Pharmacology & Drugs

Question 1

What is it thought paracetamol inhibits the release of?

Answer 1

COX-3

Question 2

What are the 2 route by which paracetamol is broken down?

Answer 2

98% - Glucuronic & sulphuric acids

2% P450 enzymes

Question 3

What is the toxic substance produced by the P450 enzymatic breakdown of paracetamol?

Answer 3

NAPQ1

Question 4

What is NAPQ1 deactivated by?

Answer 4

Glutathione

Question 5

What is the maxium dose of paracetamol for an average adult in 24hours?

Answer 5

4g.

Question 6

What is the half life of paracetamol?

Answer 6

2-4 hours in a health individual

Question 7

What is the half life of a drug?

Answer 7

the time taken for drug plasma concentrations to half

Question 8

In linear Pharmacokinetics how many half lives does it take to clear a drug?

Answer 8

4-5

Question 9

What does Pharmacokinetics involve?

Answer 9

Administration
Distribution
Metabolism
Excretion

Question 10

Whats the biggest difference between enteral and parental administration?

Answer 10

Parental by-passes liver metabolism

Question 11

What is the bio-availability of a drug?

Answer 11

The percentage of the drug that enters systemic circulation

Question 12

What is volume of distribution?

Answer 12

The apparent volume of drug in a given amount of plasma. The drug dose must first be known. - “If i give this much, how much will be in blood plasma of a given volume”

Question 13

What is drug clearance?

Answer 13

The theoretical amount of drug eliminated from plasma/ unit time

Question 14

What are the THREE mechanism by which bacteria use to be resistant to antibiotics?

Answer 14

Mutation of target site
Inactivating enzymes - Beta Lactase
Limiting access - increased reflux of the antibiotic

Question 15

What are the THREE main ways antibiotics are used?

Answer 15

Guided therapy
Empircal Therapy
Prophylactic therapy

Question 16

What kind of antibiotics are used in guided therapy?

Answer 16

narrow spectrum

Question 17

What kind of antibiotics are used in empirical therapy?

Answer 17

Broad spectrum

Question 18

What are ideal characteristics are wanted in antibiotics?

Answer 18

Highly toxic to bacteria
Able to easily access the required area in the body
Able to neutralise the toxins of the bacteria
Easily Administered
Limited co-lateral damage to the patient
Limited damage to comensal bacteria

Question 19

What are the Four main target areas of antibiotics?

Answer 19

Peptoglycan wall - Penicillin, glycopepitides
DNA - quinolones
Ribosomes - Macrolides, Aminoglycosides
Metabolism - Trimethoprim

Question 20

How do Beta lactams works?

Answer 20

The structure of the Beta lactam is almost identical to the final structure of the peptoglycan wall synthesis - called the transpepidase protein - thus inhibiting cross linking of the peptides

Question 21

What resistance is present to beta lactams?

Answer 21

Mutations in penicilin binding protein
Change in porins allowing access to the bacteria
Productions of beta lactamases

Question 22

What can be given in combination with penicillin to inhibit beta lactamases?

Answer 22

Beta lactamases inhibitors - co-amoxiclav

Question 23

Example of a glycopeitides?

Answer 23

Vancomyocin

Question 24

What is vancomyocin used to treat and what can’t it treat and why?

Answer 24

MRSA.

it can’t treat gram-negative because it can’t cross cell membranes

Question 25

What are common/ dangerous sides of Beta Lactams?

Answer 25

``` Type I hypersensitivity reactions Type IV - this is dangerous and delayed Diarrhea Liver dysfunction Secondary infection - C.Diff, Thrush ```

Question 26

What are macrolides useful for?

Answer 26

They are good at entering cell, therefore if there is a bacterial infection intraceullular infection they are useful. Used alot in upper respiratory infections

Question 27

What is used to break down Macrolides?

Answer 27

CYP 3A4

Question 28

What do Aminoglycosides inhibit?

Answer 28

30S ribosomes, inhibiting protein synthesis

Question 29

Abatacept function?

Answer 29

Blocks T cell activation

Question 30

Tocilizumab function?

Answer 30

Blockage of IL-6

Question 31

What is the loading dose?

Answer 31

The initial dose giving to bring the concentration up the therapeutic dose

Question 32

What is the loading dose calculation?

Answer 32

Volume of distribution x target concentration

Question 33

What is the maintenance dose?

Answer 33

The dosing to keep the wanted concentration constant

Question 34

what is the maintenance dose calculation?

Answer 34

Clearance rate x target dose

Question 35

If a drug has a low volume of distribution, will more or less drug be needed and why?

Answer 35

less - because more remains in the plasma as opposed to other compartments

Question 36

What is Emax?

Answer 36

It is the maximum efficacy of the drug - its maximum stimulus. we presume the receptors are fully saturated here.

Question 37

What is E50? and how does it relate to potency?

Answer 37

The concentration that the drug is at when it reaches half its maximum efficacy (Emax). the lower the E50 the more potent the drug as it reaches a the stimulus at lower concentrations

Question 38

Give an example of a bacterial-static antibiotic.

Answer 38

Clarithromyocin

Question 39

What antibiotic would cause the adverse effect of red man syndrome?

Answer 39

Vancomyocin

Question 40

What are the two beta lactamase inhibitors that be co-given with antibiotics?

Answer 40

Clavulanic acid Tazobactam

Question 41

Name a reversible Nicotine receptor antagonist

Answer 41

Atracurium