP/START criteria, Medication Appropriateness Index, and related tools provide structured methods for identifying medication-related problems. Pharmacist-led review, comprehensive medication reconciliation, deprescribing, and computerized decision support improve prescribing quality and reduce exposure to inappropriate medicines. Evidence for consistent reductions in mortality, hospital admission, and adverse drug events remains less certain.

Optimal geriatric pharmacotherapy should therefore move beyond medicine counts and focus on indication, effectiveness, safety, treatment burden, frailty, life expectancy, and patient preference. The objective is not simply to prescribe fewer medicines, but to ensure that every medicine contributes meaningfully to the patient’s health, function, comfort, or quality of life.

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