Dermatology Flashcards
Topical Retinoids Examples
- Tretinoin/Retin-A - 1st gen
2. Adapalene/differin - 3rd gen
Oral Retinoids examples
isotretinoin/accutane - 1st gen
what are Retinoids?
vitamin A derivatives
special considerations with Accutane/Isotretinoin
- extremely teratogenic (category X) - causes craniofacial abnormalities, CNS structural malformations, cardiovascular abnormalities
- need to be part of iPledge program to prescribe and take - can only give 30 days at a time
- should avoid pregnancy for 3 years after acitretin is discontinued
general Retinoids MOA
increase growth factors –> causes epidermal hyperplasia and thickened skin –> subsequent desquamation and peeling of skin
Isotretinoin/Adapalene Indications
- acne
2. photoaged skin
Indications for retinoids in general
- acne
- photoaged skin
- severe psoriasis not responsive to other treatments
- cutaneous T cell lymphoma
Retinoids CI
- pregnancy - must have extensive conversation
2. tetracycline coadministration - risk of increased intracranial HTN
who are you most concerned about pseudotumor cerebri? how does it present?
- females, early adolescents to 20s - taking oral retinoids and tetracycline
- new onset headache and blurred vision
Retinoids MOA in acne
- decreases sebum secretion and sebaceous gland size
- reduces abnormal follicular epithelial differentiation and desquamation
- reduces comedogenesis (comedone is blackhead)
- reduces colonization of proprioibacterium
Retinoids MOA in photoaged skin
partial restoration of markedly reduced levels of collagen
instructions on how to take oral retinoids
- take with meals, fatty foods to increase absorption
2. take will full glass of water
Retinoids metabolism
liver
Retinoids SE
- mucocutaenous side effects
- cheilitis
- xeroderma
- skin peeling
- sicca (dry eyes)
- epistaxis - myalgias
- photosensitivity
- depression / changes in mood
- hyperostosis (excessive bone growth) after 5 years of treatment
Retinoids patient education
- side effect of dryness is common, would expect to see it
- combat w/ lip balm, vasaline, eye drops, sugarless candy, saline nasal spray
- may get worse before you get better
- don’t donate blood if taking oral isotretinoin
- pregnancy
Retinoids less common SE
- reversible increase in liver enzymes
- elevated cholesterol
- transient loss of color or night vision
Retinoids rare SE
- pseudotumor cerebri
- psychosis
- IBD
labs to do with isotretinoin
baseline LFTs and follow every 1-2 months
urine pregnancy test monthly
keratolytic examples
- alpha hydroxyl acids
- salicyclic acid
- benzoyl peroxide (mild) - Benzac
keratolytic MOA
break down keratin in skin
keratolytic indications
- acne (mild keratolytics)
- hyperkeratotic lesions - warts, psoriasis, eczema
- cosmetic - chemical peels
keratolytic CI
open wound
benzoyl peroxide MOA
oxidizes bacterial proteins and deceases anaerobic bacteria in follicles
keratolytic formulations
- cream
- ointment
- plasters
what percentage does salicyclic acid start to become destructive to tissue
6%
how to apply plasters
- apply for 4-5 days and then removed
2. occlusive dressing is commonly applied over topical agent to prevent it from being washed away, increases absorption
keratolytic SE
- local skin irritation - redness, itching, tenderness
- salicyclic acid toxicity (esp children)
- hyperpigmentation if high concentration
Topical steroid examples
- Betamethasone
2. Tramcinolone
Topical steroid indications
- psoriasis
- atopic dermatitis
- seborrheic dermatitis
- contact or irritant dermatitis
Topical steroid CI
active infection in skin (may cause impetigo)
Topical steroid MOA
anti-inflammatory effect, vasoconstrictive effect
- inhibits phospholipase A2 –> no arachidonic acid –> no prostaglandins or leukotrienes
areas on body with thinner skin
face, axilla, groin
Things that impact absorption of Topical steroid
- occlusive skin covering - increase
- inflammation - increase
- exfoliative skin - decrease
Topical steroid potency
- graded on scale from 1 to 7 with 1 being most potent
2. most use low, medium, high, very high potency
Topical steroid formulations
ointments, creams, lotions, gels, foam
general info/pros/cons of Topical steroid ointments
general - water suspended in oil, apply 2-3x per day after skin has been moistened
pros - greatest absorption, good for dry lesions b/c form water barrier (occlusive effects)
cons - greasy and not useful on hairy areas
general info/pros/cons of Topical steroid creams
semisolid emulsions in 20-50% water
pros - not greasy, easy to use if area is exposed or frequently touching
cons - less potent than ointments
general info/pros/cons of Topical steroid lotions
general - powder in water formulations
pros - useful in hairy areas and large areas, evaporate and provide cooling and drying effect so good for moist lesions
cons - least potent
general info/pros/cons of Topical steroid gels
general - oil in water emulsion w/ alcohol in base, liquify on contact with skin
pros - not greasy, useful for hair covered areas
general info/pros/cons of Topical steroid foams
general - pressurized collections of gaseous bubblies in liquid film
pros - spread readily, easy to apply
Topical steroid SE
- skin atrophy - w/in 2 weeks if high potency
- telangiectasia
- ecchymosis
- striae
- hypertrichosis (increased hair)
- redness
- pigmentation changes
Topical steroid systemic SE
- adrenal suppression
- Cushing’s syndrome
- Na retention
- HTN
- mood changes
- glaucoma
sites to use low potency steroids
face, genitals, axilla, neck
children!
duration goal or steroid treatment
<3 weeks
imiquimod / Aldara indications
- genital and perianal warts resistant to conventional therapy
- actinic keratosis
- basal cell carcinoma
imiquimod / Aldara MOA
- enhances immune system and stimulates response against abnormal skin cells
- increases release of interferon, TNF, interleukins
- activates macrophages, Langerhans cells
- induces proliferation and maturation of B lymphocytes
- enhances NK cell activity
imiquimod / Aldara CI
none
imiquimod / Aldara SE
- local skin reaction - burning, stinging, itching, redness, swelling
- long term skin reactions - pigmentation changes
- skin blistering, flaking, crusting, open sores
- systemic reactions - fatigue, diarrhea, flu-like symptoms, HA
next step if actinic keratosis does not respond to treatment with imiquimod / Aldara
biopsy to ensure no carcinoma
first line treatment for warts
- ablation ie. cryoablation using liquid nitrogen - apply for 10-20 seconds
5 characteristics that increase the probability that lesion is squamous cell carcinoma
- hyperkeratosis - raised
- full thickness
- surrounding induration
- surrounding erythema
- tenderness