pharmacology and prescribing Flashcards
how are medications in the UK licensed?
MHRA - medicines and healthcare products regulatory agency
EMA - European medicines agency
name a process by which medicines are ensured to be of high standards of safety and quality?
SMC submission - Scottish Medicines Consortium
what is off-label medication?
licensed medication which is used for unlicensed indication
what are special medications?
unlicensed dermatological preparations
these tend to have a long history of use which is clinically effective, despite having no strong evidence base
name 4 reasons for prescription errors?
lack of knowledge - about patient, meds, allergies etc.
poor communication
mistake writing/ generating prescription
no local/ national guidelines
differentiate between pharmacokinetics and pharmacodynamics?
pharmacokinetics - effect of body on drug
pharmacoDynamics - effect of Drug on body
3 factors associated with pharmacokinetics?
distribution - where drug goes
metabolism - esp. liver disease
excretion - esp. renal disease
key factor affecting pharmacokinetics?
route of administration
optimal absorption is key - topical is often best
3 things to think about with pharmacodynamics?
age of patient
risk of pregnancy
drug interactions
4 factors associated with poor concordance to medication?
psychiatric co-morbidities
multiple applications per day
lack of patient education
unintentional non-adherence
2 components that combine to make a topical therapy?
vehicle + active drug
what is a vehicle?
pharmacologically inert, physically and chemically stable substance that carries the active drug
5 factors affecting absorption?
concentration of drug
base/vehicle used
thickness and hydration of stratum corneum
temperature
skin site
4 examples of vehicle?
solution
cream
gel
lotion
4 examples of topical drugs?
corticosteroid
anti-inflammatory
antibiotic
salicylic acid
topical steroids have anti-inflammatory and immunosuppressive properties - name 4 ways this is demonstrated?
regulation of pro inflammatory cytokines
vasoconstriction
suppress fibroblast, endothelial, leukocyte function
inhibition of vascular permeability
how much is a finger tip unit?
~0.5g
what size of area should a finger tip unit cover?
an area that is double the size of one hand
name 5 side effects of topical steroids?
thinning of skin striae bruising hirsutism glaucoma
which 3 classes of medication are used as systemic treatments?
retinoids
Immunosuppressants
biologics
what are retinoids and what are their function?
vitamin A analogues
normalise keratinocyte function
anti-inflammatory and anti-cancer effects
which retinoid, taken orally, is commonly used to treat acne?
Isotretinoin
which retinoid, taken orally, is commonly used to treat psoriasis?
Acitretin
which retinoid, taken orally, is commonly used to treat cutaneous T cell lymphoma?
Bexarotene