Dermatology Therapeutics Flashcards
in general, what is the most common therapy used in dermatology?
topical
creams, gels, lotions, powders, sprays, foams
Since the skin’s role is mainly as a barrier to outside sutbstances, what is drug delivery dependant on?
- skin type (thinner skin easier than thicker skin)
- Skin condition (inflamed, cracked, broken skin will more readily take up med)
- Lipid vs. water-based vehicle
- charge
- concentration gradient
What layer of skin is the “rate limiting step” to topical therapy absorption?
stratum corneum
How can we increase the penetrance of a topical med?
Hydrate the skin first
use a vehicle with higher occlusiveness and absorption - ointments better than creams, creams better than lotions, lotions better than gels, etc..
What are the actions of corticosteroids?
anti-inflammatory
immunosuppressive
anti-proliferative
vasoconstrictive
What are some of the dermatological uses for corticosteroids?
eczema, contact dermatitis, psoriasis, lichen planus
What are the adverse effects of corticosteroids?
skin atrophy (especially over thing skin like the groin)
striae
acne
suppression of the HPA axis
How are corticosteroids classified by strength?
1 to 7 with 7 being the mildest
based on standardized lab vasoconstriction assay
What are retinoids and what do they do?
vitamin A analogs
bind to nuclear receptors on DNA and alter gene transcription to regulate cell growth, inhibit carcinogenesis and alter enzymes involved with cellular differentiation
What are three topical retinoids?
- tretinoin (retin-A)
- tazarotene (tazorac)
- adapalene (differin)
What are the uses for retinoids?
acne
psoriasis
cosmetic skin improvement (wrinkles)
What is the main side effect of the retinoids?
dry skin
irritation
sun sensitivity
Specifically what type of acne responds well to retinoid use?
comedonal acne
What is Calcipotriene?
a vitamin D analog that acts through DNA receptors to alter skin differentiation (similar to the retinoids)
(also called Dovonex)
What is calcipotriene used for?
psoriasis
WHat are the 2 side effects of calcipotriene?
irritation and increased serum calcium
What are some topical antimicrobials we use?
clindamycine or erythromycin gel
benzoyl peroxide gel
tervinafine, oxiconazole (antifungals)
metronidazoles gel (for rosacea!)
bacitracin or mupirocin (on wounds)
What do topical calcineurin inhibitiros (TCIs) do?
they are considered the nonsteroidal anti-inflamatory drugs
they work through calcineurin to alter T-cell activation, so they’re good for T-cell mediated diseases like contact dermatitis
What are two TCIs we talked about?
tacrolimus (protopic)
pimicrolimus (Elidel)
On what part o the body would you want to use a TCI?
On thin skin where it’s better to avoid the steroids
like the eyelids and groin
in terms of sunscreens, which ones actually BLOCK the sun?
the metals -
titanium dioxide and zinc oxide
What ist he lowest SPF that can claim reducing skin cancer risk?
SPF 15
What term on a sunscreen bottle will mean they cover UVA and UVB?
broad spectrum
How does Imiquimod (Aldara) cream work?
It’s an immune response modifier that actually INCREASES inflammation
through toll-like receptors
What do we use imiquimod (aldara) for?
warts
actinic karatosis
BCC (in situ)
molluscum
What other topical drug can be used in the same situations as Imiquimod?
topical 5-fluorouracil
What will happen to Aktinic keratoses during treatment with either imiquimod or 5-FU?
THey will get WORSE before they resolve because it’s bringing in the immune response
Current research suggest what for wound care?
We should keep it covered with a nonstick dressing to allow natural cytokines to facilitate healing
monitor for infection
airing out wounds slows healing and increases likelihod of scarring
What are the systemic retinoids?
- isotretinoin (accutane, sotret ,amnesteem, claravis)
- acitretin (soriatane)
What are the main concerns with systemic retinoid use
dryness
hyperlipidemia
teratogenicity (have to be on birth control)
hepatitis
hair loss
depression?
So in labs you need to monitor lipids, liver function and pregnancy
What might we use systemic retinoids for?
acne
psoriasis
ichthyosis (“fish skin” issue with holding on to keratinized cells too long)
What does Dapsone (sulfone) do?
inhibits myeloperoxidase in neutrophils with an affect on CD11a and CD18
so we use it for diseases that are neutrophil rich
What conditions do we use Dapsone for?
dermatitis herpetiformis
linear IgA disease
bullous lupus
Sweet’s syndrome
spider bites
any neutrophilic skin diagnosis
What are the main concerns with dapsone?
can cause hemolysis especially in people with G6PD deficiency
ALso methemaglobinemia and motor neuropathy
so check CBC and G6PD in labs
How does methotrexate work?
it’s a dihydrofolate reductase inhibitor that disrupts DNA synthesis
also immunosuppressive
What do we use methotrexate for?
psoriasis
CTCL
lupus
What are the concerning side effects of methotrexate?
hepatotoxicity (so check LFT -live biopsy?)
myelosuppression (so check CBC)
pneumonitis
The newest generation of systemic therapy for psoriasis psoriatic arthritis, and RA are what? How do they work?
the biological therapies
they are biogenetically engineered proteins that disrupt focused portions of the immune system involved in psorasis
have fewer side effects!
