Brainscape's Knowledge GenomeTM

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


See full index

Physiology And Pharmacology > Pharmacokinetics > Flashcards

Pharmacokinetics Flashcards

1
Q

What is Pharmacokinetics?

A

What the body does to drugs

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

What are the main processes in drug therapy?

A

Drug in- Absorption and Distribution

Drug out- Metabolism and Elimination

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

How can drugs be administered?

A 
Oral
Sublingual
Rectal
Intavenous
Subcutaneous 
Intramuscular
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Where is most of a drug absorbed?

A

Small intestine

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

How is the drug absorbed?

A

Passive diffusion-lipophilic drugs and weak acids and bases
Facilitated diffusion- solute carrier
Secondary Active transport- solute carrier
Pinocytosis

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

What factors can affect drug absorption?

A 
Gi length
Drug lipophilicity
Density of SLC (solute carrier) expression in GI 
Blood flow
GI motility
Food IpH (low ph destroys some drugs)
Gut lumen enzymes
Gut wall
Liver
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a phase I enzyme?

A

Cytochrome P450s

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

What is a phase II enzyme?

A

Conjugating

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

What is bioavailability?

A

Fraction of a defined dose which reaches its way into a specific body compartment Usually CVS is used

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

What are the two routes of bioavailability?

A

Oral and IV

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

How do you work out bioavailability?

A

Amount reaching systematic circulation divided by total drug given IV

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

What do drugs usually bind to?

A

Proteins

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

What is the problem with drugs binding with plasma or tissue?

A

Can not bind to target site

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

How much is all the body water in the body?

A

42 litres

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

How do drugs travel?

A

From plasma
To interstitial fluid
To intracellular fluid

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

What is Vd?

A

Apparent volume of distribution
Model grouping of main fluid compartments as thought all one compartment.
If small means less penetration of interstitial and intracellular compartment
If big means more penetration of interstitial and intracellular compartments

17
Q

How do you work out volume of distribution?

A

Drug dose/plasma drug

18
Q

What does elimination remove?

A

Exogenous and endogenous molecular species

19
Q

Where does drug metabolism take place?

A

Liver

20
Q

What is drug metabolism phase I?

A

Cytochrome P450 enzymes
Catalyse reactions such as redox, dealkylation, hydroxylation
Directly eliminate or may move onto phase II
May activate prodrugs e.g. Codeine to morphine

21
Q

What is drug metabolism phase II?

A

Cytosolic enzymes
Increase ionic charge
Catalyse sulphation, glucorinadation, gluthione conjugation, methylation and nacetylation
Enhances renal elimination

22
Q

What are the three super families of cytochrome p450?

A

CYP 1,2 and 3

Most of drugs transformations

23
Q

What factors affect drug metabolism?

A 
Age 
Sex
General health
Other drugs
Genetic variability
24
Q

What is cyp450 induction?

A

Concurrent administration of drugs can induce specific cyp450 isozymes
Via transcription and translation and slower degradation
Plasma levels of the drug will then fall
Takes 1-2 weeks
E.g. CBZ is an anti-epileptic

25
Q

What is cyp450 inhibition?

A

Competitive or non competitive inhibition
Plasma levels of drug increase
E.g. Grape fruit juice reduced BP

26
Q

What is the route of drug elimination?

A

Kidney is main route

27
Q

How are drugs renally excreted?

A

Glomerular filtrate
Active tubular secretions
Passive tubular reabsorption

28
Q

What is Henderson hasselbach?

A

If tubular pH and molecule species pKa favourable

Get neutral AH or B species reabsorption by blood

29
Q

What is clearance?

A

Rate of elimination of a drug from the body
Total clearance is Hepatic clearance and renal clearance

The volume of plasma that is completely cleared of the drug per unit time

30
Q

What does clearance show?

A

how long a drug stays in the body

31
Q

What is a drugs half life?

A

The amount of time over which the concentration a drug in plasma decrease to one half of that concentration value when it is first measured

32
Q

Why is elimination linear?

A

Rate of metabolism or excretion is proportional to concentration of drug

33
Q

What does saturated mean?

A

Rate limited
Cannot go any faster
Zero order

Physiology And Pharmacology (8 decks)

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