Key Facts

Polypharmacy is a growing challenge driven by an ageing population and increasing multi-morbidity. While some polypharmacy is appropriate ('necessary polypharmacy'), much is problematic. Structured medication review and deprescribing can significantly reduce harm.

Epidemiology

• UK: ~30% of adults >65 take ≥5 regular medications
• ~10% of adults >65 take ≥10 regular medications
• Care home residents: average ~8 medications
• ADRs cause ~6.5% of hospital admissions; >70% are predictable and preventable
• NHS cost of ADR-related admissions: ~£500 million/year

Aetiology

• Multi-morbidity: multiple conditions each requiring treatment
• Clinical guidelines: guideline adherence for each condition individually → cumulative pill burden
• Prescribing cascade: ADR misinterpreted as new disease → additional drug
• Fragmented care: multiple prescribers without coordination
• Patient expectations: perceived need for medication for every symptom
• Failure to review: 'drug accumulation' — medications started but never stopped

Pathophysiology

• Pharmacokinetic changes in elderly: reduced renal clearance, hepatic blood flow, lean body mass, increased body fat, reduced albumin
• Pharmacodynamic changes: increased sensitivity to sedatives, anticoagulants, anticholinergics
• Drug interactions: risk increases exponentially with number of medications
• Anticholinergic burden: cumulative effect of drugs with anticholinergic properties → confusion, falls, constipation, urinary retention, dry mouth
• Serotonergic burden: multiple serotonergic drugs → serotonin syndrome risk

Recognising Problematic Polypharmacy

• Patient on ≥5 medications — trigger for structured review
• Falls: sedating drugs, postural hypotension (alpha-blockers, antihypertensives), anticholinergics
• Confusion/cognitive decline: anticholinergic burden, benzodiazepines, opioids
• GI symptoms: constipation (opioids, anticholinergics), nausea (multiple mechanisms)
• Renal impairment: NSAIDs, ACE inhibitors, diuretics ('triple whammy')
• Hypotension/syncope: multiple antihypertensives, alpha-blockers, diuretics
• Bleeding: anticoagulant + antiplatelet + NSAID

Prescribing Cascade Examples

• NSAID → hypertension → antihypertensive → postural hypotension → falls
• Metoclopramide → parkinsonian symptoms → levodopa
• Amlodipine → ankle oedema → furosemide

Red Flags

• Fall in patient on ≥4 fall-risk medications
• Acute kidney injury: 'triple whammy' (NSAID + ACE inhibitor + diuretic)
• Hospitalisation with adverse drug reaction in patient on multiple medications
• Cognitive decline in patient with high anticholinergic burden

Medication Review Tools

• STOPP criteria: Screening Tool of Older Persons' Prescriptions — identifies potentially inappropriate medications
• START criteria: Screening Tool to Alert to Right Treatment — identifies omitted beneficial medications
• Beers criteria: American Geriatrics Society — similar purpose
• Anticholinergic Burden Calculator: quantifies cumulative anticholinergic load
• MUST score: nutritional assessment (polypharmacy can affect appetite)

Bloods

• U&Es: renal function — essential for dose adjustment
• LFTs: hepatic function
• FBC: anaemia (GI bleeding from NSAIDs/anticoagulants)
• HbA1c: glycaemic control — may need adjusting after medication changes
• Bone profile, vitamin D: osteoporosis management

Special Assessments

• Falls risk assessment: if on fall-risk medications
• Cognitive assessment (AMT/MMSE): if anticholinergic burden concerns
• Lying/standing BP: if on antihypertensives — assess postural hypotension
• ECG: if on QT-prolonging drugs

Structured Medication Review (SMR)

• NICE NG5: recommends SMR at least annually for patients with polypharmacy
• Who needs SMR: ≥10 medications, care home residents, recent hospital discharge, recurrent falls, renal impairment, multiple prescribers
• Pharmacist-led: community and practice pharmacists increasingly leading SMRs

Deprescribing Process

1. Identify potentially inappropriate medications (STOPP criteria, clinical judgement)
2. Assess risk-benefit: consider life expectancy, treatment goals, patient preference
3. Plan withdrawal: taper gradually (especially beta-blockers, corticosteroids, benzodiazepines, opioids, PPIs)
4. Monitor: symptoms, bloods, falls, function after withdrawal
5. Document: rationale for changes

Key Deprescribing Targets

• PPIs: step down if >8 weeks without clear indication; try H2RA or as-needed
• Benzodiazepines/Z-drugs: taper over weeks–months; switch to diazepam equivalent then reduce
• Statins: consider stopping in frail elderly with limited life expectancy and no CVD history
• Bisphosphonates: review after 3–5 years (drug holiday may be appropriate)
• Anticholinergics: identify and reduce cumulative burden
• Antihypertensives: reduce if postural hypotension or BP target too aggressive in frail elderly

Non-Pharmacological

• Patient and carer education: explain reasons for changes; shared decision-making
• Medication aids: dosette boxes, blister packs, reminder apps
• Simplify regimens: OD dosing where possible, combination preparations

Referral Criteria

• Clinical pharmacology/pharmacy: complex polypharmacy, multiple interactions
• Geriatric medicine: frail elderly with problematic polypharmacy
• Falls clinic: polypharmacy-related falls

• Deprescribing can reduce ADRs, falls, hospitalisations, and mortality
• Structured medication reviews reduce inappropriate prescribing by ~30–40%
• Deprescribing PPIs, benzodiazepines, and antihypertensives in appropriate patients is safe and well-tolerated
• Patient satisfaction generally improves with reduced pill burden
• Pharmacist-led reviews are cost-effective and improve outcomes
• Failure to address polypharmacy: ongoing ADR risk, declining function, avoidable hospitalisations

STOPP/START Examples

Anticholinergic Burden — High-Risk Drugs