Geriatric Pharmacology

Question 1

How can we avoid the drug AA cascade?

Answer 1

• Avoid prescribing until test results confirm suspected diagnosis
• Start with low dose then titrate
• Avoid starting multiple meds at the same time
• Reach theraputic dose b4 switching or ading agents

Question 2

What is the drug AA cascade?

Answer 2

Drug 1 => AA 1 confused as new disease =>Drug 2 = AA 2 confused as new disease

Question 3

What are the causes of drug related problems?

Answer 3

Drug interactions
Inadequate monitoring
Innapropriate drug selection
Innapropriate Tx
Lack of Pt adherence
Overdosage
Under Prescribing
unTx medical Problem

Question 4

What are the tools for medication decisions in older adults?

Answer 4

Beers Criteria
STOPP
START

Question 5

What are the physiological changes that come with aging?

Answer 5

Inc. Waist Circum then plateau or decline
Increase Fat Mass

Dec. weight
Dec. LBM

Question 6

What are the physiologic changes in the liver associated with age?

Answer 6

Dec. Hepatic size

Dec. Hepatic BF

Question 7

What are the physiologic changes in the Lungs associated with age?

Answer 7

Dec. Respiratory Muscle Strength
Dec. Chest wall compliance
Dec Total alveolar surface 
Dec. Vital Capacity
Dec. Maximal breathing capacity

Question 8

What are the physiologic changes in the kidneys associated with age?

Answer 8

Dec GFR
Dec Renal Blood Flow
Dec Filtration fraction
Dec. Tubular secretory function
Dec Renal Mass

Question 9

What are the physiologic changes in the skeleton associated with age?

Answer 9

Loss of skeletal bone mass

Question 10

What are the physiologic changes in the body composition associated with age?

Answer 10

Dec. Total body water
Dec Lean body mass
Inc Body Fat

Question 11

What are the physiologic changes in the cardiovascular system associated with age?

Answer 11

Dec Myocardial Sensitivity to B adrenergic stim
Dec. Baroreceptor Activity
Dec. Cardiac output

Increased Total Peripheral resistance

Question 12

What are the parameters involved in pharmacokinetics?

Answer 12

Absorption
Distribution
Metabolism
Clearance/Elimination

Question 13

What paramenter is least effected by aging?

Answer 13

Absorption

Question 14

What is first pass inactivation?

Answer 14

Before entering systemic circulation a drug can be metabolized(inact) in the gut wall or liver, more commonly.

Question 15

What hapens to first pass metabolism in the elderly?

Answer 15

Decreased therefore,

they will need less drug to have the same theraputic effect

May need more of a drug that requires hepatic activation

Question 16

What is the equation for volume of distribution?

Answer 16

Vd= amt of drug in body/plasma drug conc.

Question 17

What happens to the Vd of a muscle bound drug in elderly pop?

Answer 17

It will decrease

Question 18

What happens to the kinetics of Lipid sol. drugs in elderly?

Answer 18

Longer HL

Question 19

What is the clearance of a drug?

Answer 19

Rate of elimination of a drug from the body in relation of drug conc.
CL = Q x E
Q=flow rate to organ
E = Extraction ratio

Question 20

What is the size of the maitenence dose?

Answer 20

Maint rate is equal to rate of clearance at steady state

Requires less frequent and lower maint dose

Question 21

What is the chemical of choice to measure Renal clearance?

Answer 21

Creatinine is filtered and not reabsorbed

Creatinine clearance is an index of GFR

Question 22

How is the Creatinine Clearance measured?

Answer 22

Compare 24 hr urine collection concentration to serum conc.

Blood conc increases and Urine conc decreases as renal function decreases

Question 23

What is the purpose of the Cockroft and Gault equation

Answer 23

Accounts for decreased muscle mass in elderly Pts

Question 24

What most significantly changes the T1/2 of drugs in the elderly?

Answer 24

Hepatic and renal clearance

Question 25

What happens to the clearance of FLOW LIMITED drugs in the elderly?

Answer 25

Dec Clearance and inc T 1/2

Question 26

What is the effect of aging on the B adrenergic system?

Answer 26

Decreases responsiveness to cardiac and vascular receptors | Dec response to Hypotensve effects of B Blockers

Question 27

What is the effect of Anesthetic sensitivity in the aging population?

Answer 27

Incresed sensitivity!

Question 28

What are considerations for NSAIDS in the elderly?

Answer 28

More succeptible to toxicity of NSAIDS Renal damage (cleared mostly by the kidneys) Prostaglandins naturally increase in the elderly to retain perfusion to the kidneys

Question 29

What are the risks of Anticholinergic drugs in the elderly?

Answer 29

Orthostatic hypotension and blurry vision =>Fall risk increases