Pharmacology Flashcards
What are the main dermatology routes of drug administration
Topical
Transdermal
Subcutaneous
What is used to describe the structure of the stratum corneum
Brick and mortar model
What are the bricks in the model of the stratum corneum
Corneocytes containing keratin microfilaments in a fillagrin matrix
What is the mortar in the model of stratum corneum
Multiple lamellar structures of intercellular lipids
Role of intercellular lipids in the stratum corneum
Intracellular glue that can act as a reservoir for lipid-soluble drugs
How does a drug get through the stratum corneum when applied topically
Diffusion
What are the 3 main routes of diffusion of a drug through the stratum corneum
Transcellular route
Intercellular route
Transappendegeal route
Transcellular diffusion
Drug passes through both the lipid structures of the interlamellar region and moving across corneocytes
Intercellular diffusion
Drugs pass through small spaces between the cells of the skin
Transappendageal diffusion
Drugs are able to penetrate via hair follicles and sweat glands
Give 3 advantages of topically applied drugs
Allows for a steady plasma concentration over a prolonged period of time
Avoid first pass metabolism
Absorption can be terminated rapidly
Give 3 conditions that are managed with topical glucocorticoids
Atopic eczema
Psoriasis
Pruritus
Name the 4 major effects of topical glucocorticoids
Anti-inflammatory
Immunosuppressant
Vasoconstriction
Anti-proliferation action upon keratinocytes and fibroblasts
Trans activation mechanism of topical glucocorticoids
Bind to specific DNA responsive elements and upregulate the transcription of genes encoding for regulatory proteins responsible for metabolic, anti inflammatory, and immunosuppressive effects
Transgression mechanism of topical glucocorticoids
Repress gene expression by binding to negative DNA responsive elements or transcription factors that drive the expression of these gene
Describe subcutaneous drug administration
Needle inserted into the adipose layer just beneath the surface of the skin
What is electroporation
Creating new prose and temporary paths through the skin using electric pulses
What is iontophoresis
Involves applying low voltage electrical files to drive ionised drugs through the skin
What is a cream
Semi-solid emulsification of oil in water what contains preservatives and may cause contact sensitisation
Role of creams
Act to cool and moisturise the skin
What is an ointment
Semi-solid grease (oil) which have a high lipid content but no preservatives
Role of ointment
Occlusive and limit transdermal water loss
What is a lotion
Liquid formulation of medications suspended in alcohol or water
Role of lotions
Used to treat dry hair bearing areas
