Derm Pharm Flashcards
Variables that affect rate of cutaneous absorption
region, concentration gradient, dosing schedule, vehicles/occlusion
Cream
half water/half oil with an emulsifier; spreads easily and well absorbed, best for oozing or wet skin conditions
Ointments
20% water, 80% oil; feel greasy and stay on surface of skin; best for dry skin because they trap moisture, allowing for more complete absorption of active ingredient
Single most important measure to reduce transmission of microorganisms to other areas of the body or patients
hand hygiene
Alcohol-based hand disinfectants are not effective against what bacteria?
C. difficile
Emolients
form an oily layer on top of skin that traps water in the skin
Common emolients
petrolatum, lanolin, mineral oil, and dimethicone
Humectants
draw water into the outer layer of the skin
Common humectants
glycerin, lecithin, propylene glycol
Horny substance softeners
loosen bonds between top layer of cells; helps dead skin cells fall off and skin retain water
Common horny substance softeners
urea, alpha hydroxy acids
Moisturizers for normal skin
water-based moisturizer that has a light, nongreasy feel
Moisturizes for dry skin
heavier, oil-based moisturizer that contains ingredients to keep skin dry
Moisturizers for oily skin
water-based product labeled “noncomedogenic”
Moisturizers for sensitive skin
sooth ingredients free of fragrances or dyes
Moisturizers for mature skin
oil-based moisturizer that contains petrolatum as the base to keep skin hydrated plus antioxidants
UVB radiation
280-320 nm, causes erythema/sunburn and skin aging and photocarcinogenesis
UVA radiation
320-400 nm, causes skin aging and cancer
Sunscreens
chemical compounds that absorb UV light
Sunscreen ingredients active in UVB range
PABA (p-aminobenzoic acid) and benzophenones
Sunscreen ingredients active in UVA range
dibenzoylmethanes
Sunshades
opaque materials that reflect light
Sun protection factor
ratio of minimal erythema dose without sunscreen to minimal erythema dose with sunscreen
Clorhexidine
broad-spectrum antimicrobial agent widely used due to general efficacy on skin and low irritability
Prions resistant to antiseptics and disinfectants
CJD
Protozoan resistant to antiseptics and disinfectants
cryptosporidium
Spores resistant to antiseptics and disinfectants
Bacillus ssp., C. difficile
Role of biofilms in abx reistance
limited penetration, abx neutralization
Is the use of antiseptic wash solutions necessary for wounds?
No, have minimal action against bacteria and may impede wound healing
Is the use of antibiotic therapy necessary for wounds?
Should only be used for wounds that appear clinically infected, no evidence that prophylactic use helps
How is glycemic control related to wound outcomes?
poor glycemic control is associated with worse outcomes
Typical reason for inadequate oxygenation of a wound
local vasoconstriction due to sympathetic overactivity
How does the removal of dead tissue and debris promote wound healing?
limits protease production and conserving local resources needed for healing
Role of low-pressure irrigation with normal saline for wound debridment
should be routine, flushes bacteria and removes loose material
Becaplermin
platelet derived growth factor that promotes cell proliferation and angiogenesis, black box warning for malignancy
General principles of wound dressing
wounds should be kept moist and not exposed to air, wounds can be exposed to their own fluid and improve healing
Wound dressing for debridement stage
hydrogel
Wound dressing for granulation stage
foam and low-adherence dressings
Wound dressing for epithelialization stage
hydrocolloid and low-adherence dressings
Bacitracin
abx that inhibits bacterial cell wall synthesis, active against G+ organisms, anaerobic cocci, neisseriae, tetanus bacilli, diphtheria bacilli; may cause contact dermatitis
Neomycin
binds to 30s subunit, active against G- organisms, can causes allergic contact dermatitis
Polymixin B
peptide abx that binds to phospholipids to alter permeability of membrane, effective against G-
Topical imidazoles
block ergosterol synthesis
Use for miconazole
vulvovaginal candidiasis
Use for clotrimazole
vulvovaginal candidiasis
Use for efinaconazole
onychomycosis
Use for ketoconazole
seborrheic dermatitis
AE of topical imidazoles
stinging, pruritis, erythema, local irritation
Ciclopirox
broad=spec topical antimycotic agent that disrupts macromolecular synthesis; active against dermatophytes, Candida, and Malassezia
Terbinafine
allylamine that selectively inhibits squalene epoxidase, a key enzyme for ergosterol synthesis; less active against yeasts
Tolnaftate
distorts hyphae and stunts growth; effective against various dermatophyte and Malassezia infections, not Candida
Nystatin
alters membrane permeability, topical treatment used for candida infections (swallowed or cutaneous)
Amphotericin B
alters membrane permeability, topical treatment for candida infections
Acyclovir
