Skin Pharmacology Flashcards
Describe the ‘brick and mortar’ model of the stratum corneum
bricks= corneocytes containing keratin filaments mortar= lamellar structures of intercellular lipids
describe the difference between the intercellular and transcellular route
inter- travels through the intercellular lipids (most common)
intra- through corneocytes
name the various vehicles of topical drug administration (most lipid first)
lotions cremas ointments gels pastes powders
what is a prodrug
a medication that is administered in an inactive or less than fully active form, and is then converted to its active form through a normal metabolic process
describe what is meant by subcutaneous administration
drug delivered by a needle (inserted into the fatty tissue just beneauth the surface of the skin)
Name a drug administered subcut
insulin
what is transdermal drug delivery
drug is usually incorporated into a patch applied to epidermis
what drugs is TDD most suitable for
lipophilic
potent
brief half life
give examples of drugs delivered by TDD
nicotine, GTN, fentanyl, estradiol
give advantages of TDD
avoid first pass metabolism
rapid termination of action (if short half life)
What is iontophoresis
applies a few mA to a small area of skin via and electrode
what is electroporation
applies a short high voltage pulse
disrupts cell membrane
enhances skin permeability by four fold
Describe some of the properties of steroids when applied topically
anti-inflammatory
immunosuppressant
vasocontricting
anti-proliferatin action upon keratinocytes and fibroblasts
which form of hydrocortisone is more potent
butyrate more potent than acetate
how do steroids enter cells
lipophilic so enter by diffusion across the membrane
