Pharmacology (General)

Question 1

The stratum corneum
The Bricks are …
The Mortar is….

Answer 1

flatted dead cells (corneocytes)

multiple bilayer of lipids in plate like structure

Question 2

water and lipids dont mix t/f

Answer 2

t

lipid r hydrophobic

Question 3

Two routes of crossing stratum corneum?

Answer 3

transcellular

intercullalr

Question 4

wHAT INFLUENCES DIFFUSION

Answer 4

HOW PERMEABLE
CONCENTRATION
HOW MUCH HAS TO CROSS

Question 5

VEHICLE DOES NOT INFLUENCE RATE AND EXTEN OF ABSORP t/f

what factors affect?

Answer 5

f (permiability,concentration, solb)
vehicle dictates permeability and conc (with regards to crossing stratumn corneum)

Drug solubility in vehicle important and is dictated by vehicle

Question 6

Lipophilic drug in hydrophilic base will diffuse across the stratum corneum …. and diffuse into blood stream …..

Answer 6

lots, lots
like attracts like, hydropgilic base will stay on stratum corneum and repel the lipophilic drug into the mortar of the skin

Question 7

Lipophilic drug in lipophilic base will diffuse across the stratum corneum …. and diffuse into blood stream …..

Answer 7

moderately, moderately

Question 8

hydrophillic drug in hydrophilic base will diffuse across the stratum corneum …. and diffuse into blood stream …..

Answer 8

not at all, not at all

Question 9

hydrophilic drug in Lipophilic base will diffuse across the stratum corneum …. and diffuse into blood stream …..

Answer 9

a tiny bit, a tiny bit

Question 10

When drugs are applied topically only the soluble fraction provides the driving force for absorption
t/f

Answer 10

t

Question 11

Physical and chemical factors that can influence how readily the drug disassociates from the vehicle?

Answer 11

Hydratig the skin (prevents water loss)
Choose the right vehicle (ointments over some creams)

Site of application

Integrity of skin (trauma, inflammation)

Question 12

Decreased partitioning results from a reduction in the barrier function of the stratum corneum
t/f

Answer 12

F

increase partitioning

Question 13

Describe molecular mechanism of glucocorticosteroids

Answer 13

1) Glucocorticosteroids diffuse across lipophilic cell membrane
2) Bind to receptor GR2a and activates it
Heats shock proteins disassociate from GR2a receptor
GR”a and glucocorticosteroid translocate to nucleus and form homodimers
3) Bind to glucocorticoid receptor elements on promoter region of DNA
Results in transcription of certain genes switched. Less mediator proteins, less synthesis rate.

Question 14

Subcutaneous route of administration?

Answer 14

Drug delivered by a needle into adipose tissue just beneath epidermis

Question 15

Advantages of subcutaneous route?

Answer 15

Slow absorption due to less circulation in adipose tissue

Can be used to introduce a depot of drug under the skin that is slowly released into circulation

Question 16

Subcut administration is used for many …. drugs, such as insulin and many …. based drugs such as steroids

Answer 16

protein, oil based

Question 17

Skin is a good route because?

Answer 17

Avoids first pass metabolism
Avoids potential toxicity of drugs to organs such as liver
Simple and non sterile (topical application)
Allows for steady state plasma conc to be achieved (slow release)

Question 18

Skin bad route because?

Answer 18

Only limited drugs diffuse across epidermis

Question 19

How does TDD work?

Answer 19

Drug accumulated in adhesive patch and diffuse across cutaneous barrier

Question 20

TDD can only be used topically t/f

Answer 20

F can be used to treat systemic disease

Question 21

TDD is most suitable for drugs that are.. (4)

Answer 21

1 low molecular weight
2 moderately lipophilic
3 potent
4 brief half life

Question 22

Chemical enhancers of TD interact with ….. to increase permeability mainly to drugs that can already ……

Answer 22

lipid matrix, cross skin reasonably well

Question 23

Chemical enhancers of TDD do not have an issue with irritation/toxicity t/f

Answer 23

F they do

Question 24

Chemical enhancers of TDD are highly effective for highly water soluble drugs or macromolecules

Answer 24

F

they are NOt HIGHLY effective for highly waater soluble drugs, mostl work for drugs that lipophilic

Question 25

agents for chemical enhancers of TDD include ...... - this creates a 'pore' pathway and causes prolonged occlusion ........., such as ehthanol ........., such as sodium dodecyl sulphate

Answer 25

water, solvents, surfactants

Question 26

Management of itch?

Answer 26

1) Treat CAUSE (ONDANESTRON opiate antagonist - buildup causes itch in liver problems, anti epileptics for certain neurogenic causes of itch) 2) Anti itch ttreatment - anti histamines - cooled emollients - antidepressants - phototherapy (dampens immune response)

Question 27

``` Mild: Moderate: Potent: Very potent: (mometasone, hydrocortisone, clobetasol,modrasone) ```

Answer 27

Mild: Hydrocortisone Moderate: Modrasone Potent: Mometasone Very potent: Clobetasol

Question 28

Side effects of topical corticosteroids?

Answer 28

- Thinning of skin - Purpura - Stretch marks - steroid rosacea - fixed telangectasia - Perioral dermatitis - May mask infections - Tachypulaxis: decrease in response to anti-inflammatory effects - rebound flare disease (body stops producing own steroids)

Question 29

What is an example of an antipuritic?

Answer 29

Menthol lotion | Capaicin - reduces neural transmission from red chilli peppers

Question 30

An example of a keratolytic? Where is it used?

Answer 30

Used for viral warts, hyperkeratotic eczema and psoriasis, corns SALICYLIC ACID

Question 31

Dithranol works how? Used where? Disadvantages?

Answer 31

Slows cell replication Stable chronic plaque psoriasis Messy and smelly

Question 32

Vitamin D analogue works how? Used where? Pros and cons?

Answer 32

Affects rate of cell division Stable chronic plaque psoriasis Can be irritant. Clean no smell, easy to apply

Question 33

Coal tar works how? Used where? Disadvantages?

Answer 33

antiinflammatory Stable chronic plaque psoriasis Messy and smelly

Question 34

Treatment for scalp psoriasis?

Answer 34

Greasy ointments to soften scale Tar shampoo Steroids in alcohol base or shampoo Vitamin D analogues

Question 35

Wet wrap therapy?

Answer 35

``` This is used for very dry (xerotic) skin with mosituriser, cooling and soothing. prevent scratch aply paste time consuming ```

Question 36

Indications for topical corticosteroids?

Answer 36

Eczema Psoriasis (eg flexures) Beware rebound, triggering pustular psoriasis) Other non-infective inflammatory dermatoses e.g. lichen planus Keloid scars (usually intralesional)

Question 37

Tacrolimus and pimecrolimus are examples of?

Answer 37

Calicneurin inhibitors

Question 38

Calcineurin inhibiter work how? When and for what? Risks and cons?

Answer 38

Suppress lymphocyte activation. Second line treatment eczema Risk infection and skin cancer? burning sensation on application

Question 39

Antiseptics indicated for? Examples?

Answer 39

Recurrent infections Antibiotic resisistance Wound irrigation Triclosan, hydrogen peroxide

Question 40

Treatment for shingles?

Answer 40

Treat with acyclovir 800mg 5 times daily for 7-10 days Tramadol for 4 days Local cooling agents

Question 41

Dermatitis herpetiformis lab confirmation? What condition is associated w dermatitis herpetiformis?

Answer 41

IGA anti tissue transglutaminase and FBC | celiac disease