chap 4

Question 1

___consists of 4 basic processes…absorption, distribution, metabolism and excretion

Answer 1

pharmacokinetics

Question 2

_______drugs ionize in basic alkaline media whereas ______drugs ionize in acidic media

Answer 2

acidic

basic

Question 3

____is defined as the movement of a drug from its site of administration into the blood

Answer 3

absorption

Question 4

_____is enhanced by rapid drug dissolution, high lipid solubility of the drug, a large surface area of absorption and high blood flow at the site of administration

Answer 4

absorption

Question 5

____ administration has several advantages rapid onset, precise control over the amount of drug entering the blood, suitability for use with large volumes of fluid, and suitability of irritant drugs

Answer 5

Intravenous

Question 6

to move around the body , drugs must cross____ either by passing thru pores, undergoing transport, penetrating the membrane directly

Answer 6

membranes

Question 7

____ processes determine the concentration of a drug at its sites of action, and thereby determine the intensity and time course of responses.

Answer 7

pharmacokinetic

Question 8

____administration has several disadvantages, high cost, difficulty, inconvenience, danger because of reversibility, potential for fluid overload, infection and embolism

Answer 8

Intravenous

Question 9

___administration has 2 advantages suitability for insoluble drugs and for depot preparations

Answer 9

Intramuscular

Question 10

____administration has 2 disadvantages inconvenience and discomfort.

Answer 10

intramuscular

Question 11

__administration has the same advantages and disadvantages as intramuscular administration

Answer 11

subcutaneous

Question 12

___administration has the advantages of ease, convenience, economy and safety

Answer 12

Oral

Question 13

____ administration disadvantages are high variability, possible inactivation by stomach acid, digestive enzymes, liver enzymes( because ____ must pass thru liver before reaching general circulation

Answer 13

oral

oral

Question 14

____ is defined as the movement of drugs thru out the body

Answer 14

distribution

Question 15

In most____drugs can easily leave the vasculature thru spaces between cells that compose the capillary wall

Answer 15

tissues

Question 16

The term _____refers to the presence of tight junctions between the cells that compose capiilary walls in the
CNS. so drugs must pass thru the cells of the capillary wall, rather than between them, to reach the CNS

Answer 16

blood brain barrier BBB

Question 17

the membranes to the ____ do not constitute an absolute barrier to the passage of drugs.

Answer 17

placenta

Question 18

Many drugs bind reversibly to___ . while bound to ____ drug molecules cannot leave the vascular system.

Answer 18

plasma albumin

albumin

Question 19

____is defined as the enzymatic alteration of drug structure

Answer 19

drug metabolism (biotransformation)

Question 20

Most drug metabolism takes place in the ___ and is catlyzed by the cytochrome P450 system of enzymes

Answer 20

liver

Question 21

The most importance consequence of ___ ___ is promotion of renal drug excretion by converting lipid soluable drugs into more hydrophillic forms

Answer 21

drug metabolism

Question 22

Drugs that are metabolized by P450 enzymes are called ___

Answer 22

substrates

Question 23

The rate at which ___ are metabolized is affected by drugs that act as P450 inducers or inhibitors

Answer 23

substrates

Question 24

Drugs that act on the liver to increase rates of metabolism are ____

Answer 24

inducers

Question 25

This process of stimulating enzyme synthesis in known as ____.As the rate of drug metabolism increases, plasma drub levels____.

Answer 25

induction

fall

Question 26

Drugs that act on the liver to decrease rates of drug metabolism are called_____. the process in known as ___

Answer 26

inhibitors

inhibition

Question 27

This creates a therapeutic consequences because slower metabolism can cause a _____ in active drug accumulation. this can lead to an ____ in adverse effects and toxicity.

Answer 27

increase

Question 28

the term _____ refers to the rapid inactivation of some oral drugs as they pass thru the liver after being absorbed

Answer 28

first-pass effect

Question 29

Most drugs are excreted by the ____

Answer 29

kidneys

Question 30

____ excretion has 3 steps glomerular filtration, passive tubular reabsorption, and active tubular secretion

Answer 30

renal

Question 31

Drugs that are highly ___soluble undergo extensive passive reabsorption back into the blood and therefore cannot be excreted by the kidneys until they are converted to more polar forms by the liver.

Answer 31

lipid

Question 32

For most drugs there is a direct correlation between the level of the drug in the ____ and the intensity of therapeutic and toxic effects.

Answer 32

plasma

Question 33

___ _____ is a repeating cycle in which a drug undergoes glucurnidation in the liver , transport to the duodenum by bile, hydrolytic release of free drug by intestinal enzymes , followed by transport in the portal blood back to the liver, where the cycle can begin again

Answer 33

enterohepatic recirculation

Question 34

the ___ is defined as the plasma level below which therapeutic effects will not occur.

Answer 34

MEC minimum effective concentration

Question 35

the ___ ____ of a drug lies between the MEC and the toxic concentration.

Answer 35

therapeutic range

Question 36

drugs with a ___ ___ ____ are relatively easy to use safely. drugs with a ___ ___ ___ are difficult to use safely

Answer 36

wide therapeutic range

narrow therapeutic range

Question 37

The __ ___ of a drug is defined as the time required for the amount of drug in the body to decline by 50%.

Answer 37

half life

Question 38

Drugs that have a short half life must be administered ____ frequently than drugs that have a long half life

Answer 38

more

Question 39

When drugs are administered repeatedly, their levels will gradually rise and then reach a steady ____

Answer 39

plateau

Question 40

The time required to reach plateau is ___ of dosage size although the height of the plateau will be higher with larger doses

Answer 40

independent

Question 41

For a drug with a ____ half life it may be necessary to use a loading dose to achieve plateau quickly.

Answer 41

long

Question 42

when drug administration is discontinued most 94% of the drug in the body will be eliminated over ___ __ __

Answer 42

4 half lives