Linezolid, an
oxazolidinone antibiotic, has 100% oral bioavailability and favorable activities against gram-positive pathogens including multidrug-resistant staphylococci, enterococci, and pneumococci. Safety assessments were conducted for 2,046
linezolid-treated patients and 2,001 comparator
drug-treated patients from seven controlled clinical trials comparing the activities of
linezolid and comparator drugs against nosocomial and community-acquired
pneumonia, skin and skin structure
infections, and methicillin-resistant
staphylococcal infections.
Drug-related adverse events were primarily transient. The most frequent (> or = 2%) adverse events caused by
linezolid and the comparator drugs were
diarrhea (4.3 and 3.2%, respectively; P = 0.074),
nausea (3.4 and 2.3%, respectively; P = 0.036), and
headache (2.2 and 1.3%, respectively; P = 0.047). Treatment discontinuations due to
drug-related events (2.4 and 1.9%, respectively), serious adverse events (11.4 and 10.6%, respectively), and deaths (4.8 and 4.9%, respectively) were similar. No clinically significant
drug-related hematologic events were reported, and laboratory safety data were comparable. In the first 6 months of postmarketing surveillance, hematologic abnormalities were reported in 0.1% of
linezolid-treated patients, but no irreversible blood dyscrasias were documented. The risk for transient, reversible hematologic effects from treatment with
linezolid should be considered together with the clinical benefits associated with its use.