Brainscape's Knowledge GenomeTM

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


See full index

Pharmaceutics > Introduction to Biopharmaceutics > Flashcards

Introduction to Biopharmaceutics Flashcards

1
Q

What is biopharmaceutics?

A

The study of how the physiochemical properties of drugs, dosage forms + routes of administration affect the rate + extent of drug absorption

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

What is plasma conc?

A

Measurements of drug in the body usually limited to blood or plasma

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

What happens in oral administration?

A 
Drug release + dissolution
Absorption into system circulation 
Elimination = excretion or metabolism 
OR
Distribution = drug in tissues = pharmacological effect
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What happens in IV administration?

A

System circulation
Elimination = excretion or metabolism
OR
Distribution = drug in tissues = pharmacological effect

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

What assumptions do we make?

A

Drug conc in plasma increases
= increases drug conc at target site
= increases pharmacological effect

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

What happens if you inject single dose?

A

Plasma conc will not stay like that forever

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

What does graph look like for IV?

A

At T=0 high conc

Then decreases over time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What happens if plasma conc is in the toxic range?

A

Experience serious side effects

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

What is therapeutic window?

A

Between min toxic range and min effective conc

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

What happens if drug conc is in the sub-therapeutic range?

A

Drug will have no effect

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

Why is a 2nd dose given?

A

To increase plasma conc to therapeutic window

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

What is onset time?

A

Plasma conc first exceeds minimal therapeutic conc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

When is the onset time for IV + why?

A

T=0

= rapid onset of action

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

What is duration of action?

A

Time within therapeutic window

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does the area under the curve tell us?

A

Total exposure to the drug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the duration of action dependent on?

A

Initial conc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How do you calculate rate of elimination?

A

Kel X D

18
Q

What is plasma half life?

A

Time taken for plasma conc of a drug to fall by 50%

19
Q

Is plasma half life constant?

A

YES

20
Q

How does plasma half life proceed?

A

1st order reaction

21
Q

What does rate depend on?

A

Initial drug conc

22
Q

What is long plasma half life?

A

Plasma conc will remain in therapeutic window for longer

23
Q

What happens if you have a shorter half life?

A

You need more frequent dosing

24
Q

What can dosing also depend on?

A

How narrow or wide therapeutic window is

25
Q

What is vol of distribution?

A

Theoretical fluid vol needed to contain the drug at same conc found in the plasma

26
Q

What is vol of distribution affected by?

A

Plasma proteins

27
Q

What does it mean if there is a larger vol of distribution?

A

Distribution of drugs into tissues

28
Q

What happens to bound drugs?

A

Confined to plasma

29
Q

What happens to unbound drugs?

A

Can be distributed into tissues

30
Q

What does there mean if there is a high bound drug fraction (fb)?

A

Lower vol of distribution

31
Q

What is clearance?

A

Vol of plasma from which the drug is eliminated per unit time

32
Q

How is the drug eliminated?

A 
Metabolism = liver
Excretion = kidneys
33
Q

Describe the graph for oral administration

A

Conc starts at 0
Then increases to a peak = Cmax
Then decreases again

34
Q

What is Tmax?

A

The time taken to reach Cmax

35
Q

How do you calculate exposure?

A

Area under curve (AUC)

36
Q

What happens before Cmax is reached in the oral administration graph?

A

Drug is being absorbed in GI tract

37
Q

What is bioavailability?

A

Fraction (%) of dose that reaches systemic circulation

38
Q

What is the bioavailability fraction for IV?

A

F = 1 as entire dose is administered into bloodstream

39
Q

What is the bioavailability for oral?

A

F < 1 due to pre-systemic effects

40
Q

How many food affect drug stability, dissolution + absorption?

A

Change change pH = slow dissolution

Food components, bile salts, gastric retention + enzyme activity

41
Q

What is bioequivalence?

A

Equivalent rate + extent of absorption between formulations

42
Q

What must AUC, Tmax + Cmax all fall within to be considered bioequivalent?

A

80-125%

Pharmaceutics (21 decks)

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