Pharmacology

Question 1

What are the four stages of pharmacokinetics

Answer 1

Absorption
Distribution
Metabolism
Excretion

Question 2

How does albumin binding affect distribution

How does blood flow affect distribution

Answer 2

More albumin bound- harder to distribute

More blood flow= better distribution

Question 3

What is the definition of volume of distribution
How does molecular weight affect this
What does volume of distribution help calculate

Answer 3

The theoretical volume the drug would have to occupy to equate to plasma concentration

Higher molecular weight- more likely to be protein bound therefore less volume of distribution

Dosing (larger vD needs bigger dose to get concentration)

Question 4

What is bioavailability
What is it normally in IV drugs
How do you calculate bioavailability

Answer 4

The amount of unchanged drug reaching the circulation
100%
AUC (oral)/ AUC (IV) x100

Question 5

Elimination

What is the difference between first and zero order kinetics

Answer 5

First- a constant proportion of the drug is excreted in time. Depends on the concentration in the body.

Zero order- a constant amount is excreted over time. Not dependant on concentration

Question 6

How do you calculate half life

Answer 6

Volume of distribution/clearance

Question 7

How many half lives does it take to get to steady state
To prevent toxicity what do you want the steady state to do?
How can you achieve steady state more rapidly?
Which pharmacology principle contributes most to steady state

Answer 7

4-5
Be within therapeutic range
Loading doses
Clearance

Question 8

What type of drugs need to be metabolised by the liver before they can be Renally excreted?

What are the three processes in phase 1. What enzymes do they need

Answer 8

Lipophillic

Oxidation, reduction and hydrolysis
Cytochrome p450

Question 9

What are the two most common cytochrome p450s

Which is needed in codeine. What does a low analgesic response mean

Answer 9

CYP1A2
CYP34A4
CYP206- poor metabolism

Question 10

What are examples of p450 inducers. Give 5 p450 inhibitors

Answer 10

Phenobarbitone/ phenytoin, carbamazepine, alcohol, ridampicin, St. John’s wort

Grapefruit, erythromycin, cipro, cotrimox, amiodarone

Question 11

What are examples of processes seen in phase 2 liver metabolism

Answer 11

Acetylation, sulphination, glutathione production and glucuronidation

Question 12

What defines antibiotic tolerance

Answer 12

MBC>4x MIC

Question 13

What is the most important mechanism of the following antibiotics
Beta lactams
Aminoglycosides
Vancomycin

Give an example of a bacteriostatic antibiotic

Answer 13

MIC
Concentration dependant killing
Time dependent killing

Trimethoprim

Question 14

Which chemo acts on the following cell cycles 
G1 
S 
G2
m

Answer 14

G1 asparginase and prednisone
S methotrexate and 6MCP
g2 etoposide and bleomycin
M vincristine and vinblastane

Question 15

Which chemo causes radiation recall

Which causes extravasation injuries

Answer 15

Daunorubicin

Vincristine and doxyrubicin

Question 16

Which 2 chemo cause vomiting ++

Answer 16

Cisplatin

Cytarabine

Question 17

Which chemo causes fever

Answer 17

Cytarabine (araC)

Question 18

Which chemo causes anaphylaxis

Answer 18

Asparginase

Question 19

Which chemo causes pancreatitis

Answer 19

Asparginase

Question 20

Which antibiotic acts on the cell wall directly

Answer 20

Vancomycin

Question 21

Which antibiotics act on protein synthesis and how

Answer 21

Gent and tetracyclines- 30s

Macrolides and clinda- 50s

Question 22

Which antibiotics act on DNA synthesis and how

Answer 22

DNA gyrase- cipro
Folate- trimethoprim
RNA- rifampicin

Question 23

1mg pred= how much hydrocortisone

1mg dex=‘

Answer 23

4mg

25mg

Question 24

What are the main side effects of
Cyclosporine
Tacrolimus

Answer 24

Hirsuitism and gum hypertrophy

Alopecia, diabetes and low mg

Question 25

What does a clockwise hysteresis loop show? Anti-clockwise?

Answer 25

Tachyphylaxis | Delayed distribution

Question 26

How do the following diabetes meds work Metformin Glicazide Thiazolinedinedones

Answer 26

Increased sensitivity Increased production Increased sensitivity

Question 27

``` What MABs work on the following Terminal complement pathway Cd20 Interferon alpha Il 1 Il6 IgE ```

Answer 27

``` Ecilizumab Rituximab Infliximab/adalimumab Anakinara Tocilizumab Omalizumab ```

Question 28

What is the main mechanism of omeprazole

Answer 28

Serotonin antagonist

Question 29

``` What are the main side effects of Rifampicin Isoniazid Ethambutol Pyrazinamide ```

Answer 29

Orange secretions and liver toxicity Peripheral neuropathy and liver toxic Hepatitis esp with isoniazid Reduced colour vision

Question 30

What are the main side effects of the following AEDS Vigabatrin Topirimate Ethosuximide

Answer 30

Behaviours and ocular toxicity Renal stones and weight loss GI

Question 31

``` AED side effects Keppra Sodium valproate Lamotrigine Carbamazepine ```

Answer 31

Behavioural change and weight gain Pancreatitis low plt weight gain GI, liver and pancytopenia Liver and SJS

Question 32

Which chemo causes bad constipation

Answer 32

Vincristine

Question 33

Which two chemos cause secondary malignancies

Answer 33

Cyclophosphamide | Etoposide

Question 34

What are the three main steps in treatment of hyperkalaemia and what does each step do

Answer 34

1) give gluconate- stabilises the myocardium 2) give insulin/dextrose- moves it all intracellular 3) give resonium- reduces total body potassium

Question 35

How does MMF work | What are the three main side effects

Answer 35

Blocks purine synthesis Stops proliferation of b and T cells Diarrhoea vomiting and renal

Question 36

How does methotrexate work What are the main side effect What is a serious but rare side effect

Answer 36

Anti folate- reduces TNF alpha Ulcers mood changes Hepatitis

Question 37

What is the main cause of liver toxicity in paracetamol overdose

Answer 37

Conversion by CYP450 to NAPQI