Pharm Unit 3-2

Front 1

1. Membrane structure
lipid bilayer with proteins
pores
complexes
2. Drug passage through membrane proper influenced by lipid solubility
3. Drug passage through pores is influenced by: shape and size of the molecule and degree of ionization (charge)

Back 1

How do drugs pass membranes to reach their targets?

Front 2

lipid bilayer with proteins

Back 2

Chiefly lipids pass through this way to their targets.

Front 3

pores

Back 3

chiefly for small water soluble substances

Front 4

complexes

Back 4

chiefly for carrier mediated transport

Front 5

lipid

Back 5

Drug passage through membrane proper influenced by _______ solubility.

Front 6

size and shape of the molecule

degree of ionization

Back 6

Drug passage through pores is influenced by WHAT?

Front 7

degree of ionization

Back 7

charge

ions are less able to move passively

influenced by pH (less ionized in like environment, more ionized in opposite pH.

Front 8

acidic drugs

Back 8

LESS ionized at low environment pH, more ionized at high environment pH (ex. aspirin and barbiturates)

Front 9

alkaline drugs

Back 9

less ionized at HIGH environmental pH, more ionized at low environment pH (ex. morphine or quinine -- endings -ine or -amine indicate alkaline drugs)

Front 10

The concentration at the active site might differ

The active site response differs

The patient might have other conditions or issues affecting drug responses

Back 10

For a given dosage of a drug, patients do not always respond the same: Why not?

Front 11

pharmacokinetics

bioavailability

Back 11

Concentration of drug at active site - depends upon _____________, i.e. absorption, distribution, metabolism (biotransformation), and excretion of a drug - ____________.

Front 12

Absorption

Back 12

Transfer of drug molecules from place deposited to circulating fluids.

Front 13

Absorption

Back 13

1. route of drug administration
2. local conditions at site of administration
3. chemical properties of drug
4. form of medication given alters absorption

Front 14

injections are usually more rapidly absorbed than oral route

Back 14

What is the route of drug administration for faster absorption?

Front 15

absorbed
oral

Back 15

injections are usually more rapidly ________ than the _____ route.

(contrast plot of drug plasma concentration vs. time for oral route and IV administration)

Front 16

amount of circulation to area
patient in shock
tourniquet or cooling

Back 16

What are the local conditions at the site of administration, if injected?

Front 17

pH
presense of food

Back 17

What are the local conditions at the site of administration, if oral?

Front 18

lipid solubility vs. water solubility

size and shape of molecule

degree of ionization (if water soluble)

Back 18

For absorption of a drug to occur, what are the chemical properties of that a drug needs?

Front 19

absorption

dosage

Back 19

Form of medication given alters _________.
This is in addition to change in concentration that results from different ________ or frequency of administration.

Front 20

enteric coating
time release

Back 20

For an ORAL drug, what type or form of medication should be given to alter the absorption?

Front 21

suspensions and gels can delay absorption of a given drug.

Back 21

For an INJECTION drug, what type or form of medication should be given to alter the absorption?

Front 22

Distribution

Back 22

Manner in which a drug is transported by the bloodstream to various areas of the body and the drugs ability to accumulate in some tissues or its failure to enter other regions in significant amounts.

Front 23

bloodstream
tissues

(def of distribution)

Back 23

Manner in which a drug is transported by the ___________ to various areas of the body and the drugs ability to accumulate in some ________ or its failure to enter other regions in significant amounts.

Front 24

Distribution

Back 24

a. relative perfusion and permeability of area

b. binding to non-receptor sites like plasma proteins (albumin)

c. other storage sites (body fat, muscle, liver, kidneys, bone)

d. body weight (dose given per Kg body weight)

e. sex (female smaller, but more fat)

Front 25

perfusion

permeability

Back 25

Relative __________ and _________ of area.

blood brain barrier
placental barrier

Front 26

blood brain barrier

Back 26

capillaries less permeable
-glial cells close to caps
- pores are smaller
less interstitial space-packed with glial cells
*lipid soluble drugs penetrate

Front 27

lipid soluble drugs penetrate

Back 27

What type of drug can penetrate the B.B.B.?

Front 28

placental barrier

Back 28

many things do pentrate.

-rate of blood flow limits drug passage (anesthetic - 10 to 15 mins)
-particles as large as RBC's can cross
-lipid soluble drugs cross most readily
ex. narcotics, barbiturates, alcohol, tetracycline (retard bone growth)

Front 29

non-receptor sites

def. of distribution

Back 29

Distribution of drug binds to ___________ ____ like plasma proteins (albumin).

Front 30

binding to non-receptor sites

Back 30

What part of distribution is this?

can affect onset, intensity, and duration (due to decreased excretion rate)

usually weak binding so effect not severe

sometimes use PRIMING dose then smaller maintenance dose.