From the Guidelines
Yes, cefdinir effectively covers gram-positive bacteria, as indicated by its inclusion as an alternative antimicrobial for Streptococcus pneumoniae in the Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults 1. This third-generation cephalosporin antibiotic is active against many important gram-positive pathogens including Streptococcus pneumoniae, Streptococcus pyogenes (Group A strep), and methicillin-susceptible Staphylococcus aureus (MSSA). Cefdinir works by binding to penicillin-binding proteins and inhibiting bacterial cell wall synthesis, ultimately causing bacterial cell death. The typical adult dosage is 300 mg twice daily or 600 mg once daily for 5-10 days, depending on the infection being treated. While cefdinir has good gram-positive coverage, it's essential to note that it does not cover methicillin-resistant Staphylococcus aureus (MRSA), enterococci, or certain other resistant gram-positive organisms. Cefdinir also provides coverage against many gram-negative bacteria, making it useful for mixed infections. Common side effects include diarrhea, nausea, and rash. It should be taken with food to enhance absorption, and patients should complete the full course of treatment even if symptoms improve before completion. According to the most recent guidelines from the WHO's Essential Medicines and Aware: Recommendations on First- and Second-Choice Antibiotics for Empiric Treatment of Clinical Infections 1, cefdinir is not listed as a first-choice antibiotic for skin and soft tissue infections, but its efficacy against gram-positive bacteria is well-established. In the context of skin and soft tissue infections, cefdinir may be considered as an alternative option, especially when first-line treatments are not suitable or effective, as suggested by the practice guidelines for the diagnosis and management of skin and soft-tissue infections 1 and 1.
From the FDA Drug Label
Cefdinir has been shown to be active against most strains of the following microorganisms, both in vitro and in clinical infections as described in INDICATIONS AND USAGE Gram-Positive Bacteria Staphylococcus aureus (methicillin-susceptible strains only) Streptococcus pneumoniae (penicillin-susceptible strains only) Streptococcus pyogenes
Cefdinir covers some gram-positive bacteria, including:
- Staphylococcus aureus (methicillin-susceptible strains only)
- Streptococcus pneumoniae (penicillin-susceptible strains only)
- Streptococcus pyogenes However, it is not effective against:
- Methicillin-resistant staphylococci
- Penicillin-resistant streptococci
- Enterococcus spp. 2 2
From the Research
Cefdinir Coverage of Gram-Positive Bacteria
- Cefdinir has a broad spectrum of activity against many gram-negative and gram-positive aerobic organisms, including Streptococcus pneumoniae, Staphylococcus aureus, and Streptococcus pyogenes 3, 4, 5, 6, 7
- The drug is effective against oxacillin-sensitive Staphylococcus aureus and coagulase-negative staphylococci, with an MIC90 of 0.015-2 mg/l 7
- Cefdinir also shows good activity against Streptococcus pneumoniae and Streptococcus pyogenes, with an MIC90 of 0.015-2 mg/l 7
- However, cefdinir is not active against methicillin-resistant, coagulase-positive or -negative staphylococci, with an MIC90 of > 64 mg/l 7
Specific Gram-Positive Bacteria Covered by Cefdinir
- Streptococcus pneumoniae: cefdinir has good activity against this bacterium, with an MIC90 of 0.015-2 mg/l 7
- Staphylococcus aureus: cefdinir is effective against oxacillin-sensitive S. aureus, but not against methicillin-resistant S. aureus 7
- Streptococcus pyogenes: cefdinir has good activity against this bacterium, with an MIC90 of 0.015-2 mg/l 7
- Enterococcus faecalis: cefdinir has greater activity against this bacterium than other cephalosporins, with an MIC90 of 16-32 mg/l 7