What are some of the biological therapies?
Amevive - inhibit T memory cells
Enbrel - inactivates TNF
Remicade (inhibits TNF and some cytokines)
Humira (inhibits TNF)
Stelara (binds to p40 subunit of IL-12 and IL-23)
WHat does UV light therapy do?
It forms pyrimidine dimers in DNA and reduces langerhans cells and leukocytes - thus it’s anti-inflammatry and immunosuppressive
What are the 3 versions of UV light therapy?
UVB
Narrow band UVB (less likely to burn or cause cancer)
PUVA (Psoralen plus UVA)
What are the uses for UV light therapy?
psoriasis
pruritus
eczema
CTCL
WHat is Minoxidil? What is it used for?
It’s Rogaine!
Is acts through vasodilation and direct stimulation of hair shaft growth
Used for alopecia
What is Finasteride? What is it used for?
Finasteride = Propecia
It blocks the 5-alpha reductase enzyme in follicles to inhibit the conversion of testosteorn to diydrotesterone.
This works better for androgenetic alopecia than minoxidil
What do we use liquid nitrogen for?
it freezes tissue of warts, actinic keratoses, small skin cancers
In moisturizers, what do the following do?
Occlusives?
Humectats?
Emollients?
Occlusives trap moisture in
humectants bind water
emollients give skin a smooth feel
We don’t we like soaps for cosmetic products?
they are made from animal fats and have a negative charge, thus they tend to strop of fnatural skin barrier of lipids resulting in drying.
minimize their use and use non-soap cleansers like Purpose
What are alpha hydroxy acids used for?
cosmetic effects
they exfoliate, thicken epidermis, stimulate collagen growth and increase skin profusion
this results in fewer wrinkles, more pliable skin and better hydrations
this is what’s used in chemical peels
What is alopecia?
hair loss
What is pediculosis?
lice infestation
How do scarring and nonscarring alopecias differ?
scarring is usually due to an inflamatory process whereas nonscarring is more do to poblems with the hair growth cycle itself (anagen, catagen, telogen)
Describe androgenetic alopecia.
this is the simple baldness, hereditary alopecia, or pattern alopecia
it’s nonscarring
It’s caused by genetically determined miniaturization of follicles triggered by androgens
More on the top of scalp
More sommon in males, but also in women soemtimes (men tend to get it earlier)
Treat with minoxidil or finasteride
What is telogen effluvium?
It’s stress hair loss
nonscarring
you get distrupted growth cycle of hairs causing a premature shift from anagen to telogen and the hair falls out in clumps
triggered by pregnancy, surgery, high fever, extreme diet, etc.
What is the treatment for relogen effluvium?
Once the trigger is removed, it just takes time and reassurance
What is alopecia areata?
It’s an autoimmune disease where T-cells attack the hair bulbs
You lose circular pathces on the scalp or beard (can end up losing all the hair on the scalp or even on the entire body)
What are the treatment options for alopecia areata?
It’s difficult
watch and wiat first, then you can use topical or IL steroids
Try minoxidil
What is secondary alopecia?
It’s diffuse hair thinning as a complication of an existing mediation or medical problem
often from chemotherapy meds, thyroid problems, iron deficiency, nutritional disorders, renal/hepatic failure
What is the most common cause of tinea capitis?
Who is affected most often?
trichophyton tonsurans
african american kids
What is the standard treatement for trichophyton tonsurans?
oral griseofulvin
also terinafine or itraconazole
What are the two general forms of pediculosis?
pediculus humanus capitus (head lice)
Pthirus pubic (pubic lice)
What are the treatment options for pediculosis?
permethrin (Nix or elimite)
Malathion
Vaseline (for eyelids)
Cetaphil cleanser
remove the nites
HOT water and dryer for clothes and bedding.
Put unwashables in a bag for 2 weeks
What is paronychia?
inflammation of the nail folds
can be infectious or noninfectious
How can you avoid/treat ingrown nails?
always cut nails straight across
don’t tear of pull them
wear proper fitting shoes
soak them
take antibiotic if infections
surgery if necessary
What is onychymycosis?
fungal growth on or under the nail
What are the common organisms for onychomycosis?
trichophyton rubrum
trichyphyton mentagrophytes
(diagnose with nail clipping cultures)
What is the best way to treat onchymycosis?
oral tervinafine or itraconazole
