EXAM 2 fluoroquinolones and macrolides Flashcards
Fluoroquinolones drugs
ciprofloxacin
levofloxacin
moxifloxacin
delafloxacin
fluoroquinolones MOA
rapid bactericidal
Inhibit DNA synthesis by inhibiting topoisomerase needed for DNA synthesis
topo 2 (DNA gyrase) removes supercoiling
topo 4: essential for separation of interlinked daughter DNA molecules
fluoroquinolones MOR
altered binding sites
expression of active efflux
altered cell wall permeability
cross-resistance between FQs
levo, moxi, dela spectrum
PRSP
MSSA
MRSA (dela)
Pseudomonas (levo and dela)
legionella
Cipro spectrum
MSSA
pseudomonas
fluoroquinolones pharmacology
AUC/MIC correlates efficacy
rapid bactericidal
fluoroquinolones Distribution
Extensive tissue penetration –> lung, bone, prostate
minimal CSF penetration
fluoroquinolones elimination
Renal: cipro, levo, dela
hepatic: moxi
none removed during dialysis
fluoroquinolones adverse effects
neurologic - peripheral neuropathy
cardiac - prolong QTC –> TdP
articular cartilage damage - CI in pregnant
tendonitis/tendon rupture
fluoroquinolones drug interactions
divalent and trivalent cations - all PO FQs
warfarin - all FQs
theophylline and cyclosporine - cipro
macrolide drugs
erthyromycin
clarithromycin
azithromycin
macrolide MOA
inhibit protein synthesis by reversble binding to the 50S ribosomal subunit
bacteriostatic, but can be bactericidal in high conc
macrolides MOR
active efflux: Mef gene
altered binding sites: Erm gene
cross-resistance occurs between all macrolides
Macrolides spectrum
MSSA
legionella (DOC)
macrolides spectrum gram (+)
Clarithromycin > Erythromycin > Azithromycin
macrolides spectrum gram (-)
Azithromycin> Clarithromycin > erythromycin
macrolides absorption
erythromycin: destroyed by gastric acid
clarithromycin: acid stable
azithromycin: acid stable
macrolides distribution
large VD
minimal CSF penetration
erythromycin elimination
excreted in bile and metabolized by CYP450
clarithromycin elimination
primarily eliminated by kidneys
requires dose adjustments at CrCl < 30
azithromycin elimination
biliary excretion
macrolides adverse effects
GI - NVD take with food if possible
Thrombophlebitis - dilute dose, slow admin, large vein
QTc prolongation
macrolides drug interactions
eythromycin and clarithromycin inhibit cytochrome P450 increase conc:
throphylline
carbamazepine
cylcosporine
phenytoin
warfarin
digoxin
valproic acid
which of the following antibiotics does not have activity against atypical (legionella)?
Azithromycin
Levofloxacin
Amoxicillin-clavulanate
Clarithromycin
Moxifloxacin
Amoxicillin-clavulanate
Which of the following antibiotics is least likely to interact with warfarin?
Azithromycin
Levofloxacin
Ciprofloxacin
Clarithromycin
Moxifloxacin
Azithromycin
