Week 3

Question 1

What is pharmacokinetics?

Answer 1

What the body does to the drug: absorption, distribution, metabolism, excretion

Question 2

Things that affect pharmacokinetics:

Answer 2

Age
Pregnancy 
Hepatic/renal disease 
Drug interactions
Ethnicity 
Metabolism
GI surgery
Nutritional status

Question 3

What is the fraction of unchanged drug teaching systemic circulation?

Answer 3

Bioavailability

Question 4

Rate at which drug leaves site of administration and passes to systemic circulation. How drug enters the body.

Answer 4

Absorption

Question 5

Factors affecting absorption:

Answer 5

Presence/absence of food in stomach
Blood flow to area
Formulation of drug
Size of molecule 
Ionization 
Cellular environment
Lipophilicity
Mechanism of absorption: passive diffusion or active transport

Question 6

A drug that is more basic will be absorbed where:

Answer 6

A more basic environment such as small intestines

Question 7

A drug that is more acidic will be absorbed:

Answer 7

In a more acidic environment like the stomach

Question 8

This enhances renal clearance of drugs during toxicity.

Answer 8

Ion (drug) trapping

Question 9

With an acidic drug overdose what would you give for ion trapping?

Answer 9

Sodium bicarbonate to make urine more alkaline and prevent reabsorption

Question 10

For a basic drug overdose, what would you give?

Answer 10

Ammonium chloride to make more urine more acidic and prevent reabsorption

Question 11

Most drugs are absorbed through the GI tract by:

Answer 11

Passive diffusion

Question 12

How the drug will distribute through the body:

Answer 12

Volume of distribution

Question 13

Volume of distribution depends on:

Answer 13

Solubility
Charge
Size

Question 14

Larger Vd will concentrate where:

Answer 14

In tissues of the body- lipophilic drugs

Question 15

Smaller Vd concentrates:

Answer 15

In the plasma- hydrophilic drugs

Question 16

Properties affecting distribution:

Answer 16

Molecular size
Lipid solubility
Ph of environment
Ionization

Question 17

A high degree of plasma protein binding can result in:

Answer 17

Restricted drug distribution

Question 18

Active drugs being made less active to be excreted:

Answer 18

Metabolism/biotransformation

Question 19

Metabolism occurs primarily here:

Answer 19

Liver

But also: intestines, skin, lungs, kidney, and brain

Question 20

An inactive drug that becomes active with metabolism:

Answer 20

Prodrug

Question 21

Phase I reactions occur through:

Answer 21

Oxidation (most common), reduction, and hydrolysis

Question 22

What system does phase I metabolism occur:

Answer 22

Most often cytochrome 450 system

Question 23

Goal of Phase I reactions:

Answer 23

Parent drug converted to a drug more easily excreted/water soluble.

Question 24

With aging the livers capacity for metabolism through the P450 system is ___

Answer 24

Reduced by 30%

This drugs metabolized through this system reach higher levels and have prolonged half lives in the elderly

Question 25

Explain CYP450 enzyme induction:

Answer 25

An inducing agent can increase the metabolism of another drug, resulting in the effect of the second drug being reduced. This can lead to therapeutic failure of the second drug.

Question 26

Explain CYP450 enzyme inhibition:

Answer 26

An inhibiting drug can decrease the rate of metabolism of another drug, causing the second drugs level to rise and possibly result in harmful or reverse effect.

Question 27

Phase II reactions are these types of reactions:

Answer 27

Glucurondiation Acetylation Sulfation

Question 28

Phase II causes drugs to:

Answer 28

Conjugate with another substance to make drug more water soluble and easier to excrete.

Question 29

Patients deficient in acetylation capacity (slow acetylators) may have:

Answer 29

Prolonged or toxic responses to normal doses of certain drugs bc of decreased rates of metabolism .

Question 30

Factors affecting metabolism:

Answer 30

``` Age Gender Drug tolerance Co-morbidities Drug-drug interactions Genetic differences Diet and environment factors ```

Question 31

Primary site of excretion is:

Answer 31

Kidney

Question 32

Filtration works well for:

Answer 32

Hydrophilic, ionized compounds

Question 33

Process of drugs being transferred from inside to outside the body.

Answer 33

Excretion

Question 34

What types of drugs use biliary excretion:

Answer 34

Usually larger molecular weight drugs- erythromycin

Question 35

Some ___ soluble drugs will get passively reabsorbed into circulation .

Answer 35

Lipid

Question 36

Factors affecting renal excretion:

Answer 36

Renal function Protein binding Renal disease

Question 37

If creating is elevated then creative clearance is

Answer 37

Decreased - drug will not be as easily excreted and there is an increased potential for toxicity

Question 38

At a steady state, rate of clearance should be:

Answer 38

Equal to the amount of drug taken in

Question 39

Time it takes the peak drug level in the bloodstream to drop by half after elimination from the body.

Answer 39

Half-life

Question 40

High enough to maintain effect, low enough to prevent toxicity.

Answer 40

Steady state

Question 41

Refers more broadly to the genome-wide (or an individuals entire DNA sequence) effects on drug therapy

Answer 41

Pharmacogenomics

Question 42

Refers to a single or a few gene variations (called polymorphisms)

Answer 42

Pharmacogenetics

Question 43

Poor metabolizers:

Answer 43

Slowly metabolize drug causing increase of drug in system

Question 44

Poor metabolizers should have an increase or decrease in dosage?

Answer 44

Decrease

Question 45

Ultra-rapid metabolizers:

Answer 45

Have an increased metabolism of drug causing therapeutic failure of drug

Question 46

Ultra-rapid metabolizers need an increase or decrease in dosage?

Answer 46

Increase in dose to have effect

Question 47

What will happen with a prodrug and an ultra rapid metabolizers?

Answer 47

Will become more active and become potentially toxic