antibioticsbooks

58 PART 2 Antibacterial Drugs
Adverse Effects
Similar to those of other beta-lactams, with a possibly
higher incidence of AIN.
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Important Facts
• Antistaphylococcal penicillins have a short
half-life and must be dosed frequently. This
presents a problem, because they cause phlebitis.
Does your patient have phlebitis? Try a
first-generation cephalosporin instead.
• Most antistaphylococcal penicillins are eliminated
from the body in large part by the liver
and do not need to be adjusted in cases of renal
dysfunction.
• These drugs are interchangeable therapeutically.
Therefore, Staphylococcus aureus that is
susceptible to methicillin (which is no longer
used) is susceptible to oxacillin, nafcillin, and
the rest. That is, MSSA 5 OSSA 5 NSSA, etc.
What They’re Good For
Infections caused by MSSA, such as endocarditis
and skin and soft-tissue infections.
Don’t Forget!
Beta-lactams kill staphylococci more quickly than
vancomycin, so patients with MSSA infections
who lack serious beta-lactam allergies should be
switched to beta-lactams, such as antistaphylococcal
penicillins. This has been shown to be an important
difference in serious infections.