Inhibitory activity against HSV 1 and 2, used for herpes labialis
Nonpharmacologic interventions for pruritus
skin moisturization, cool environment, avoidance of irritants, stress reduction
Potency of topical steroid treatment
Use low-potency on face, genitals, skin folds; use high potency elsewhere and titrate down
Capsaicin
used for chronic pain and pruritis, activation of TRPV1 stimulates neurons to release and deplete neuropeptides to induce lasting desensitizations
Salicylic acid
COX inhibitor, found in many skin-care products; causes epidermal cells to shed more readily, keratolytic effects
Systemic therapies for pruritis
antihistamines, antidepressants, anticonvulsants
Brimonidine
alpha 2 adrenergic agonist, topical gel causes vasoconstriction
Oxymetazoline
mixes alpha 1 and alpha 2 adrenergic agonist, cream causes vasoconstriction
Malathion
topical organophosphate cholinesterase inhibitor used to kill ectoparasites
Permethrin
topical agent that binds to insect Na channels
Ivermectin
administered orally, binds to glutamate-gated Cl- channels in invertebrates hyperpolarizes nerve and muscles
lindane
topical agent that disrupts GABAergic transmission in insects
First drug choice for comedonal acne
Topical retinoid
First drug choice for mixed and papular/postural acne
topical retinoid and topical antimicrobial
First drug choice for nodular acne
oral abx, topical retinoid, BPO
First drug choice for severe nodular/conglobate acne
oral isotretinoin
Most common topical retinoid
Tretinoin
Common topical antimicrobials
benzoyl peroxide, clindamycin, erythromycin
Azealic acid
dicarboxylic acid, involved in plant defense response to an infection; kills acne bacteria and decreases production of keratin
Common oral abx used for acne
tetracycline, doxycycline, minocycline, erythromycin, azithromycin, TMP-SMX
Hormonal agents used for acne
oral contraceptives, spironolactone
AE tretinoin
local skin irritation, dryness, flaking, sun sensitivity
AE benzoyl peroxide
local skin irritation
AE clindamycin
pseudomembranous colitis
AE tetracycline
photosensitivity, GI distress
AE doxycycline
photosensitivity, GI distress
AE minocycline
dizziness, drug-induced lupus, skin discoloration
AE erythroycin
GI distress
AE azithromycin
GI distress
TMP-SMX
Stevens-Johnson syndrome, toxic epidermal necrolysis
Retinoid MOA
Increased transcription RARE ? , reduced follicular occlusion and microcomedone formation
Home skin care recommendations
synthetic detergent cleanser with warm water twice daily, antimicrobial soaps not recommended; water-based lotions, cosmetics and hair products
Initial topical therapies for psoriasis
emollients, corticosteroids
Topical therapies for psoriasis
topical vitamin D analogs, tar, tazarotene, anthralin, salt water bath
UV light therapy for psoriasis
UVB radiation to point of erythema 3x per week; PUVA penetrates deeper into the skin without causing sunburn
Systemic therapies of psoriasis
methotrexate, apremilast, retinoids, systemic calcineurin inhibitors, biologic agents
Apremilast
PDE4 inhibitor used for psoriasis, increases cAMP, decreases inflammatory mediators
Ustekinumab
IL-12 and IL-23 mAb for psoriasis
Secukinumab and Ixekuzumab
IL-17A mAb
Clinical applications apremilast
moderate to severe plaque psoriasis, active psoriatic arthritis
Administration of apremilast
orally
AE apremilast
severe diarrhea, nausea, and vomiting; HA, depression, suicide
Clinical applications ustekinumab
plaque psoriasis, Crohn disease, psoriatic arthritis
Administration of ustekinumab
subQ
AE ustekinumab
increases risk for infections and squamous cell carcinoma
Clinical applications secukinumab
ankylosing spondylitis, plaque psoriasis, psoriatic arthritis
Administration of secukinumab
subQ
AE secukinumab
increases risk for infection
Treatment options for actinic keratosis
liquid nitrogen cryotherapy, surgical therapy, 5-fluorouracil, immiquiod, red light therapy, dermabrasion, chemical peels
Topical 5-fluorouracil
inhibits thymidylate synthetase, enzyme in DNA synthesis; causes inflammation and dectruction of lesions
Skin progression for topical 5-fluorouracil
erythema through blistering, necrosis with erosion, re-epithelialization
Treatment of basal cell or squamous cell carcinoma
surgical removal/ablation, topical medications, vismodegib
Treatment of melanoma
surgical excision, dacarbazine with carmustine and tamoxifen OR cisplastin and vinblastine; vemurafenib
Minoxidil
vasodilation, K channel opening; promotes hair growth by increasing duration of growth phase, shortening rest phase, enlarging miniaturized follicles
Fenasteride
Oral inhibitor of DHT (dihydrotestosterone), increases hair count
Treatment of alopecia in men
minoxidil, fenasteride, surgery
Treatment of alopecia in women
minoxidil, spironolactone, finasteride, flutamide
Management of alopecia areata
chronic, relapsing immune-mediated inflammatory disorder affecting hair follicles resulting in non-scarring hair loss; treat with corticosteroids, topical immunotherapy
