Antibacterial Agents IV Flashcards
What three fluoroquinolones do we need to know for class?
Levofloxacin, ciprofloxacin, and moxifloxacin
What combination of DNA precursor methylation is bactericidal?
Trimethoprim-sulfomethoxazole, because they inhibit sequential steps of the pathway
Lower UTIs are called cystitis and require __________; upper UTIs (pyelonephritis) require _________.
nitrofurantoin or trimethoprim-sulfamethoxazole; fluoroquinolones (or AGs, or ceftriaxone if resistance is suspected)
Antacids will decrease the bioavailability of ____________.
fluoroquinolones and penicillins
The big resistance mechanism for fluoroquinolones is _________.
changing the target (DNA gyrase)
Fluoroquinolones have ________ absorption and distribution.
good (very minimal protein binding)
The two fluoroquinolones that are impacted by renal dysfunction are ___________.
ciprofloxacin and levofloxacin, but not for moxifloxacin
The only fluoroquinolones that can kill anaerobic bacteria and atypical bacteria are _________.
moxifloxacin and gemifloxacin
Levofloxacin and moxifloxacin can kill __________.
Gram positive cocci
Levofloxacin is unique among the fluoroquinolones for its ability to kill _________.
Gram negative cocci
Only _________ can kill Gram positive rods (within the fluoroquinolone group).
ciprofloxacin
Levofloxacin and ciprofloxacin can kill _______.
Gram negative rods
Overall, fluoroquinolones are ________ tolerated.
well (slight increase in risk of tendon rupture)
Nitrofurantoin is toxic in those with _________.
renal insufficiency
Nitrofurantoins only kill ________.
Gram negative bacilli (not Neisseria)
Because they are so quickly excreted, nitrofurantoins have adverse side effects like ___________.
GI upset, anorexia, nephropathy with chronic use, vomiting, and diarrhea
Metronidazole treats __________.
protozoa and anaerobic bacteria
Metronidazole’s side effects include ___________.
nausea, headache, metallic taste, exacerbation of candidiasis infections (furry tongue), and Antabuse-like effect
Which drug inhibits dihydrofolate reductase?
Trimethoprim
Do not use sulfonamides in _________.
babies or pregnant women, because it raises the risk of kernicterus
What enzyme does sulfonamide target?
Dihydropteroate synthetase
The only two fluoroquinolones that can treat Pseudomonas aeruginosa are ________.
ciprofloxacin and levofloxacin
Which antibiotic colors the urine brown?
Nitrofurantoin
Where does metronidazole distribute to?
Everywhere, including CSF and bone
What is the trade name for TMP-SMX?
Bactrim (trimethoprim-sulfamethoxazole)
TMP-SMX kills ___________.
Gram-positive, Gram-negative, atypical, and anaerobic bacteria (including MRSA and Pseudo, except systemically)
List the two drug interactions and the one absorption factor relevant to fluoroquinolones.
Theophylline/caffeine; antacids
Can clindamycin kill Gram-negative bacteria?
No!
