Transcript back_to_basics-pharmacology_2009

Pen V/G
Mostly G+, oral anarobes
Lacks efficacy vs BL G+,
G-, B. fragilis, atypicals
Penicillins
Develop agent Vs BL
staph (MSSA)
Develop agent vs Enterococcus and
“easy to kill” G- (non-BL’ase)
Ampicillin
Amoxicillin
Cloxacillin
Add G- and G+ BL
resistance and B. fragilis
Easy to kill G- bacteria: non-BL’ase H.
Flu, P. mirabilis, salmonella, shigella, E.
coli (L. monocytogenes is not a Gbacteria as was indicated here
previously)
Hard to kill G- bacteria: klebsiella,
enterobacter, citrobacter, serratia,
morganella, pseudomonas, providencia
Amoxicillin + Clavulanate
Ampi + sulbactam
Develop agent vs
“hard to kill” G-
Piperacillin, ticarcillin
Add BL resistance to
“easy to kill”
bacteria
Piperacillin/tazobactam
ticarcillin/clavulanate
Antibacterial agents-Penicillins
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β -lactams:
– Penicillins
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(1) Pen VK & Pen G: mostly for non β-lactamase producing G+ and oral anaerobes. Pen
V is PO while Pen G is by injection only. Commonly used for strep throat and mouth
infections. Agents of choice for syphilis even if patient is allergic to penicillins (need to
desensitize patient first!). Give Pen VK on empty stomach.
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(2) Methicillin & cloxacillin: for what (1) covers + BL’ase producing staphylococcus
(MSSA). Commonly prescribed for skin infections. Oral and parenteral. Give on empty
stomach. No dosage adjustment in renal dysfunction. Think of them as anti-staph.
(3) Ampicillin & amoxicillin: for what (1) covers + non BL’ase producing “easy to kill” Gbacteria & for ENTEROCOCCUS. Ampi is PO/IM/IV and causes diarrhea while Amoxi is
only PO.
(4) Amoxicillin+clavulanate & ampicillin+sulbactam: for what (3) covers + (2) + easy to
kill BL’ase producing G- bacteria + B. Fragilis + E. coli. Amoxi/clav frequently causes
diarrhea.
(5) Piperacillin & ticarcillin: for what (4) covers + Pseudomonas + non-BL’ase “hard to
kill” G- (often used in combo with aminoglycosides). Given parenterally only. Adjust
dose in renal impairement. Think of them as mainly anti-pseudomonal.
(6) Piperacillin+tazobactam & ticarcillin+clavulanate: for what (5) covers + MSSA
Pen G, ticarcillin, and piperacillin contain sodium which should be taken into account
when injecting them into patients with HF or renal insufficiency
Easy to kill G- bacteria: non-BL’ase H. Flu, P. mirabilis, salmonella, shigella (L. monocytogenes is
not a G- bacteria as was indicated here previously)
Hard to kill G- bacteria: klebsiella, enterobacter, citrobacter, serratia, morganella, pseudomonas