Dermatology

Question 1

Epidermis

Answer 1

4-5 layers, primary barrier to drug absorption, drugs have to get to dermis to be absorbed, hypodermis (fat layer) has an affect on lipid soluble drugs

Question 2

Primary Barrier

Answer 2

Stratum Corneum- rate limiting step, hydrophobic

Question 3

Factors Affecting Drug Absorption

Answer 3

thickness, hydration, time, area of exposure, occlusion (more occlusion can help absorption like patch or plastic wrap) but have increased risk of bacterial growth, drug conc., size of molecule, age (hydration, thickness and sun sensitivity), temp and vasculature, cellular arrangement of skin

Question 4

Location (very important for exam)

Answer 4

best absorption in mucous membranes, hardest place is the palms of hands and feet

Question 5

Considerations of Vehicles

Answer 5

solubility, rate of release, increase hydration can increase absorption, stability of drug and chemical and physical interations

Question 6

Formulations

Answer 6

ointments are the best at stopping evaporation, tincutres and wet dressings are the best when you want a drying effect

Question 7

Topical Preps

Answer 7

lotions, gels, creams, ung, solutions, patches, advantages: longer steady state, prevent exposure to GI and bypass first pass metab.

Question 8

Lotions

Answer 8

scented lotions are more drying, for drying effects,

Question 9

Gels

Answer 9

non-greasy, cooling

Question 10

Aerosols

Answer 10

drying effects, don’t have to rub in, more expensive

Question 11

Powders

Answer 11

no need to rub in, can cake in wet areas (bad)

Question 12

Creams

Answer 12

drying effects, greasy

Question 13

UNG

Answer 13

good for hydration, not good for hairy areas

Question 14

Common ADE

Answer 14

irritation, pruritis, erythema, redness, contact dermatitis, Urticaria

Question 15

Topical ABX

Answer 15

prevent infection, deodorization, acne, single active ingredients or w/ corticosteroids or other ABX

Question 16

Bacitracin

Answer 16

Gram (+), and anerobes, ADE contact dermatitis, poorly absorbed, found in Neosporin, used to decrease colonization

Question 17

Polymixin B and Neomycin

Answer 17

Gram (-), many preparations, ADE contact dermatitis

Question 18

Bacitracin Formulations

Answer 18

Alone, w/ Polymixin B and in triple ABX ugn w/ neomycin

Question 19

Mupirocin

Answer 19

GRAM (+), impetigo, intranasal to decrease colonization

Question 20

Altabax

Answer 20

Retapamulin, use for impetigo

Question 21

Topicals for Acne

Answer 21

clindamycin, erythromycin, metronidazole, sodium sulfacetamide (absorbed, not to be used in pts w/ sulfa allergy) ADE: dryness, burning, irritation

Question 22

Retinoic Acid

Answer 22

Tretinoin = Vit A, 10% to circulation, can cause mild erythema and peeling, may worsen over the first 4-6 weeks, lesions clear in 8-12 weeks, can thicken the epidermis and remove fine lines and wrinkles

Question 23

Adapalene

Answer 23

Differin or in combo w/ benzoyl peroxide Epiduo, similar to tretinoin but less irritating

Question 24

Tazarotene

Answer 24

Tazorac, (acne)

Question 25

Azelaic Acid

Answer 25

Finacea- 6-8 weeks for full effect

Question 26

Benzoyl Peroxide

Answer 26

antimicrobial to P acnes. ADE irritation, redness, Can bleach hair and clothing

Question 27

Lotrisone

Answer 27

Betamethasone and Clotrimazole

Question 28

Powder

Answer 28

best for athletes foot, but otherwise mostly ineffective

Question 29

Topical Antivirals

Answer 29

for HSV 1 and 2, for cold sores, Abreva (docosanol), Zovirax 5%, Denavir 1% (penciclovir)

Question 30

Topical Immunomodulators

Answer 30

Protopic (tacrolimus) Elidel (pimecrolimus) Aldara (imiquimod), ADE: pruritis, superficial erosion, Black box warning for malignancies

Question 31

Ectoparasiticides

Answer 31

RID and NIX for head Lice, must use a nit comb, both OTC, RX: Ovide (malathion) and Lindane

Question 32

Scabes (transferred from skin to skin contact)

Answer 32

Elimite or Acticin (permethrin) drug of choice, leave on for up to 14 hours, Crotamiton lotion and Lindane are Legend RX

Question 33

Corticosteroids

Answer 33

``` Potency: Low-hydro, dexameth, betameth, TAC Med- hydrocor. val, desonide, High- fluocinonide, TAC Very High- clobetasol ```

Question 34

Counseling

Answer 34

don't occlude unless told otherwise, 1% systemic absorption, ADE: atrophy (wrinkled appearance), rosacea, drying, cracking, thinning, Cushing Syndrome

Question 35

Toical NSAIDs

Answer 35

for OA, acute pain, actinic keratosis, PHN when used along dermatome (Voltaren) diclofenac

Question 36

NDAID

Answer 36

less systemic absorption but still carry warning, don't use w/ oral NSAIDs, increased risk of thrombotic events, GI bleeding, pts undergoing CABG procedure