EXAM 2 Misc antibiotics Flashcards
tertracycline MOA
reversibly bind to 30S subunit
Bacteriostatic, but may be bactericidal at high conc.
tetracycline MOR
Decreased accumulation of tetracycline in bacteria bc of altered permeability or efflux pumps
Decreased access of tetracycline to ribosome because of ribosomal protection proteins
Enzymatic inactivation
tetracycline drugs
tetracycline
doxycycline
minocycline
tetracycline anologs
tigecycline
omadacycline
eravacycline
tetracycline spectrum
MSSA and MRSA (mainly mino and doxy)
legionella
tetracycline analog spectrum
MSSA
MRSA
BDA (bacteroides)
tetracyclines and analogs absorption
Absorption can be impaired with consumption of di and trivalent cations
MAJOR DRUG INTERACTION
tetracyclines and analogs distribution
Widely distributed into body tissue and fluids, prostate
Minimal CSF penetration
tetracycline and demeclocycline elimination
renal elimination and require dose adjustments in renal insufficiency
Doxy and minocycline elimination
non renal metabolism
tetracycline analogs elimination
biliary elimination
dose adjust with liver disease (tige/erava)
tetracycline adverse effects
GI: N/V especially with tigecycline
Photosensitivity
Pregnancy category D –> discoloration of teeth and decrease bone growth
Which antibiotic will interact with cations cations so that oral absorption is impaired potentially leading to clinical failure?
Oral levofloxacin
Oral doxycycline
Oral ciprofloxacin
Oral minocycline
all of the above
all of the above
Which of the following does NOT have activity against atypical bacteria (legionella)?
Azithromycin
Levofloxacin
Amoixicillin-clavulanate
Doxycycline
Moxifloxacin
Amoxacillin-Clavulanate
Trimethoprim-Sulfamethoxazole MOA
TMP and SMX produce sequential block of folic acid synthesis
SMX: inhibits dihydropteroate synthetase
TMP: inhibits dihydrolate reductase
bactericidal
TMP-SMX spectrum
MSSA
MRSA
TMP-SMX elimination
Liver and kidney elimination
Dose adjustment when pts CrCl <30ml/min
TMP-SMX adverse effects
Leukopenia, thrombocytopenia
Hypersensitivity – RASH (sulfonamide portion)
Crystalluria, hyperkalemia, increased creatinine
TMP-SMX pregnancy
should not be used in term or lactating women
TMP-SMX drug interactions
warfarin
incerases anticoag effects
polymixin drugs
polymixin B
colistin
polymyxin MOA
Cationic detergents
Binds anionic lipopolysaccharides that cause displacement of Ca and Mg which change permeability and leak cell contents cell death
Concentration-dependent bactericidal activity
polymyxin MOR
alteration of outer cell membrane
cross-resistance is observed
polymyxin elimination
colistin and polymyxin B eliminated by nonrenal routes
polymyxin spectrum
pseudomonas
adverse effects polymyxins
nephrotoxicity
neurotoxicity
T/F Colistatin is often used to treat gram (-) aerobes because it is not associated with serious adverse effects
FALSE
only used for infections due to pseudomonas because of nephro and neurotoxicity
Clindamycin MOA
inhibits protein synthesis by exclusively binding 50S
Bacteriostatic, but may bactericidal when present at high concentrations
clindamycin MOR
Altered target sites
Active efflux
clindamycin spectrum
MSSA
MRSA (more active against CA-MRSA)
BDA
clindamycin distribution
tissue penetration including bone; minimal CSF penetration
clindamycin elimination
primarily metabolized by the liver
Not removed during hemodialysis
clindamycin adverse effects
C. Diff colitis
GI: N/V/D/Dys
which drugs cause C. diff colitis?
Clindamycin> ampicillin> penicillin, cephalosporin, carbapenems, FQs
metronidazole MOA
Inhibits DNA synthesis
selective toxicity against ferredoxins
prodrug
bacericidal
metronidazole MOR
altered growth requirements
altered ferredoxin levels
metronidazole spectrum
BDA
c. diff
metronidazole distribution
DOES penetrate CSF
metronidazole elimination
primarily metabolized by liver
metronidazole adverse effects
GI: stomatitis, metallic taste
CNS: peripheral neuropathy, seizures, encephalopathy
Mutagenicity, carcinogenicity
metronidazole drug interactions
Warfarin – anticoagulant effect
Alcohol – disulfiram reaction
Which antibiotic does NOT interact with warfarin?
TMP-SMX
Metronidazole
Ciprofloxacin
Clindamycin
Clarithromycin
Clindamycin
Which of the following is safe with pregnancy?
Ampicillin
Levofloxacin
Doxycycline
Metronidazole
Telavancin
Ampicillin
Which of the following does not require dosage adjustment in renal insufficiency?
TMP-SMX
Vancomycin
Gentamycin
Cefazolin
Nafcillin
Nafcillin
Which of the following is NOT associated with nephrotoxicity?
Metronidazole
Vancomycin
Tobramycin
Colistin
Nafcillin
Metronidazole
