Ch 26, 27 Treatment Flashcards
Principles of Topical Tx
- Horny layer is biggest barrier, diffusion a function of concentration and premeiability
- Nonpolar, small MW, with increased hydration and increased temperature absorbed more rapidly
Areas with rapid transformatino
-Face, folds, and scrotum are more easily absorbed
Factors effecting absorption
Molecular Weight Polarity Concentration Base Partition Coefficient Diffusion constant Horny layer thickness State of horny layer (Temp, hydration, integrity) Temperature
Steroid Actions
- Vasoconstrict
- Decrease phagocyte activation and migration
- Decrease Fibrin and Kinin Formation
- Inhibit PLA2
- Decrease Fibroblast activity
- Stabalize Lysosomal Membrane
- Decrease epidermal proliferaion
- Lympholytic and decrease cytokine expression
SE
Skin thinning, atrophy, stretch marks
- Telangectasia, bruising, hirsuitism, folliculitis, disguise infections
- Tachyphylaxis
- Rebound
Vehicles
Powders Alchohl based (tinctures) -Cream -Ointment -Gel Paste Spray Mousse -Lotions
Powders
-Flexures
Alchohol based
Hair
Lotions
- More watery
- drying skin, smoothing, cooling
Creams
-Cooling emolient and moisturizer
Ointments
Occlusive emolient
-Allows better absorption
Pastes
Protective emolient
Sprays
Drying and non-occlusive
Gels
Face/scalp
Mouse
Scalp
Preservatives
May cause allergy, especially parabens
Principles
-Use the least potent and monitor closely for side effects
Excision
- Used for biopsy
- Shave for exophytic likely benign tumors
- Saucerization for deeper tissues and to get subq fat
Curretage
- Destroys underlying tissue
- Healthy dermis is more resistant to curretage
Mohs indications
- Large basal cell carcinoma
- Scaring/cicatricial BCC
- BCC in sensitive area
- Recurrent BCC
- BCC with risk of recurrence (nose, glabella, nasolabial folds)
- Sometimes for SCC that is aggresive appearing
Cryotherapy
- Cellular components are more responsive to damage than stromal components
- Generally liquid nitrogen
Phototherapy
- UVB Narrowband: May be less carcinogenic, no need to protect skin peri-treatment from photosensitivity
- PUVA: Psoralen sensitizes, may be more effective and delivered in fewer sessions, penetrates deeper
PDT
- Apply sensitizer to skin that is absorbed over ~4 hours
- Leads to sensitivity of tissues to damage
- Blister and destruction of superficial skin (mostly oxygen radical induced)
IPL
-Noncoherent light on skin that causes absorption by a number of chromophores leading to photothermal damage relatively non-specifically
