Brainscape's Knowledge GenomeTM

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


See full index

CEP > Pharmacokinetics > Flashcards

Pharmacokinetics Flashcards

1
Q

Window of therapeutic index?

A

Safer is window is as big as possible
If above window then TOXIC
If lower doesn’t meet effective concentration

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

ADME

A
  1. Absorption
  2. Distribution
  3. Metabolism
  4. Excretion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Compliance

A

Patients willingness to take drugs

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

Routes of drug administration

A
  • Enteral (oral rectal)
  • Parenteral (subcutaneous/ intramuscular/ intravenous)
  • Percutaneous (inhalation/ Sublingual/ topical)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Absorption depends on:

A

Route of administration
Blood flow at site of administration
Drug solubility
Active vs passive diffusion
Dose of drug

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

What is bioavailability

A

Fraction of the total dose administered that reaches the plasma

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

Does drug diffuse directly to target organs?

A

No. Drug randomly diffuses.

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

Chemical properties of a drug:

A

Chemical nature
Molecular weight
Solubility
Partition coefficient

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

What affects the absorption of drugs from gastrointestinal tract :

A
  • formulation of drug
  • stability of drug (digestive enzymes)
  • time available for absorption (tansit time, diarrhoea)
  • lipid solubility
  • interaction with food
  • conc of drug
  • blood flow
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Pharmaceutical interventions influencing absorption:

A
  • particle size (dry powder inhaler)
  • coating of tablets
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is enteric coating of tablets?

A

Slow-release
Solid core around it and water diffuses in and releases drug

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

Factors affecting transdermal (through skin) absorption:

A
  • lipid solubility
  • formulation
  • skin thickness
  • hydration
  • blood flow
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Pinocytosis?

A

Facilitated diffusion and active transport

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

Lipophilicity?

A

Strongly decides whether a compound an pass through membrane

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

Distribution depends on:

A
  • lipid solubility
  • diffusion barriers
  • tissue binding
  • plasma protein binding (albumin)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

One compartment model?

A

Assume the body is one whole compartment

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

Pharmacokinetics view of the body (specific properties):

A
  • how many membranes
  • pH value
  • circulation
  • size of surface area
  • any diffusion barriers
  • any inactivating enzymes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Special highly regulated diffusion barriers?

A
  1. Blood brain barrier
  2. Placenta
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

AVD

A

Apparent volume of distribution

The notional volume of fluid required to dilute
the absorbed dose to the concentration found in plasma

How extensively a drug is distributed in the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the AVD of drug that is heavily plasma protein bound?

A

Low ~ 6 litres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

AVD if drug heavily tissue bound?

A

High ~ More than 70 litres
Bcs concentration of drug in the blood is lower

AVD= drug mass/ conc

22
Q

Two compartment model?

A

Central and periphery compartments
The central compartment (compartment 1) consists of the plasma and tissues where the distribution of the drug is practically instantaneous. The peripheral compartment (compartment 2) consists of tissues where the distribution of the drug is slower.

23
Q

Ion trapping?

A

Many drugs exist in eqm btw ionised and unionised forms
Only unionised form is lipid soluble and infuses through membranes
Charged molecules can’t diffuse back out so traps them

24
Q

Protonisable groups?

A

COOH
NH2

25
Q

Where will drugs tend to accumulate?

A

In area where ionisation is favoured

26
Q

Where weak acidic drugs absorbed and accumulate

A

Tend to be well absorbed from acidic environments and accumulate in basic environments

27
Q

Where Basic drugs absorbed and accumulate

A

Well Absorb from basic environments and accumulate in acidic environments

28
Q

Why are basic drugs secreted into the stomach?

A

Because of ion trapping
pH is acidic in stomach
And basic drugs accumulate in acidic environments

29
Q

Were are acidic drugs excreted?

A

In urine

30
Q

First pass metabolism?

A

Drug gets metabolised at a specific location in the body that results in reduced concentration of the active drug upon reaching site of action

31
Q

Which administrative route has a high first pass metabolism effect?

A

Orally

32
Q

How does plasma protein binding affect distribution of drug?

A

Unbound drugs free to diffuse into tissue

Med with low plasma protein binding distributed readily
Med with high binding has a longer duration of action

33
Q

Where does metabolism occur?

A

Liver (first pass metabolism)
Kidney
Skin/ lungs
Microbiome

34
Q

Why is knowledge of first pass metabolism important ?

A

Can assist the prescriber when deciding on doses and dose schedules

to ensure correct dosing by correct route for optimum effect

35
Q

In bio transformation is there reduction and oxidation of drugs?

A

No.

Mainly oxidation (via cytochrome p450 enzymes) - addition of hydroxyl groups
conjugation (attaching small polar molecules on drugs) - addition of small polar groups

36
Q

What does metabolism do to drug?

A

Usually inactivates drug but can activate them too

37
Q

Ways of Excretion of drugs?

A
  1. Kidney - into urine
  2. Liver - into bile, enterohepatic circulation
  3. Lungs - exhalation
  4. Saliva, sweat, milk
38
Q

What bodily fluids are usually used for drug analytics

A

Urine
Saliva
Blood

39
Q

Preclinical outcomes of studying pharmacokinetics

A
  • Select drugs with max potential for reaching target
  • Select appropriate route of administration to deliver drug
  • Blood levels relate to efficacy/ toxicity so an select safe doses
  • decide Frequency and duration of dosing
40
Q

What drugs have high volumes of distribution

A

Lipophillic
Basic drugs

41
Q

What drug is heavily plasma protein bound?

A

Acidic drugs

42
Q

What drug is heavily tissue bound?

A

Basic drugs

43
Q

What is the definition of pharmacokinetics

A

Study of the movement of drugs in the body

44
Q

What does it mean if AVD is high

A

Less drug stays in blood (vascular space)
More drugs absorbed into organ systems

45
Q

What does it mean if AVD is low

A

More drug stays in vascular space

46
Q

Distribution in two compartment models

A

Distribution takes time
Not instantaneous like one compartment model

47
Q

AVD of two compartment model

A

AVD becomes larger until eqm is reached and as drug distributes further

48
Q

Why has two compartment model got a bi exponential decline

A

Initially decline is plasma drug conc due to elimination and distribution (steep)
Later decline in plasma drug conc due ONLY to elimination (slower)

49
Q

What is the AVD for one compartment model

A

Constant from beginning

50
Q

Why is one compartment model mono exponential

A

Decline in plasma drug corn is ONLY due to elimination

CEP (12 decks)

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