SP Lecture 3: Pharm & Vaccines

In geriatrics, what question should every new symptom prompt?

Could this be medication-related?

Are most adverse drug events (ADEs) in older adults preventable?

Yes — many ADEs are preventable

What percentage of US adults ≥65 used prescription medication in 2021-2022?

88.6%

Besides prescriptions, what adds to medication burden in older adults?

OTC drugs and supplements

What increases medication burden in older adults? (select all that apply)

1. Multimorbidity 2. Transitions of care

What is the common definition of polypharmacy?

Use of ≥5 medications

Which products count toward polypharmacy? (select all that apply)

1. Prescription 2. OTC 3. Complementary products

Is polypharmacy inherently inappropriate?

No — risk depends on context

Why does polypharmacy happen? (select all that apply)

1. Multimorbidity (≥2 chronic conditions) 2. Multiple prescribers and fragmented care 3. Guideline stacking (single-disease focus) 4. Prescribing cascades 5. Transitions of care (hospital → SNF → home) 6. Unreported OTC and supplement use

What is 'guideline stacking'?

Following single-disease-focused guidelines for each condition, adding up medications

What adverse outcomes are associated with polypharmacy? (select all that apply)

1. Increased ADRs and ADEs 2. Higher rates of falls, fractures, and functional decline 3. Delirium and cognitive impairment 4. Medication nonadherence and prescribing errors 5. Hospitalization, morbidity, and mortality

In a regimen, what risk do sedatives add?

Falls and sedation

In a regimen, what risk do anticholinergics add?

Confusion

In a regimen, what risk do complex schedules add?

Dosing errors

How should drug count be used clinically?

As a signal for a clinical medication review

Why may standard adult dosing be unsafe in older adults?

Age-related physiologic changes alter drug handling (PK) and response (PD)

What are the four components of pharmacokinetics?

Absorption, distribution, metabolism, excretion (ADME)

Which pharmacokinetic component is most consistently affected by aging?

Renal clearance (excretion)

How is drug absorption affected by aging overall?

Generally preserved — most medications have no clinically significant change

What age-related changes can affect absorption? (select all that apply)

1. Higher gastric pH in some patients 2. Slower gastric emptying

PPIs affect absorption of which nutrients? (select all that apply)

1. Calcium 2. Iron 3. Vitamin B12

How can slower gastric emptying affect drug effect?

Onset may be delayed; effects vary by drug

What body composition changes with aging alter drug distribution? (select all that apply)

1. Decreased total body water 2. Decreased lean body mass 3. Increased body fat 4. Low albumin with malnutrition or acute illness

Distribution changes alter which three drug parameters?

Volume of distribution, half-life, and free drug levels

What happens to hydrophilic drug levels in older adults?

Higher concentration

Which hydrophilic drugs reach higher concentrations in older adults? (select all that apply)

1. Digoxin 2. Lithium 3. Aminoglycosides

What happens to lipophilic drugs in older adults?

Prolonged half-life

Which lipophilic drugs have a prolonged half-life in older adults? (select all that apply)

1. Benzodiazepines 2. Antipsychotics 3. TCAs

What does low albumin do to highly protein-bound drugs?

Increases the free drug fraction

Which drugs have a higher free fraction with low albumin? (select all that apply)

1. Warfarin 2. Phenytoin

What hepatic changes occur with aging? (select all that apply)

1. Decreased hepatic mass 2. Decreased hepatic blood flow

How does aging affect phase I hepatic metabolism?

May decline (drug-dependent)

How does aging affect phase II hepatic metabolism?

Generally preserved

Do normal LFTs guarantee normal drug metabolism in older adults?

No

What happens to high-first-pass drugs in older adults?

Higher bioavailability

Which drugs are examples of altered hepatic metabolism in older adults (prolonged half-life/accumulation/higher bioavailability)? (select all that apply)

1. Benzodiazepines 2. Opioids 3. Beta-blockers 4. TCAs

What renal changes occur with aging? (select all that apply)

1. Decreased renal blood flow 2. Decreased GFR

Why can serum creatinine look normal in an older adult with reduced renal function?

