Polypharmacy and Drugs

Question 1

Absorption changes in elderly

Answer 1

Rate effected -> delay in onset of action

Question 2

Distribution changes in the elderly

Answer 2

Reduced muscle mass
Increased adipose tissues (fat soluble drugs)
- increase vD
- increased half life
- increased duration of action
Decreased body water (water soluble drugs)
- decreased vD
- increased serum levels acidic e.g. furesimide
Increased permeability across BBB

Question 3

Metabolism changes in the elderly

Answer 3

Hepatic metabolism 
- decreased liver mass
- decreased liver blood flow
Leading to 
- toxcitiy 
- decreased first pass metabolism ( increased and decreased bioavailability)

Question 4

Excretion changes in the elderly

Answer 4

Renal function decreases with age

Decreased clearance and increased half life of drugs = toxicity

Question 5

What is pharmacokinetics?

Answer 5

What the organism does to the drugs

Question 6

Features of pharmacokinetics

Answer 6

Absorption
Distribution
Metabolism
Excretion

Question 7

Pharmacodynamics in the elderly

Answer 7

increased sensitivity to particular medicines due to 
- change in receptor binding 
- decreased receptor no 
- altered response 
e.g. diazepam = increased sedation 
Warfarin = increased anticoagulation

Question 8

Drug-disease interactions in the elderly

Answer 8

Older people = more chronic diseases
Diseases can affect drug pharmacokinetics
Drugs can worsen diseases

Question 9

Drug-drug interactions in the elderly

Answer 9

Older people have more chronic diseases
Likelier to be on more drugs
Drugs can interact leading to changes

Question 10

What does polypharmacy mean?

Answer 10

Many drugs

Question 11

What is ‘creeping cardex’ syndrome?

Answer 11

Drugs for preventative reasons but not reviewed
drugs for short term symptomatic relief but never stopped
Drugs to relieve side effects of other drugs

Question 12

Drugs most associated with admission due to ADRs

Answer 12

NSAIDs
Diuretics
Warfarin 
ACEIs
Anti-depressants

Question 13

What is hypotraemia associated with?

Answer 13

Risks of falls and fractures

Question 14

Prescribing tools and guides

Answer 14

Beers criteria
START-STOPP criteria
NHS Scotland polypharmacy guidance

Question 15

Reasons for de prescribing

Answer 15

ARDs
disease drug interactions
drug drug interactions
better alternative
not effective
not indicated
not evidence based
minimise polypharmacy

Question 16

What is de-prescribing?

Answer 16

To reduce, substitute or discontinue a drug

Question 17

Psychiatric treatment in the elderly

Answer 17

Care with treating "agitation"
Increased effects of sedative (falls, confusion)
Antipsychotic S/Es
- postural hypotension 
- stroke
- confusion 
- movement disorders
Antidepressants less effective

Question 18

Analgesia in the elderly

Answer 18

lower dose of opoids needed (more sensitive)
Increased adverse effects of NSAIDs
- renal impairment
- GI bleeding

Question 19

CVS drugs in the elderly

Answer 19

Digoxin = increased toxicity so less doses needed
Diuretics
- decreased clearance (abnormal U and Es)
- Continence and mobility issues
- often innapropriate indication (swelling)
Anti HTNs
- exaggerated BP and HR effects
- postural hypotension
- ACEIs may not be in active form
- renal adverse effects
Anticoagulants
- more sensitive to warfarin and increased risk from it

Question 20

Antibiotics in the elderly

Answer 20

Increased adverse effects

• diarrhoea
• C diff infection
• blood dyscarias (trimethoprim)
• delirium (quinolones)
• Seizures
• Renal impairment