Polypharmacy and prescribing

Question 1

What are common adverse drug reactions in older people?

Answer 1

Unsteadiness
Dizziness
COnfusion
Nervousness
Fatigue
Insomnia
Drowsiness
Dehydration
Incontinence
Depression

Question 2

What are the changes in absorption in older people?

Answer 2

physiological changes to GI tract affects rate but not extent of absorption

Question 3

What are the categories of changes in drug distribution?

Answer 3

Body composition change
Change in protein binding
Increased permeability across blood brain barrier

Question 4

How does change in body composition change drug distribution?

Answer 4

Reduced muscle mass
Increased adipose tissue- increase distribution and duration of action
Reduced body water- decreased distribution, increased serum levels

Question 5

How does change in protein binding change drug distribution?

Answer 5

Decreased albumin- decrease binding, increase serum levels

Question 6

How does drug metabolism change in older people?

Answer 6

Decreased liver mass and blood flow

Question 7

What are the consequences of decreased hepatic metabolism?

Answer 7

Toxicity

Reduced first pass metabolism- change in bioavailability

Question 8

How does drug excretion change in older people?

Answer 8

Decreased renal function- reduces clearance and increases half life

Question 9

Why are older people particularly sensitive to particular medicines?

Answer 9

Change in receptor binding
Decrease in receptor number
Altered translation of receptor initiated cellular response into biochemical reaction

Question 10

What are the principles of prescribing in older people?

Answer 10

Consider whether drug therapy best option
Lower doses or reduced frequency generally required
Review regularly
Keep regimes as simple as possible