Geri: PK

Question 1

Gastric pH
What happens to acidic drug absorption

Answer 1

Increases pH
Decreases Acidic drug absorption

Question 2

Gastric emptying rate?
In OR De

Answer 2

Decreased rate
Max concentration reached later

Question 3

Splanchnic blood flow

In OR de

Answer 3

Decrease
Decreaes absorption

Question 4

GI motility

De OR in

Answer 4

Decrease

Question 5

Absorption SA

In OR de

Answer 5

Decreases

Question 6

Body fat

In OR de

Answer 6

Increases

INCREASES Vd and t1/2 of
lipophilic drugs

Question 7

Total body water

Answer 7

DECREASES

Increases plasma concentration of hydrophilic drug

Ie. For water soluble drugs = decrease Vd, increase blood concentrations (as water component decreases)

Eg. Gentamicin, dioxin, ethanol, theophylline, cimetidine

Question 8

Serum albumin (protein binding)

Answer 8

Decreaes

Increases free fraction of protein bound acidic drug

Question 9

A1 glycoprotein

Answer 9

Increase or stays same =
Increaes binding of basic drugs

Question 10

Hepatic blood flow

Answer 10

Decrease

Decrease first pass metabolism
Decrease conversion of prodrug
Ie. Changes rate of phase 1 metabolism

Question 11

Hepatic mass

Answer 11

Decreases

Question 12

Enzyme activity

Answer 12

Decreases

Question 13

Renal blood flow and GFR

Answer 13

Decreases
Decrease renal clearance

Question 14

Best predictor of response to meds?

Answer 14

Measures of FRAILTY

NOT AGE

Question 15

Body fat

Answer 15

Increases

Question 16

Most systems are more affected by disease than age alone

Answer 16

TRUE

diseases = comorbidities

Question 17

Gastric secretions
Intestinal motility

Answer 17

Both Decreased

Question 18

Absorption rate?

Answer 18

Slowed down (but extent not)

Question 19

IM dosing?

Answer 19

Decrease tissue perfusion = delay dissolution

Question 20

Topical- transdermal

Answer 20

Reduced skin hydration = delayed release

Question 21

Blood concentrations are higher
True or false

Answer 21

True

Question 22

Hepatic extraction (HE)

Answer 22

Reduced liver perfusion = decrease in clearance of high HE drugs
(Ie. Verapamil, propranolol, lignocaine)

= blood flow limited metabolism

Drugs with low HE (capacity limited) will not be affected)

Question 23

How much % does hepatic blood flow decline by per year

Answer 23

1% every year after 30

Question 24

Pharmacodynamic EFFECT?

Answer 24

Elderly have pharmacodynamic differences due to reduced resistance to external stressors

Question 25

PD.

RECEPTOR PROPERTIES
EXAMPLR

Answer 25

Reduced Beta- adrenoceptor fucntion =

1. Reduced myocardial sensitivity to catecholamines
2. Reduced response to salbutamol and propranolol

Question 26

What are 1/3 of ADR related to?

Answer 26

Impaired renal function

Question 27

PD. Homeoststic mechanism changes

Answer 27

Counter regulatory measures are reduced

Eg. Orthostatic hypotension through decreased baroreceptor responsiveness

AND

DRUG INDUCED ORTHOSTATIC HYPOTENSION

Question 28

PD. Hypoglycaemia

Answer 28

Drug induced: long acting sulfonyureas

Question 29

PD. CNS effects of drugs

Answer 29

Vulnerable to side effects…
Delirium, EPSE, arrhythmias, postural hypotension

B/w 20-80 yo. Brain weight reduces by 20%

Question 30

PD. BENZOS

Answer 30

Greater sensitivity to actions of benzo

Dose adjustment due to PD not PK.

Question 31

PD in wafarin

Answer 31

INR not effective marker in elderly.

Also,

-organ function (liver)
-dietary influences (vit k)
-concomitant medicines (polypharmacy)