Clinical Use of Antimicrobials in Equine Medicine Flashcards
what are the highest priority critically important antimicrobials?
cephalosporins 3rd and 4th generations
fluoroquinolones
what is MIC, MIC50, MIC90?
lowest antibiotic concentration that will inhibit 50%/90% of the visible microbial growth
what is Cmax?
peak drug concentration after its administration
what are the common gram positive aerobes in equine pneumonia?
Strep zoo and beta-hemolytic strep (>50%)
Staphylococci
Rhodococcus equi
what should you aim to do for time dependent antimicrobials?
keep drug levels above MIC for at least 80% of dosing interval
exert optimal bactericidal effect when drug concentrations are maintained above MIC
how does gentamicin work?
bind to 30s ribosomes: inhibit protein synthesis
disrupt cell wall precursors
what is Tmax?
time to reach peak drug concentrations
what determines total drug exposure?
area under the curve
what are the common gram negative aerobes in equine pneumonia?
Pasteurella
Actinobacillus
what should you do with time dependent antimicrobials?
keep drug levels above- ideally 2-4 times- MIC for at least 80% of dosing interval
what are the adverse effects of gentamicin?
potential ototoxicity
nephrotoxicity
what does it mean that a drug is concentration dependent?
higher the peak:MIC ratio, higher the kill rate
what is the best way to estimate MIC?
culture and sensitivity
which drugs are concentration dependent?
aminoglycosides
fluoroquinolones
