Polypharmacy

Question 1

What are some adverse effects of polypharmacy in elderly patients?

Answer 1

Increased falls risk
Renal impairment
increased bleeding risk
diminished cognition
over sedation
delirium
urinary incontinence
constipation
Increased mortality rate

Question 2

why are the elderly at risk of adverse outcomes to polypharmacy?

Answer 2

• altered pharmacokinetics/dynamics
• altered homeostatic responses (due to drug-drug, drug-disease interactions)
• altered compliance factors

Question 3

what changes do we see in the pharmacokinetics in elderly patients? go through each of the stages and describe what happens.

Answer 3

absorption- no change

distribution-

1. less muscle (albumin and hence protein binding capacity decreases in the elderly)
2. more dehydrated (higher serum concentration of drug bc lower volume of distribution- so may need to dose reduce),
3. more fat mass (affect lipophillic medications- actions /half life will be more prolonged; so may need to dose reduce or frequency reduce)

metabolism-

1. reduction in hepatic blood flow (affects high 1st pass drugs)
2. affected oxidative pathways and conjugation pathways (less affected than oxidative)

excretion-
1. as age increases, renal impairment increases. We determine the age/weight for renal impairment- cockroft-gold equation–> leads to reduced excretion of renally cleared drugs

Question 4

What pharmacodynamic changes do we see in the elderly?

Answer 4

drugs like inhalational anaesthetics, opioid analgesics–> have an exaggerated effect in the elderly patient

Question 5

what are some issues involved with polypharmacy?

Answer 5

cost
compliance
increased risk of drug interactions and adverse outcomes

Question 6

why might compliance be an issue with elderly patients?

Answer 6

reduced cognition
reduced dexterity
cost
patient doesn't believe they need the medication
increased side effects

Question 7

how might a GP address polypharmacy issues in an elderly patient?

Answer 7

refer to pharmacist for medication review

Question 8

list some common medications in the elderly which are commonly associated with adverse effects?

Answer 8

antihypertensives
cardiac medications
analgesics
anticoagulants
anti depressants
anti psychotics
antibiotics

Question 9

how might ace inhibitors increase falls risk in an elderly patient?

Answer 9

chronic cough–> urinary stress incontinence

hypotension–> dizziness on standing

Question 10

how might calcium channel blockers increase falls risk in an elderly patient?

Answer 10

constipation–> increase urinary frequency–> incontinence

peripheral oedema–> poor foot wear, at night elevation can cause increased fluid –> nocturia

Question 11

how might opioid analgesics cause increased falls risk in an elderly patient?

Answer 11

constipation–> leading to incontinence

narcosis–> increased drowsiness

confusion–> falls

Question 12

how might prazosin cause increased falls risk in the elderly?

Answer 12

postural hypotension–> dizziness

increased urinary frequency–> incontinence

Question 13

what is a key SE we need to consider for elderly patients on TCA?

Answer 13

confusion

urinary retention

Question 14

what are some SE of oxybutynin and what forms does it come in?

Answer 14

anticholinergic effects= dry mouth, dry eyes. urine retention, constipation, confusion
+ facial flushing

comes as a patchy or oral

Question 15

what are some SE of mirabegron?

Answer 15

increased BP
UTI
tachycardia

Question 16

what commonly used drug in geriatric patients is lipophillic

Answer 16

diazepam