Pharmacology Flashcards
inhibits cell wall formation by interfering with incorporation of peptidoglycan subunits in bacterial cell wall
bacitracin
indicated for superficial gram+ skin or mucosal lesions
bacitracin
when would we consider mupirocin?
mupirocin can cover MRSA & some gram- skin infections
it is great for impetigo!
which medication is for GI tract or topical use only?
bacitracin
why do we not use bacitracin systemically?
it is highly nephrotoxic
what is the benefit of using either bacitracin and mupirocin?
no cross-resistance with other ABX
BUT: high-level of resistance to mupirocin can develop with prolonged use
which topical ABX is for skin or nasal use only, and is to be avoided over large areas & pressure ulcers?
mupirocin
what is the main side effect to warn your patients of when using bacitracin and mupirocin?
burning, stinging at application site
what is the MOA of mupirocin?
reversibly binds to tRNA synthase and inhibits bacterial protein synthesis
who do we avoid mupirocin in?
renal failure
which topical ABX do we use for superficial gram - infections?
polymixin B sulfate; good for pseudomonas, e. coli, enterobacter, klebsiella
do we use polymyxin B sulfate in treating gram+ infections?
NO; there is no gram+, proteus, and neisseria coverage secondary to resistance
although polymixin B sulfate is absorbed very minimally with topical use, what are signs of toxicity?
muscle weakness, paresthesias, vertigo, slurred speech
neurotoxic or ototoxic if absorbed
who to avoid polymyxin B sulfate in?
end stage renal disease; monitor CrCl
which of our drugs has an interaction with aminoglycosides?
polymixin B sulfate
what is the drug class & MOA of nystatin (mycostatin)?
oral/topical antifungal; binds to sterols in fungal cell membrane, increasing cell permeability
what is the indication for nystatin (mycostatin)?
topical skin & mucosal candida infections
what are side effects to warn your patient of when using 1) oral nystatin and 2) topical nystatin?
oral: N/D, bitter taste, SJS
topical: contact dermatitis
which anti fungal medication inhibits the uptake of precursors of macromolecular synthesis, inhibiting fungal cell membrane formation?
Loprox
what is the drug class of loprox?
azole antifungal; topical antifungal
when will we use loprox?
candida, tinea versicolor (malassezia furfur infections same thing as p orbiculare)
main side effect of loprox (shampoo)?
alopecia
which formulation of loprox do we want to use for oncychomycosis treatment? is it effective?
8% solution (penlac nail lacquer); not very effective–usually have to do systemic treatment
what formulation of loprox will we use for dermatomycosis, candidiasis, tinea versicolor infections?
creams/lotions
what class of drug is fluconazole (diflucan)?
oral antifungal (azole antifungal; fluorinated)
mechanism of action of fluconazole (diflucan)?
alters permeability of fungal cell wall
when will we use fluconazole?
candida & tinea species, fungal infections cryptococcal meningitis (AIDS)
your patient has been diagnosed with candida vaginitis, what is the best treatment option for her?
fluconazole; single 150 mg dose
who do we avoid using fluconazole in?
marked renal or hepatic disease (must adjust dose in renal disorders)
side effects of oral fluconazole?
seizures, N/V, dizziness, chemical hepatitis, SJS
which drug do we have to be super careful (and likely avoid) in patient’s with liver disease?
lamisil; monitor AST/ALT & hepatic function
drug drug interactions of lamisil?
tricyclic antidepressants increase toxicity of lamisil; lamisil decreases effectiveness of codeine
your patient’s kidney function is less than 50 percent CrCl and they want lamisil for their onychomycosis. what can you do?
you cannot prescribe it orally. you can attempt to use it topically
what is the main limitation of lamisil?
40% bioavailability (1st pass effect)
how much of lamisil is protein bound? why is this a good thing?
99% protein bound; accumulates in nails, skin & fat where we need it
this drug is a nucleoside anti-viral oral/topical medication
acyclovir
MOA of acyclovir?
blocks herpesvirus nucleic acid synthesis
signs of overdose with acyclovir?
tremors, seizures, delirium, nephritis
two main drug/drug interactions to be aware of with acyclovir?
1) probencid (gout) increases concentration & increases risk of renal & neuro toxicity
2) acyclovir decreases elimination of methotrexate so be careful with patients on this drug
what is the unique feature of acyclovir in regards to how our body processes the drug?
requires viral kinase activation, so accumulates ONLY in virus infected cells!
does resistance occur with acyclovir?
yes; should be effective up to 10 years
bioavailability of acyclovir is only ~10-30%. what happens when we increase the dose?
bioavailability actually DECREASES
your patient wants to take acyclovir prophylactically to prevent herpes outbreaks. what do you tell them?
it decreases the risk of viral shedding by ~90% & decreases risk of transmission by 50%
what is the name of the prodrug of acyclovir?
valcyclovir (valtrex); more potent but way more expensive
drug class of tretinoin?
acne topical; vitamin A or retinoic acid
MOA of tretinoin?
binds to retinoic acid & retinoic X receptor to regulate gene expression & increase epidermal cell turnover
when would we use tretinoin? what must you absolutely tell your patient about?
acne & photoaging (wrinkles). it causes a LOT of burning, stinging, dryness & the acne will get WORSE before it gets better
what should your patient avoid while using topical tretinoin?
astringents, abrasives (any scrubs with exfoliants), & not in pregnancy
which drug is our oral retinoic acid indicated ONLY for severe acne?
isotretinoin
what is the MOA of isotretinoin?
undefined to normal keratinization in sebaceous gland follicle & inhibits sebaceous gland size & function
it is VERY risky to prescribe isotretinoin. what are some side effects?
