Pharmacology

Question 1

What are the 3 major route for medications?

Answer 1

Topical
Transdermal
Subcutaneous

Question 2

What does the stratum corneum consist of?

Answer 2

Corneocytes and intracellular lipids

Question 3

What is the structure of the stratum corneum like?

Answer 3

Bricks (corneocytes) and cement (intracellular lipids)

Question 4

What substances does the stratum corneum allow to pass through it?

Answer 4

Small, hydrophobic

Question 5

What does Fick’s Law calculate and what is the equation?

Answer 5

Rate of absorption

J = Kp Cv

Question 6

In Fick’s Law what do these letter stand for ?
K
C
J

Answer 6

K = permeability coefficient 
C = concentration of the drug vehicle 
J = flux

Question 7

What can improve partitioning?

Answer 7

Hydration of the skin

Inclusion of exipitents

Question 8

What are the 4 categories of topical steroids?

Answer 8

Mild
Moderate
Potent
Very potent

Question 9

What potency category is 1% Hyrdrocortisone acetate?

Answer 9

Mild

Question 10

What two vessels do drugs given subcutaneously reach by diffusion?

Answer 10

Capilleries

Lymphatics

Question 11

Disadvantage of giving drugs subcutaneously?

Answer 11

Injection volume limited

Question 12

Advantages of giving drugs subcutaneously?

Answer 12

Absorption slow 
Route for many protein drugs e.g. insulin 
Route for oil bases drugs e.g. steroids
Can give slow release over time 
simple
painless

Question 13

How are transdermal drugs applied?

Answer 13

Through adhesive patch placed on epidermis. Occurs through diffusion

Question 14

What factor make certain drugs most suitable for transdermal appliance?

Answer 14

Low molecular weight
moderately lipophilic
potent
relatively short half life

Question 15

Advantages of transdermal appliance?

Answer 15

Steady rate of drug delivery 
Decrease dosing frequency 
Avoidance of first pass metabolism 
Rapid termination 
User friendly 
Convenient and painless

Question 16

Disadvantages of transdermal appliance?

Answer 16

Relatively few drugs suitable
Allergy
Cost

Question 17

What drugs are given transdermally?

Answer 17

Nicotine
GTN
Fentanyl
Estradiol

Question 18

What are the advantages of using topical treatments?

Answer 18

Direct application of to area of treatment

reduce systemic effects

Question 19

What are the disadvantages of using topical treatments?

Answer 19

Time consuming
Correct dosage can be difficult
Messy to use

Question 20

Oinments have bigger risk of infection than creams, why?

Answer 20

Creams have added preservatives and ointments do not

Question 21

What topical treatments for good for the scalp?

Answer 21

Lotions

Question 22

What might pastes be used for?

Answer 22

Soothing/Cooling bandages for eczema that itches at night

Leaking from stoma or ulcer that is damaging the skin around it

Question 23

What are the 3 main modes of action of topical steroids?

Answer 23

Vasoconstrictive
Anti-inflammatory
Anti-proliferative

Question 24

How much is a finer tip unit?

Answer 24

1/2 g

Question 25

Side effects of topical steroids?

Answer 25

``` Thinning of skin (leads to stretch marks) Purpura Immunosuppression Steroid rosacea Fixed telangectasia Perioral dermatitis Tachyphylaxis (decrease response to effects) Rebound flare of disease ```

Question 26

What topical antibiotics are used to treat acne?

Answer 26

Clindamycin Erythromycin Tetracycline

Question 27

What topical antibiotics used to treat rosacea?

Answer 27

Metronidazole

Question 28

What topical antibiotic used to treat impetigo?

Answer 28

Staph --> Flucoxacillin | Strep --> Penecillin V

Question 29

What topical antibiotics used to treat infected eczema?

Answer 29

Combined corticosteroids/antibacteria

Question 30

What are keratolytics and what are they used to treat?

Answer 30

used to soften keratin e.g. salicylic acid 10-40% Viral wars Hyperkeratotic eczema, psoriasis Corns and calluses Thick plaques on scalp

Question 31

How to treat warts?

Answer 31

Mechanic paring and... ``` Keratolytics Fromaldehyde Glutaraldehyde Silver nitrate Cryotherapy (liquid nitrogen) Podophyllin (genital warts) ```

Question 32

What are the topical psoriasis treatments?

Answer 32

Emollients e.g. ``` Coal tar Vitamin D analogue Kerolytics Topical steroids Dithranol ```

Question 33

Bad side effect of Dithranol?

Answer 33

Can only be put on affected part of skin, if put on surrounding normal skin acts as an irritant and scars

Question 34

Side effect of Vitamin D analogues?

Answer 34

Can be an irritant