antibioticsbooks

88 PART 2 Antibacterial Drugs
Moderate: enterococci (not ertapenem)
Poor: MRSA, penicillin-resistant streptococci
Adverse Effects
Similar to those of other beta-lactams, but imipenem
has a higher propensity to induce seizures.
Minimize the risk by calculating appropriate doses
for patients with renal dysfunction and avoiding
imipenem use in patients with meningitis, because
it can cross the blood–brain barrier more readily.
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Important Facts
• Imipenem is metabolized in the kidney to a
nephrotoxic product. Cilastatin blocks the renal
dehydropeptidase that catalyzes this reaction
and prevents this metabolism from occurring.
It is always co-administered with imipenem for
this reason.
• Carbapenems are very broad-spectrum agents.
Imipenem, doripenem, and meropenem are
particularly broad and should not be used
empirically for most community-acquired infections.
They are good choices for many types of
nosocomial infections, particularly in patients
who have received many other classes of antibiotics
during their hospital stay.
• Although ertapenem has weaker activity than
the other carbapenems for a few organisms,
this activity is significant enough to change the
utility of the drug (think: Ertapenem is the
Exception). Ertapenem is a poor choice for
many nosocomial infections, particularly nosocomial
pneumonia in which both Pseudomonas
and Acinetobacter are important pathogens.
However, it is administered only once a day