The antibacterial action of vancomycin

Vancomycin inhibits the second stage of cell wall synthesis in susceptible bacteria. Furthermore, there is evidence that vancomycin also alters the permeability of the cell membrane and selectively inhibits ribonucleic acid synthesis. Stable L-phase variants are susceptible to vancomycin, but induction of bacterial L-phase variants with vancomycin is very difficult. Vancomycin is active against a large number of species of gram-positive cocci and bacilli, such as Staphylococcus aureus (including methicillin-resistant strains), Staphylococcus epidermidis (including multiply resistant strains). Streptococcus pneumoniae (including multiply resistant strains), Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus bovis, viridans group Streptococcus, enterococcus, Clostridium species, diphtheroids, Listeria monocytogenes, Actinomyces species, and Lactobacillus species. Antimicrobial activity can be enhanced with the combination of vancomycin and an aminoglycoside against S. aureus, S. bovis, enterococcus, and viridans Streptococcus. The combination of vancomycin and rifampin also has enhanced activity against S. aureus.