Elderly

Question 1

Absorption

Answer 1

reduced

Question 2

Fat stores

Answer 2

Increased therefore increase the action of fat-soluble drugs (e.g. BZD) elimination half life may be increased

Question 3

lean body mass

Answer 3

decreased therefore decreases binding of and increases the concentration of highly bound drugs (e.g. digoxin)

Question 4

plasma albumin

Answer 4

decreased therefore decreases binding and increases concentration of highly protein bound drugs (e.g. phenytoin, warfarin)

Question 5

metabolism

Answer 5

smaller liver mass, reduced blood flow and enzyme function

Question 6

Excretion

Answer 6

reduced due to smaller kidney mass, reduced blood flow and function (50% by 80 years)

Question 7

Creatinine concentration

Answer 7

normal in elderly with decreased renal function

USE GFR INSTEAD. However extreme levels of muscle mass skew GFR

Question 8

Cockrauft gault

Answer 8

preferred method over 75 years

Question 9

Phenytoin in hypoalbuminaemia

Answer 9

C measured
C corrected = ———————————-
(0.9 x albumin/42) + 0.1
0.48 with reduced renal function (CRCl<20)

Question 10

PD in elderly

Answer 10

reduced number of receptors

altered homeostatic mechanisms

Question 11

Avoid drugs:

Answer 11

alpha 1 blockers
ACh
Sedative
long t1/2
Potent CYP inhibitors

Question 12

Memantine effects

Answer 12

lowers seizure theshold

Question 13

Aims of antiparkinsonians?

Answer 13

Increase dopamine (Ropinirole, L-dopa)
reduce dopamine clearance (MAO-I)

Question 14

Covert meds

Answer 14

require MHA or AWIA certificate 47
Relatives have power of attorney?
Assessment made
Advance statement from patient?