Therapeutic Drug Monitoring Flashcards Preview

Clinical Chemistry > Therapeutic Drug Monitoring > Flashcards

Flashcards in Therapeutic Drug Monitoring Deck (44)
Loading flashcards...
1

MEC

minimum effective concentration

2

MTC

minimum toxic concentration

3

Trough

lowest drug level
draw sample prior to next dose given

4

peak

highest drug level, draws at peak of absorption for particular drugs

5

steady state

drug intake & outtake equal so drug level stays in therapeutic range

6

bioavailability

unchanged drug entering the bloodstream

7

# of doses to get to therapeutic range usually

at least 5 doses

8

Drug distribution

administration
absorption
distribution
excretion

9

methods that lead to GI absorption

oral, rectal or sublingual routes of administration

10

GI absorption

drugs go through the liver & go through 'first pass'
drug must go through unionized (hydrophobic), absorb passive diffusion
portion of unchanged drug entering the blood is bioavailable

11

injected drugs absorption

enter the blood stream via IV, intramuscular, intradermal, subcutaneous, respiratory, or percutaneous
do not have to deal with liver's first pass effect

12

factors that change drug absorption in GI

GI motility
pH
inflamed

13

carrier proteins of drugs

albumin & alpha-1-acid glycoprotein (!!!)

14

free drug levels affected by:

protein binding
disease state
kidney function
additional drugs being present
hepatic disease
acid-base disturbance
nephrotic syndrome

15

lipid soluble drug distribution

travel through cell membranes & partition in lipid compartments in cells

16

polar drug distribution

travel to water part of cell & stay there

17

ionized drug distribution

diffuse slowly out of blood & into cells
get filtered in kidneys or taken out by liver

18

major organ for drug metabolism

liver via mixed function oxidase system or MFO
converts hydrophobic drug into water soluble substances
go out bile or into blood & out the kidney

19

secondary sites for drug metabolism

lungs
kidneys
skin
brain
GI

20

drug metabolite activity levels

bound drug & active metabolite

21

metabolism of lipid soluble drugs

non-polar to soluble form using renal excretion via hydroxylation, deamination, sulfoxidation, dealkylation
enzymes: Monooxygenases or mixed function enzymes (MFO) in liver

22

MFO phase I

produce reactive intermediates from drug
can accumulate & may not be able to go into phase iI

23

MFO phase II

conjugates reactive intermediate to water-soluble products
intermediates are conjugated to glutathione, glycine, phophate or sulfate

24

MFO system influenced

process is inducible
drug-drug interactions are competing for MFO system
changes in hepatic health will affect MFO

25

renal clearance

parent drug & metabolite are subject to glomerular filtration
if renal function is compromised, then longer half-life

26

acid urine

leads to more alkaline drug excretion & vice versa

27

samples

usually serum/plasma
urine samples are used when wanting to look at parent drug & metabolites

28

cardiac drugs

digoxin/ digitoxin
quinidine
procainamide
disopypramide/norpace

29

digoxin/digitoxin

used for CHF
very toxic - tissue levels are 15-30x the serum/plasma level
stays in lipid portion of tissues
stops Na/K ATPase pumps to prevent fluid build up in cells & encourage K to be excreted in the urine

30

quinidine

DO NOT MIX W/ DIGOXIN
cardiac drug