Lecture 2- Pharmacokinetics Flashcards

1
Q

Pharmacokinetics is

A

-A subfield of pharmacology
-Absorption, distribution, bio transformation and excretion of drugs
-Movement of drug to and from its site action

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

Factors that determine the movement of drugs to terminals

A

-How much gets there
-How fast it gets there
-How long it’s there

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

Factors affecting absorption

A

-Drug solubility
-Ionisation
-Blood circulation at the site of administration
-Surface area of the absorbing surface

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

What factors of absorption are determined by route of administration

A

-Blood circulation at site of administration
-Surface area of absorbing surface

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

What is PO

A

PreOral
Absorption through gastrointestinal tract (not mouth)

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

Routes that avoid 1st pass metabolism

A

-Nasal
-Sublingual
-Rectal
-Transdermal
-Pulmonary absorption

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

Levels of transmission

A

-Subcutaneous
-Intramuscular
-Intravenous

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

Where is the subcutaneous

A

Just below the skin

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

Where is the intramuscular level

A

In the muscle

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

Where’s the intravenous level

A

Just the spinal cord

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

Putting a drug in an oil solution can

A

Slow down the release of the drug

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

What is peak effect

A

Highest point of concentration in the blood

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

Drug peak concentration and half life vary by

A

Route of administration

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

Half life is

A

Time for plasma drug concentrations to fall to half of peak effect

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

Effects of route administration

A

-Amount of drug destroyed by 1st metabolism
-Blood circulation at the site of administration
-Surface area available for absorption
-Binding to inactive sites
-Number of cell layers to blood

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

Drug movement across membranes is a key factor influencing

A

The dose available at site of action

17
Q

Limiting factors of drug movement across membranes

A

-Size and shape of drug molecule
-Lipid solubility and ionisation

18
Q

Which reaches the brain first heroin or morphine

19
Q

Drugs that are weak acids ionise more in

A

Basic (alkaline) environments (solvents)

20
Q

Drugs that are weak bases ionise more in

A

Acidic environments (solvents)

21
Q

The greater difference in environment and drug

A

The more ionised the drug is and less absorption

22
Q

To know whether a drug is lipid soluble, you have to know

A

-Whether it’s a weak acid or base
-Pka value
-Solution your putting it in

23
Q

What is ion trapping

A

Build up of a higher concentration of a chemical across a cell membrane due to the pka value of the chemical and difference of pH

24
Q

What is the blood brain barrier

A

Special barrier protecting the brain, molecules travel everywhere but the brain

25
Brain areas outside the blood brain barrier
-Area postrema (vomiting center) -Median eminence (hypothalamic hormones)
26
Features of typical capillary membranes
-Made of endothelial cells -Fenestration -Pinocytotic vesicles -Lipid soluble transport -Intracellular cleft
27
What can still diffuse through brain capillaries
Lipid soluble molecules such as psychoactive drugs
28
Features of brain capillaries
-Made of endothelial cell -Tight junction -Surrounded by astrocytes
29
Most of metabolism occurs in
The liver
30
Inactivation usually due to
Metabolism
31
What mechanism do psychoactive drugs most often move across cell membranes
Simple diffusion
32
True or false Metabolites are always inactive
False
33
True or false, there are sex differences in enzyme activity in the stomach
True
34
True or false, metabolism usually reduces the solubility
True