Aminoglycosides Flashcards
Aminoglycosides
Streptomycin Gentamycin Tobamycin amikacin Neomycin
Mechanism of action of aminglycosides
bind to 30s SU IRREVERSIBLY
- making it BACTERICIDAL
why can aminoglycosides work with B lactam
aminoglycosides (even though they are protease inhibitors) are BacteriCIDAL so they don’t interfere with the bactericidal effect of B lactam
Whats special about aminoglycosides
Dose Dependent*
greater efficacy with greater doses
and continue working even after they have dropped to MIC (post inhibitory effect)
spectrum of aminoglycosides
AEROBIC GRAM - BACTERIA
why don’t aminoglycosides work for anaerobes
aminoglycosides enter via oxygen transport mechanism that aerobes have
anaerobes lack this
what CANT aminoglycosides tx
STREP PYOGENES
STREP PNEUMO
What is the main mode of resistance to aminoglycosides
Enzymatic inactivation
Kinetics - aminoglycosides
Absorption
Oral absorption is ZERO
accumulate in renal cortex and inner ear
Adverse effects of aminoglycosides
OTOTOXICITY
- vestibular and auditory especially if taking ototoxic drugs (loop diuretics)
NEPHROTOXICITY
- irreversible tubular necrosis
neuromuscular paralysis
- block NMJ
Streptomycin
DOC
Yersinia pestis
Tularemia
2nd TB agent
Gentamycin and Tobramycin
tx
serious infections - bacteremia endocarditis meningitis pneumonia
MRsA
Gentamycin
DOC
Endocarditis due to Enterococcus infections
(pen G + Gentamycin)
(vancomycin + gentamycin)
gentamicin first line for
bacteremia due to viridans and agalactiae
meningitis- listeria ( ampicillin/ Pen G + gentamicin)
campylobacter fetus
brucellosis (+ doxycycline)
tobramycin
first line
pseudomonas
[zosyn, ceftazadime, cefipime, carbapenem, and aztreonam]
