75: Dermatology Flashcards
When to refer skin
-multiple/extensive burns, cuts, abrasions
-human/animal bites
-bad rash
-tumors/growths
-yellow skin
-deep infection (cellulitis)
-large blisters of unknown origins
-exposed deep tissue, muscle, bone
Choosing a base for skin tx
- desired effect
- area of application
- patient acceptability
- nature of incorporated medication (stability, compatibility)
Basic vehicles for most skin rx
-ointment
-cream
-lotion gel
-solution/foam/spray
Ointments
-best for hydration and drug delivery
-removes scales
-greasy, low acceptance, no good for hairy areas
Creams
-good for hydration and drug delivery
-can apply to most areas
-high acceptance
Lotions
-watered down creams
-easy to apply
-good acceptance
-requires freq applications
-not ideal for very dry skin
Gels
-great for alcohol soluble drugs
-can apply to most areas
-nongreasy
-can be drying
Solutions, foams, sprays
-can apply to most areas
-easy to apply in hairy earea
-not ideal for drug delivery
-can be drying
-not ideal for hydration
-requires freq application
best vehicles for hair bearing skin
-solution/spray
-foam
-gel
-cream
Dry Skin (xerosis)
-fall and winter
-feet, lower legs
-hands, elbows, face
-rough, dry, scales, cracks
-itching common
Who is at risk of dry skin (xerosis)
-elderly
-dec activity of sweat and sebaceous glands
-warm, dry environments
-freq bathing
Dry skin (xerosis) tx
- emollients
- agents for itching
- alter bathing habits
Rule of 3s
-bathe no more than 3x week
-water 3 degress above body temp
-bathe 3 minutes
-pat dry
-apply emollients within 3 minture 3x daily
Emollients
-vaseline
-aquaphor
-cetaphil, cerave
-eucerin
-ointments vs creams vs lotions
Agents to reduce itching
-menthol + camphor
-praxomine
-aluminum acetate
-hydrocortisone
Menthol and camphor
-relieve itching
-0.5-1%
-cooling sensation
Praxomine
-relieve itching
-1%
-local anesthetic
Aluminum acetate
-relieve itching
-0.2%
-alters C-fiber nerve transmission
Hydrocortisone
-relieve itching
-0.5-1%
-anti-inflammatory
Dermatitis
-inflammatory process of upper two layers of skin
Acute dermatitis
-red patches/plagues
-pebbly surface or blisters
-INTENSE itching
-contact dermatitis
Contact dermatitis
-acute
-irritant vs allergic
-poison ivy
Sub-acute dermatitis
-dry
-less red
-crusting, oozing
-mild thickening
-itching common
-atopic dermatitis
Atopic dermatitis
-sub-acute
-eczema
Chronic dermatitis
-epidermal thickening
-exaggerated skin markings
-excoriations, fissures, scaling
-LICHENIFICATION
-less itching
-stasis dermatits
-any long standing acute/sub-acute dermatitis
Irritant contact dermatitis
-non-immunologic
-more common than allergic
-rx within a few hours
-metals, cosmetics, adhesives
Poison Ivy
-24-48 hrs after exposure
-Pruritis is intense (2’ infections)
-wash skin and nails within 10 min
-topical therapy okay if less than 10% of BSA
Poison Ivy tx
-remove source
-calamine
-topical antihistamines
-oral antihistamines
-topical vs oral corticosteroids
MOA of topical corticosteroids
-anti-inflammatory
-anti-mitotic
-immunosuppressive
-apply BID-QID 3-4 days
Oral corticosteroid regimen for acute dermatitis tx
-start Prednisone 40-60mg qd
-taper every 3 days
-minimum 10-14 days
-avoid dose packs bc they dont last long enough
Non-sedating antihistamines
-loratidine (claritin)
-Desloratidine (clarinex)
-Fexofenadine (Allegra)
Sedating antihistamines
-diphenhydramine (benadryl)
-cetirizine (zyrtec)
-Hydroxyzine (atarax) rx
-Doxepin rx
Atopic triad
-comorbidities:
1. atopic dermatitis
2. allergic rhinitis
3. asthma
atopic dermatitis
-pruritis
-sym red papules/plaques
-scaling
-DRY
-redness, inflammation
-hist of allergic disease
-risk of 2nd infection
Atopic dermatitis in infants
-cheeks
-neck, trunk, groin
Atopic dermatitis in children
-face, neck, creases of arms and legs
Atopic dermatitis in adult
-hands and neck
-arms and legs
Atopic dermatitis triggers
-detergents
-infections
Nonpharma tx of atopic dermatitis
-baths
-emollients
-avoid trggers
-trim nails
-comfy clothes
Stepwise tx of atopic dermatitis
- nonpharm
- topical
- systemic
- Acute flares
- Refractory
- Maintenance
Topical tx of atopic dermatitis
-corticosteroids
-calcineurin inhibitor therapy
-JAK inhibitor
-strength/duration based on severity
Systemic tx of atopic dermatitis
- phototherapy
- oral immunosuppresants
- oral JAK inhibitors
- injectable biologic agents
Acute flares tx of atopic dermatitis
-mod to severe
-medium-potency corticosteroid BID for up to 3 days beyond clearance of lesions
Refractory tx of atopic dermatitis
- phototherapy or oral immunosuppresives
- consider biologics
Maintenance therapy of mod to severe atopic dermatitis
-low topical corticosteroid qd
-OR TCS + anti-inflammatory 2-3x weekly
-written action plan
Chose TCS based on:
-location
-type
-severity
-degree of skin penetration desired
TCS potency
-very high - low (I-VII)
-vehicle impacts delivery AND potency
-only 2% absorbed into skin
Occlusion
-enhances penetration of TCS upto 10%
Side effects of TCS
-thinning of skin
-dilated blood vessels
-bruising
-skin coloring changes
-risk of HPA suppression w long-term use
-tolerance development (tachyphaylaxis)
Very high potency TCS Class 1
Betamethasone potency
-very high as ointment
-high as cream
-mod as lotion
slide48 maybe
Topical calcineurin inhibitors
-MOA: blocks pro-inflammatory cytokine genes
-can be used on any area
-equiv to mid potency TCS
-no risk of atrophy
-burning sensation
-$$$
-pimecrolimus and tacrolimues
Pimecrolimus and Tacrolimus
-topical calcineurin inhibitors
-2nd line tx of atopic dermatitis
-intermittent use only
-risk of malignancies
-risk infection in kids under 2
Crisaborole 2% ointment
-Phosphodiesterase-4 inhibitor (non steroidal)
-alt to TCS and TCI
-mild or mod AD
-BID for 28 days
-expensive
Ruxolitinib (Opzelura 1.5% cream)
-mild to mod atopic derm
-JAK inhibitor
-thin layer BID upto 20% BSA
-short term use
-max 60g/week
-AVOID in immunocompromised pts
Upadacitinib (Rinvoq)
-mod-severe atopic dermatitis
-JAK inhibitor
-15-30mg PO qd
-well tolerated
-higher rates of CV/thrombosis
Dipilumab (Dupixent)
-biologic for mod-severe atopic derm
-mAb against IL-4 a
-600mg then 300mg SC q 2 weeks
-expenziveee
