potoski exam 1 stuff Flashcards
SOA Vancomycin?
Active: Gram (+) cocci, bacilli
Great for MRSA
inactive: gram negative
dosage form of vanco
IV for systemic, PO for C. difficile
how is vanco eliminated
renal elimination
therapeutic drug monitoring parameters for vanco
nephrotoxicity– AUC:MIC ratio is 400-600
serum trough concentrations 15-20 mcg/mL for serious infections
daptomycin dosage forms
IV only
not absorbed PO
daptomycin dosing
once daily dosing
dose adjustment in renal insufficiency
daptomycin cannot be used for _______, because ______
pneumonia, it is inactivated by lung surfactant
daptomycin spectrum of activity
Primarily active against aerobic Gram (+): S. aureus (including MRSA), strep. pyogenes, enterococcus faecalis and faecium (both vanco-sensitive and vanco-resistant strains)
INACTIVE AGAINST GRAM NEGATIVE, DRUG CANNOT PENETRATE THE GRAM NEGATIVE OUTER MEMBRANE
indications for daptomycin
therapy of complicated skin/skin structure infections produced by susceptible strains of gram (+) aerobes: MSSA, MRSA, strep, enterococcus faecalis
therapy of MRSA and MSSA bacteremia
other off label uses for MRSA
adverse reactions to daptomycin
rhabdomyolysis
injection site reactions, GI upset, CNS
FDA warning for daptomycin
eosinophilic pneumonia (therapy is cessation of drug and administration of steroids)
how to mitigate rhabdomyolysis with daptomycin
monitor CPK at baseline then weekly. D/c drug if CPK> 10x ULN or symptomatic with CPK> 5x ULN
what is the mechanism of daptomycin?
formation of a porin, allows for leakage of intracellular components, cell dies
linezolid dosage forms
IV and PO
PO bioavailability is 100%
linezolid is a ______
oxazolidinone
linezolid penetrates ___
CNS
linezolid activity
aerobic gram (+) bacteria: enterococcus faecium and faecalis, strep pneumoniae, viridans group strep, MRSA and MSSA, some anaerobic bacteria, mycobacteria
linezolid indications
skin and skin structure infections, VRE infections, nosocomial pneumonia, CAP
what are the side effects of linezolid?
thrombocytopenia, CNS, diarrhea, lactic acidosis, serotonin syndrome
when is thrombocytopenia from linezolid highest risk
after 14 days
why does serotonin syndrome happen from linezolid
MAO inhibitor
tedezolid doesn’t inhibit MAO, no serotonin syndrome
what is the mechanism of linezolid
binds to 23S portion of 50S ribosomal subunit and distorts binding site so it can’t bind to 30S subunit, prevents formation of 70S ribosome
telavancin dosage forms
IV only
not absorbed PO
what to monitor for telavancin
CrCL; dosage adjustments in renal impairment
telavancin spectrum of activity
MSSA and MRSA
vancomycin-susceptible enterococcus faecalis
strep
indications for telavancin
complicated skin and skin structure infections
HABP/VABP only when alternative treatments aren’t available
what is the BBW for telavancin
increased mortality with moderate/severe renal impairment
what is the mechanism of action of telavancin
it is a derivative of vancomycin + structural modifications
lipophilic side chain enhances cell wall disruptive activity
phosphonic acid improves distribution and antibacterial activity
ceftaroline dosage forms
IV only
ceftaroline clinical utility
MRSA
ceftaroline spectrum of activity
Good: strep, MSSA, MRSA, enteric GNRs
moderate: acinetobacter, enterococci faecalis
poor: enterococci faecium, pseudomonas, anaerobes
what is the indication for ceftaroline
use in combination with daptomycin in patients that fail to clear
what is the mechanism of ceftaroline
advanced generation cephalosporin with activity against MRSA because it binds to PBP 2a of MRSA that has a low affinity for other beta lactams
there is an additional risk of nephrotoxicity if vancomycin is used concomitantly with ______
piperacillin/tazobactam
vancomycin non-susceptible staphylococci include _________
vancomycin-intermediate staph. aureus (VISA)
vancomycin-resistant staph. aureus (VRSA)
what is the mechanism of VISA???
a thicker cell wall–> reduced cell wall cross linking
what is the mechanism of VRSA?
D-ala D-ala changes to D-ala D-Lac
common characteristics of VRSA
-co-infection/co-colonization with VRE (gets VanA gene from VRE via a transposon)
-prior use of vanco
-diabetes, ESRD, gangrenous wound, surgical wound
linezolid dosing
fixed, not weight based
600 mg IV or PO q12h
with linezolid, be careful with ____
SSRIs
telavancin is a ______
semisynthetic cyclic lipoglycopeptide