Does Linezolid (oxazolidinone antibiotic) cover Gram-positive cocci?

From the Guidelines

Linezolid is effective in covering gram-positive cocci, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE), with a recommended adult dosage of 600 mg orally or intravenously every 12 hours. The evidence from recent studies, such as the 2018 WSES/SIS-E consensus conference 1 and the 2014 practice guidelines by the Infectious Diseases Society of America 1, supports the use of linezolid as a valuable option for treating infections caused by resistant gram-positive organisms. Linezolid has excellent bioavailability when taken orally, making it suitable for both inpatient and outpatient treatment. However, it should be used with caution in patients taking serotonergic medications due to the risk of serotonin syndrome, and prolonged use (beyond 2-4 weeks) requires monitoring for potential adverse effects such as myelosuppression, particularly thrombocytopenia, and peripheral neuropathy.

Some key points to consider when using linezolid include:

• Its effectiveness in treating MRSA and VRE infections, as demonstrated by studies such as the Cochrane meta-analysis 1
• The importance of monitoring for adverse effects, particularly with prolonged use
• The suitability of linezolid for both inpatient and outpatient treatment due to its excellent oral bioavailability
• The need for caution when using linezolid in patients taking serotonergic medications due to the risk of serotonin syndrome

Overall, linezolid is a valuable option for treating gram-positive cocci infections, particularly those caused by resistant organisms, and its use should be considered in accordance with the latest clinical guidelines and evidence-based recommendations 1.

From the FDA Drug Label

Linezolid has been shown to be active against most isolates of the following microorganisms, both in vitro and in clinical infections... Aerobic and facultative Gram-positive microorganisms Enterococcus faecium (vancomycin-resistant strains only) Staphylococcus aureus (including methicillin-resistant strains) Streptococcus agalactiae Streptococcus pneumoniae (including multi-drug resistant isolates [MDRSP]1) Streptococcus pyogenes

Yes, Linezolid covers gram positive cocci, including Staphylococcus aureus and Streptococcus species, as listed in the drug label 2.

From the Research

Linezolid Coverage of Gram-Positive Cocci

• Linezolid has inhibitory activity against a broad range of gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and penicillin-resistant Streptococcus pneumoniae 3, 4, 5, 6, 7.
• The drug is effective against infections caused by MRSA, VRE, and other gram-positive cocci, including those with advanced antimicrobial drug resistance 3, 4, 5, 6, 7.
• Linezolid has been shown to be as effective as vancomycin in the treatment of patients with infections caused by methicillin-resistant staphylococci and VRE 3, 4.
• The MIC90 values for MRSA, VRE, PNSP, and GBS isolates were 4μg/ml, 2μg/ml, 1μg/ml, and 0.5μg/ml, respectively, indicating excellent activity against clinical drug-resistant Gram-positive isolates 6.

Spectrum of Activity

• Linezolid's spectrum of activity includes:
  • Methicillin-resistant Staphylococcus aureus (MRSA) 3, 4, 5, 6, 7
  • Vancomycin-resistant enterococci (VRE) 3, 4, 5, 6
  • Penicillin-resistant Streptococcus pneumoniae 3, 5, 6
  • Group B streptococci (GBS) 6
• Linezolid also shows activity against certain anaerobes, including Clostridium perfringens, C. difficile, Peptostreptococcus spp., and Bacteroides fragilis 3.