13. Aminoglycosides

Question 1

Aminoglycosides

Answer 1

Neomycin
Paromycin
Streptomycin
Gentamicin
Tobramycin
Amikacin
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-binding to the 30s ribosomal subunit

-activity against aerobic gram negatives, actively transported cell membrane

-coupled with cell wall active drugs
(beta-lactams, vancomycin) to allow entry into the cell

-transported into bacteria via an oxygen dependent process (aerobic bacteria)

• ivy administration

-Neomycin remains active in the GI tract until secreted with feces

• neomycin used in bowel prep before colorectal surgery
• Paromycin, luminal agent active against parasital infections
• ——————————————————————————–streptomycin treats tularemia caused by Francisella tularensis
• streptomycin treats the plague caused by Yersinia pestis
• gentamycin treats resistant gram negative infections (Enterobacter, serratia, Klebsiella)

-systemic gram negative infections
(septicemia, nosocomial RTI, complicated UTI, intra-abdominal infection)

• activity against pseudomonas (aerobic gram negative)
• tobramycin -activity similar to gentamycin
• activity against enterococcus when coupled with a cell wall active agent (penicillin, vancomycin)

-inactivated by an acetylation enzyme
(E. faecium against tobramycin)

• Amikacin Activity against E. faecium w/ acetylation enzymes

-Activity against pseudomonas
(gentamycin, tobramycin, amikacin)
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-myasthenia gravis is an absolute contraindication to aminoglycoside use, due to post NMJ Blockade
-Teratogenic – deafness in newborn
ototoxicity (vestibular or cochlear damage)

• nephrotoxicity (due to acute tubular necrosis)
• acute tubular necrosis (brown casts)

Peaks and troughs in undulating terrain: monitoring of serum drug levels