Decreased muscle mass — serum creatinine may appear normal despite reduced renal function

What does reduced renal clearance lead to?

Drug accumulation and toxicity

Which drugs are key renal-excretion examples in older adults? (select all that apply)

1. Digoxin 2. Lithium 3. Metformin 4. Aminoglycosides 5. DOACs 6. Gabapentin

Is serum creatinine alone reliable for estimating renal function in older adults?

No — unreliable

When should Cockcroft-Gault be used?

When dosing guidance specifies CrCl

What does Cockcroft-Gault estimate, and in what units?

Creatinine clearance (mL/min)

What are the usual units for eGFR?

mL/min/1.73 m² (indexed)

When should creatinine-cystatin C eGFR be considered?

When estimates are uncertain (e.g., low muscle mass or borderline result)

What is the Cockcroft-Gault equation for men?

CrCl = (140 − age) × weight (kg) / (72 × serum creatinine)

How is Cockcroft-Gault adjusted for women?

Multiply by 0.85

What does Cockcroft-Gault require? (select all that apply)

1. Stable creatinine 2. Clinical judgment 3. Weight choice based on body size and dosing guidance

78-year-old male, 70 kg, SCr 1.2 mg/dL — what is his estimated CrCl?

50.2 mL/min

82-year-old female, 55 kg, SCr 0.9 mg/dL — what is her estimated CrCl?

~41.8 mL/min — a 'normal' creatinine does not reflect normal renal function

What CrCl band is 'higher estimated clearance'?

≥90 mL/min

What CrCl band is 'mildly reduced clearance'?

60-89 mL/min

What CrCl band is 'moderately reduced clearance', and what should you do?

30-59 mL/min — check drug-specific thresholds

What CrCl band is 'severely reduced clearance', and what is the concern?

15-29 mL/min — accumulation risk increases

What CrCl band is 'very low clearance', and what is the approach?

What are the steps of the practical renal dosing workflow? (select all that apply)

1. Confirm indication, kidney function, and whether creatinine is stable 2. Use the measure and units specified by the drug's dosing guidance 3. Low muscle mass or borderline result → consider creatinine-cystatin C eGFR 4. Adjust the maintenance dose, interval, or medication choice 5. Plan follow-up for efficacy, toxicity, and changing renal function

What is the labeled gabapentin (IR) dose range at CrCl 40 mL/min?

400-1400 mg/day divided BID; individualize dose

What is the metformin guidance at eGFR 30-45?

Do not initiate; reassess benefit/risk if already taking

Below what eGFR is metformin contraindicated?

eGFR

What is the Beers baclofen renal criterion?

Avoid with eGFR

Why should baclofen be avoided with eGFR

Encephalopathy risk

What does pharmacodynamics describe?

Drug effects at target tissues

What does aging alter pharmacodynamically? (select all that apply)

1. Receptor number and affinity 2. Homeostatic responses

Increased PD sensitivity in older adults raises the risk of what? (select all that apply)

1. Sedation 2. Delirium 3. Orthostasis 4. Bleeding

What PD effect do benzodiazepines have in older adults?

Increased sedation, falls

What PD effect do opioids have in older adults?

Increased respiratory depression, delirium

What PD effect do anticholinergics have in older adults?

Confusion, urinary retention

What PD effect do anticoagulants have in older adults?

Increased bleeding risk

What PD effect do antihypertensives have in older adults?

Orthostatic hypotension

What are the principles of geriatric prescribing? (select all that apply)

1. Prescribe based on indication, not habit 2. Weigh risk vs benefit for each medication 3. Consider life expectancy, function, and goals of care 4. Avoid prescribing cascades 5. Start low, go slow — but titrate intentionally 6. Reassess medications regularly

Who publishes the Beers Criteria, and what is the latest update?

