Fluoroquinolones Flashcards
What are 4 advantages to fluorinated quinolones?
1) broad spectrum of activity
2) excellent oral availability
3) tissue penetration
4) long half lives
What is the MOA for fluoroquinoloines?
inhibit bacterial topoisomerase II (DNA gyrase) and V – blocks DNA replication
___________ is the target for gram - bacteria while __________ is the target for gram +
topo II (gram-) topo V (gram+)
What are 4 MORs of fluoro?
1) altered target sites
2) expression of active efflux
3) altered cell wall permeability
4) cross resistance
What is the older FQ?
ciprofloxacin
What are the 2 newer ones?
levofloxacin
moxifloxacin
What benefit do the new FQs have over the old ones?
expanded gram + coverage
cipro only for gram -
What gram+ can newer FQs cover?
strep pneumo
What is the ONE FQ that does not cover pseudomonas?
moxi
cipro and levo have comparable coverage there
name the 4 atypical bacteria covered by FQs
1) legionella pneumophila (DOC)
2) chlamydophila
3) mycoplasma
4) ureaplasma
FQs are __________ dependent killing
conc
True or false: FQs have good bioavailbility after oral admin
TRUE
Where are the primary sites of distribution?
lung, bone
urinary tract and prostate: cipro/levo
CSF: moxi
How are FQs eliminated?
renally (cipro and levo)
hepatically (moxi)
What are FQs most commonly used for?
respiratory tract infections
What FQ cannot cover CA pneumo and why?
cipro (poor gram+ coverage)
but it CAN cover HA pneumo because that is pseudomonal
What do you use for HA pneumo?
cipro and levo
What drug do you use for exacerbations in cystic fibrosis?
cipro
What 2 FQs do you use for UTIs?
cipro and levo
Name 6 adverse effects of FQs
1) GI (nausea, vomiting)
2) CNS (headache)
3) hepatotoxicity
4) phototoxicity
5) cardiac (prolonged QT)
6) tendonitis
Can you give FQs to kids? or pregnant women?
No (articular cartilage damage)
What is a huge drug interaction shared by all PO FQs?
divalent and trivalent cations (impair absorption of orally administered FQs –> can lead to clinical failure)
(also all FQs interact with warfarin)
What does cipro interact with specifically
theophylline and cyclosporine
What is the gram NEG FQ?
cipro
Which FQ best serves pseudomonas?
cipro
What is the only FQ to serve anaerobes?
moxi
What is the only FQ that cannot serve UTIs?
moxi
What is metronidazole very useful against?
anaerobes
What is the MOA of metronidazole?
inhibits DNA synthesis (prodrug activated in body via ferredoxins)
What are 2 MORs for metronidazole?
1) altered growth requirements
2) altered ferredoxin levels
altogether uncommon resistance
What are the 2 main anaerobes treated with metronidazole?
bacterides
clostridium
True or false: metronidazole penetrates the CSF
true (PO and IV)
How is metronidazole eliminated?
liver and HD
What are 3 main uses for metronidazole?
1) anaerobic infections (intraab, pelvic, diabetic foot, decubitus ulcer, brain abscesses)
2) pseudomembraous colitis (C. diff)
3) trichomonas
What is the DOC for c. diff?
metronidazole
What are 3 adverse effects of metronidazole?
GI: stomatitis, metallic taste
CNS: peripheral neuropathy