extreme dryness, anorexia, myalgias, lipid increase, bronchospasm, hepatotoxicity, premature epiphyseal closure, DEPRESSION & SUICIDAL THOUGHTS
(this medication has a lot of messed up side effects. we didn’t really stress that in class but i think its important to know in the real world)
drug class & MOA of benzoyl peroxide?
topical benzoid acid w/ undefined MOA but maybe antimicrobial activity against P acnes, peeling & comedolytic activity
what do you want to warn your patient of before prescribing benzoyl peroxide?
will make them really dry & photosensitive & will bleach their clothing!
which drug is our retinoid-like anti-acne agent?
adapaline (differin)
MOA of differin?
retinoid-like compound, a modulator of cellular differentiation, keratinization, and inflammatory processes
what should you warn your patient about when using differin?
photosensitivity, erythema & stinging (do not use on broken skin)
*vitamins ADEK will amplify photosensitization effect
your patient is interested in a topical with both retinoid & benozyl peroxide properties. what can we give?
epiduo; its a combo of adapaline & benzoyl peroxide
which drug is our topical pedicullicide, anti-parasitic agent?
permethrin 1% lotion/permethrin 5% cream
what is the MOA of permethrin?
inhibits Na channel in parasite cell membrane disrupting nerve transmission causing paralysis and death
when would we use the permethrin 5% cream?
scabies; will cause skin irritation
when would we use the permethrin 1% lotion rinse?
head lice; will cause skin irritation
can your patient get permethrin OTC?
NIX is OTC; otherwise Elemite is an RX (but contains formaldehyde!)
your patient has moderate psoriasis and is interested in treating it for the first time. what should you try first?
calcipotriene
drug class & MOA of calcipotriene?
psoriasis drug; topical vitamin D that regulates skin cell production/proliferation
side effects of calcipotriene?
burning, dry skin, skin atrophy, hyperpigmentation, hypercalcemia
what must you as a provider be aware of when prescribing calcipotriene?
less than 10 percent of people get total clearing with calcipotriene alone; likely have to add steroid
what do we need to monitor when giving a patient topical calcipotriene?
Ca+ response; also the drug may cause vitamin D toxicity & hypercalcemia
when should your patient using topical calcipotriene expect to see improvement?
2 weeks; 8 weeks max improvement
triamcinalone is availabile in two strength formulations. what are they?
1) 0.025% (intermediate efficacy; glucocorticoid & topical)
2) 0.5% (high efficacy topical & glucocorticoid)
besides topical, how else may you administer triamcinalone?
intralesional kenalog (when you inject someone with steroids)
MOA of triamcinalone?
attaches to GR receptor & inhibits protein synthesis
side effects of triamcinalone? why do you want to avoid long term use?
striae, increases susceptibility of infection, changes in fat distribution, cataracts
**LONG TERM USE will cause atrophy & thinning of the skin
who should we avoid long term triamcinalone in?
people on immunosuppressions or chronic NSAIDS
what is our HIGH strength topical steroid & glucocorticoid?
clobetasol
MOA of clobetasol?
same as triamcinalone! attaches to GR receptor & inhibits protein synthesis
side effects, DX/DX interactions, monitoring w/ clobetasol?
all same as triamcinalone!
SE: skin atrophy (worse bc higher potency)
DXDX: no NSAIDS, immunosuppressants
MONITOR: only if long term-lipids, glucose, CrCl
class & MOA of sulfasalazine?
oral psoriasis drug; MOA=undefined local impact; systemic impact of decreased prostaglandins & other inflammatory cytokine production
what are the indications for sulfasalazine?
off-label psoriasis & psoriatic arthritis, Crohns, ulcerative colitis
side effects of sulfasalazine?
N/V/D, photosensitivity, hemolytic anemia, SJS/TEN
who to avoid sulfasalazine in?
hepatic impairment; it is metabolized in the liver. monitor LFT & CrCl (renal clearance) if you have to give it
your patient just got the varicella vaccine. what do we need to be careful of given the fact that they are on sulfasalazine?
this vaccine increases the concentration of sulfasalazine
which drug is our folate antimetabolite drug indicated for psoriasis & RA?
methotrexate
MOA of methotrexate?
dihydrofolate reductase inhibitor which inhibits proliferation and induces apoptosis of immune-inflammatory cells
side effects of methotrexate?
PULMONARY & hepatic fibrosis, vasculitis & seizures
who to avoid methotrexate in?
alcoholic cirrhosis, renal or hepatic dysfunction
what to monitor when your patient is on methotrexate?
pulmonary function tests! also liver & kidney functino
class & MOA of hydroxyurea?
oral antimetabolite with undefined interference with DNA synthesis
when will we use hydroxyurea?
many! but psoriasis (off-label)
side effects of hydroxyurea?
alopecia, drowsiness, hepatotoxicity, peripheral neuropathy, PULMONARY FIBROSIS
like every oral psoriasis drug, what do we want to monitor?
CBC, LFT, CrCl (these people will be on these meds long term and you will definitely need to do this)
what do you need to make sure to do before prescribing your patient Enbrel?
PPD test; it is contraindicated in patient’s with TB
drug class of enbrel?
biologic response modifier (BRM); TNF alpha & beta blocker
MOA of enbrel?
blocks TNF alpha receptor binding thereby inhibiting TH1 activity
indications for enbrel?
refractory psoriasis unresponsive to other things, psoriatic arthritis, JRA, ankylosing spondylitis
side effects to be weary of with enbrel?
immunosuppression, anemia, exacerbation of CHF & demyelinating disorders
what other conditions must you pre-test before prescribing and avoid enbrel in if positive?
HIV, Hep B, CHF
how is enbrel given?
SQ injection every 1-2 weeks
drug class & MOA of polymyxin B sulfate?
topical ABX; interacts with phospholipids and disrupts bacterial cell membrane; binds to and activates endotoxin
