antibioticsbooks

chapter 6 Beta-Lactams 67
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Important Facts
• Unlike the other members of this class,
amoxicillin/clavulanate is available orally.
Various doses are available, but higher doses
are associated with more diarrhea.
• The beta-lactamase inhibitors packaged in
these combinations are not active against all
beta-lactamases. New beta-lactamases with
the ability to destroy many types of betalactams
are continually being discovered and
are becoming more prevalent.
• Except for study purposes, beta-lactamase
inhibitors are not available outside of the combination
products.
• Sulbactam has useful activity against Acinetobacter
baumannii, a highly drug-resistant GNR
that causes nosocomial infections. For this reason,
high doses of ampicillin/sulbactam can be
used in the treatment of infections caused by this
organism.
• Amoxicillin/clavulanate and ampicillin/sulbactam
have nearly identical spectra of activity, but
clavulanate is more potent at inhibiting betalactamases
than sulbactam and higher doses
of sulbactam are given to account for this fact.
Differences in susceptibility testing may be due
to the low concentrations of sulbactam used
in tests.
What They’re Good For
Empiric therapy of nosocomial infections, particularly
nosocomial pneumonia (not aminopenicillin-based
combinations). Because they have
activity against aerobes and anaerobes, they are a