American Geriatrics Society — 2023 update

What does the Beers Criteria identify?

Potentially inappropriate medications (PIMs) in adults ≥65

What does the Beers Criteria focus on? (select all that apply)

1. High-risk medications 2. Drug-drug interactions 3. Drug-disease interactions 4. Renal dose considerations

What is the intent of the Beers Criteria?

Reduce adverse drug events

What 2023 Beers change applies to aspirin?

Avoid initiating aspirin for primary prevention; consider deprescribing current primary-prevention use

What 2023 Beers change applies to rivaroxaban?

For long-term AF/VTE, avoid rivaroxaban when safer alternatives are available

What 2023 Beers change applies to warfarin?

Avoid starting warfarin for AF/VTE when a DOAC is suitable

What are the five Beers Criteria buckets? (select all that apply)

1. Medications to avoid in most older adults 2. Medications to avoid in specific diseases or syndromes 3. Medications to use with caution 4. Clinically important drug-drug interactions 5. Medications requiring dose adjustment based on renal function

How should the whole Beers tool be applied? (select all that apply)

1. Check indication and goals 2. Review all five categories 3. Document benefit, risk, and follow-up

Why are bucket 1 medications avoided in most older adults? (select all that apply)

1. High risk of cognitive impairment, delirium, and falls 2. Strong anticholinergic or sedative effects 3. Safer alternatives usually available

Which medications should be avoided in most older adults (bucket 1)? (select all that apply)

1. First-generation antihistamines 2. Benzodiazepines 3. Strongly anticholinergic antidepressants 4. Skeletal muscle relaxants

Which OTC medication should you remember when reviewing the medication list for Beers bucket 1?

Diphenhydramine

Which medications should be avoided in dementia/cognitive impairment? (select all that apply)

1. Anticholinergics 2. Sedative-hypnotics

What is the concern with anticholinergics/sedative-hypnotics in dementia?

Cognition, delirium, falls

Which medications should be avoided in Parkinson disease?

Most dopamine-blocking antipsychotics (exceptions apply)

What is the concern with dopamine-blocking antipsychotics in Parkinson disease?

Worsened parkinsonism

Which medications should be avoided in symptomatic heart failure? (select all that apply)

1. NSAIDs 2. Pioglitazone

What is the concern with NSAIDs/pioglitazone in symptomatic heart failure?

Fluid retention; worsening heart failure

Which medications should be avoided with a history of falls/fractures? (select all that apply)

1. Benzodiazepines 2. Anticholinergics

What characterizes bucket 3 'use with caution' medications? (select all that apply)

1. May be appropriate but carry increased risk 2. Risk rises with dose, duration, and comorbidities 3. Require careful monitoring and reassessment 4. Benefits must clearly outweigh risks

What is the use-with-caution risk of selected antidepressants?

SIADH, hyponatremia

What is the use-with-caution risk of dabigatran (AF/VTE)?

GI bleeding

What is the use-with-caution risk of SGLT2 inhibitors?

Infection, ketoacidosis

What is the use-with-caution risk of diuretics?

SIADH, hyponatremia

Which drug-drug interactions are clinically important per Beers? (select all that apply)

1. Opioids + benzodiazepines 2. ≥3 CNS-active medication classes 3. Anticoagulants + antiplatelets without a clear indication 4. Anticholinergic stacking

What are the common outcomes of high-risk drug-drug interactions? (select all that apply)

1. Sedation and respiratory depression 2. Falls and fractures 3. Bleeding

What is the renal-dose-adjustment chain in older adults?

↓ Renal clearance → ↑ drug exposure → ↑ toxicity risk

What is the toxicity of unadjusted gabapentin/pregabalin in reduced renal function?

Sedation, confusion

What is the toxicity of unadjusted digoxin in reduced renal function?

Arrhythmias

What is the toxicity of unadjusted DOACs in reduced renal function?

Bleeding