Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Hugh's MD1 Abdominal > Pharmokinetics > Flashcards

Pharmokinetics Flashcards

1
Q

Which part of the GIT are oral drugs primarily absorbed?

A

Small intestine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is a potential problem with drugs that have slow distribution?

A

They are eliminated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a potential complication with low bioavailable drugs?

A

They are more sensitive to variability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Why is the peak drug concentration for oral administration lower than IV?

A

Drug is eliminated while being absorbed

Not all drug is absorbed

Some drug undergoes first past metabolism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How do you prevent drug accumulation with zero order drugs?

A

Give small doses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is renal clearance dependent on?

A

Drugs filtration and secretion (out of the blood) and reabsorption (but into blood)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a loading dose for?

A

Get a drug to it’s steady state quickly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What do the elderly lack in liver metabolism?

A

Cytochrome P450

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is renal clearance?

A

The amount of blood from which drug is removed by the kidneys over time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What happens to the half life of some drugs in the neonates and the elderly?

A

Increased

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

When is complex drug behaviour most relevant?

A

When the therapeutic window is small

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is phase I metabolism?

A

Creation of a functional group on the metabolite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the relationship between C at steady state and infusion rate?

A

Directly proportional

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How long does it take for a drug to get to 99% of its steady state concentration?

A

7 half-lives

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What long does it take for babies drug metabolism to mature?

A

6 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the bioavailable for IV drugs?

A

100%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

In theory, when is steady state reached with a zero order elimination drug?

A

Never

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What enzyme subfamily does a lot of phase I metabolism?

A

Cytochrome P450

15
Q

Where are acidic drugs most lipid soluble?

A

In areas of low pH

15
Q

What is phase II metabolism?

A

Conjugation of a water soluble molecule to a functional group on drug

15
Q

What is local metabolism?

A

Metabolism prior to absorption eg in the gut or intramuscularly

16
Q

How long does it take for newborn’s renal clearance to increase to adult levels (size proportionate)

A

1 week

17
Q

When is renal function at its peak?

A

20 year olds

19
Q

What is the pattern of drug administration over time when it’s added IV?

A

Exponential excretion

21
Q

Compare the peak concentrations when drug is added IV bolus or infusion?

A

Bolus reaches a higher peak concentration for a given amount of drug

22
Q

What is the renal clearance of newborns?

A

20% of adult (size proportional)

23
Q

What must you do with drugs with small therapeutic windows?

A

Plasma monitoring

24
Q

What is the maximal GFR?

A

120ml/min

25
Q

How much relative renal clearance do 75 y.o. have?

A

50%

27
Q

What will the variation in drug concentration be when drug is given every half-life?

A

2 fold variation

28
Q

Is the peak concentration higher with a fast or slowly distributing drug?

A

Slow

29
Q

What can you do in response to an overdose?

A

Add a compound that will change the pH to the opposite of what is optimal of absorption of the overdosing drug.

Eg add NaHCO3 to make urine more basic when overdosed on acidic aspirin

30
Q

What is bioavailability?

A

The amount of active drug that enters the systemic circulation

32
Q

What happens to drug clearance as concentration in the blood increases?

A

It increases

33
Q

What does making a drug more water soluble do to its secretion?

A

Decrease its lipid solublity > less absorption into cells > more secreted

34
Q

Where is the first place drugs go when they are absorbed in the gut?

A

The Liver

35
Q

How do drugs behave if they are added IV?

A

Rapidly distribution

Act as if in one compartment

36
Q

What are the 4 possible outcomes of metabolism?

A

Inactivation of a drug

Activation of a drug

Activation of a different drug

Toxic metabolite

38
Q

When is IV infusion better than IV bolus?

A

When the therapeutic window is small

40
Q

What is the rate of drug absorption in the gut?

A

First order: dependent on the concentration

41
Q

How do most drugs get across the gut wall?

A

Diffusion through lipid membranes

42
Q

What are the typical peripheral compartment for a drug?

A

Muscle and fat

43
Q

What can be done address low bioavailability with oral administration?

A

Administer via a different route that avoid first pass metabolism

Hugh's MD1 Abdominal (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions