GENERAL PRINCIPLES OF PHARMACOLOGY - PHARMACOKINETICS Flashcards Preview

Pharmacology > GENERAL PRINCIPLES OF PHARMACOLOGY - PHARMACOKINETICS > Flashcards

Flashcards in GENERAL PRINCIPLES OF PHARMACOLOGY - PHARMACOKINETICS Deck (43):
1

Pharmacokinetics

The study of absorption, distribution, metabolism and excretion of drugs.

2

What does “pharmacokinetics” include?

- Drug biotransformation in the organism
- Distribution of drugs in the organism
- Excretion of substances

3

The main mechanism of most drugs absorption in GI tract is

Passive diffusion (lipid diffusion)

4

What kind of substances can’t permeate membranes by passive diffusion?

Hydrophilic substances

5

A hydrophilic medicinal agent has the following property

Low ability to penetrate through the cell membrane lipids.

6

What is implied by «active transport»?

Transport against concentration gradient

7

What does the term “bioavailability” mean?

Fraction of an uncharged drug reaching the systemic circulation following any route administration.

8

The reasons determing bioavailability are

Extent of absorption and hepatic first-pass effect

9

Pick out the appropriate alimentary route of administration when passage of drugs through liver is minimized

Rectal

10

Which route of drug administration is most likely to lead to the first-pass effect?

Oral

11

What is characteristic of the oral route?

Absorption depends on GI tract secretion and motor function.

12

Tick the feature of the sublingual route

Pretty fast absorption

13

Pick out the parenteral route of medicinal agent administration

Inhalation, IV.

14

Parenteral administration

Usually produces a more rapid response than oral administration

15

What is characteristic of the intramuscular route of drug administration?

Oily solutions can be injected

16

True or False. Intravenous injections are more suitable for oily solutions.

FALSE.

17

True or False. Intravenous administration provides a rapid response

TRUE

18

True or False. Intramuscular administration requires a sterile technique

TRUE

19

True or False. Subcutaneous administration may cause local irritation

TRUE

20

True or False. Most of drugs are distributed homogeneously.

FALSE

21

Biological barriers include

- Cell membranes
- Capillary walls
- Placenta

22

What is the reason of complicated penetration of some drugs through brain-blood barrier?

Absence of pores in the brain capillary endothelium

23

The volume of distribution (Vd) relates

The amount of a drug in the body to the concentration of a drug in plasma.

24

For the calculation of the volume of distribution (Vd) one must take into account

Concentration of a substance in plasma

25

True or False. Small amount of the volume of distribution is common for lipophylic substances easy penetrating through barriers and widely distributing in plasma, interstitial and cell fluids.

FALSE

26

The term “biotransformation” includes

Process of physicochemical and biochemical alteration of a drug in the body.

27

Tick the drug type for which microsomal oxidation is the most prominent

Lipid soluble

28

True or False. Microsomal oxidation results in an increase of ionization and water solubility of a drug

TRUE

29

Stimulation of liver microsomal enzymes can

Require the dose increase of some drugs.

30

Metabolic transformation (phase 1) is

Transformation of substances due to oxidation, reduction or hydrolysis.

31

Biotransformation of a medicinal substance results in

Faster urinary excretion.

32

Conjugation

Coupling of a drug with an endogenous substrate

33

Which of the following processes proceeds in the second phase of biotransformation

Acetylation

34

Conjugation of a drug includes

- Glucoronidation
- Sulfate formation
- Methylation

35

True or False. Metabolic transformation and conjugation usually results in an increase of a substance biological activity

FALSE

36

In case of liver disorders accompanied by a decline in microsomal enzyme activity the duration of action of some drugs is

Enlarged

37

Half life (t ½) is the time required to

Change the amount of a drug in plasma by half during elimination.

38

Half life (t ½) doesn’t depend on

Time of drug absorption

39

Half life (t ½) depends on

- Biotransformation
- Concentration of a drug in plasma
- Rate of drug elimination

40

Elimination is expressed as

Clearance of an organism from a xenobiotic.

41

Elimination rate constant (Kelim) is defined by the following parameter

Half life (t ½)

42

True or False. The most rapid eliminated drugs are those with high glomerular filtration rate and actively secreted but aren’t passively reabsorbed

TRUE

43

Systemic clearance (CLs) is related with

Volume of distribution, half life and elimination rate constant.

Decks in Pharmacology Class (41):