Master Vancomycin Toxicity & Side Effects

Vancomycin is a glycopeptide antibiotic used in the treatment of gram-positive bacterial infections. This antibiotic was originally indicated for the treatment of penicillin-resistant Staphylococcus aureus. Traditionally, it has been reserved as a drug of last resort, only after treatment with other antibiotics failed, and today, vancomycin-resistant organisms are increasing and becoming more common. This antibiotic inhibits cell wall mucopeptide synthesis by forming hydrogen bond interactions with the terminal D-alanyl-D-alanine moieties of the cell wall peptides. This binding to the D-Ala-D-Ala prevents synthesis of long polymers of N-acetylmuramic acid and N-acetylglucosamine, which normally forms the backbone strands of the bacterial cell wall and also prevents the polymers from forming cross-links. Resistance to vancomycin develops when the D-Ala-D-Ala moiety changes to D-ala-D-lac, preventing binding of vancomycin. Because gram-negative bacteria produce their cell walls via a different mechanism, vancomycin is not active against gram-negative bacteria. This antibiotic is indicated for the treatment of serious life-threatening infections caused by susceptible organisms including methicillin-resistant Staph aureus (MRSA), treatment of pseudomembranous colitis caused by the bacteria Clostridium difficile, and enterococci infections resistant to other penicillin derivatives. Well-known adverse reactions associated with IV vancomycin include thrombophlebitis, nephrotoxicity, ototoxicity and diffuse flushing known as vancomycin infusion reaction. Therefore, vancomycin must be administered slowly in a dilute solution. Vancomycin infusion reaction typically appears within 10 minutes after infusion and is characterized by flushing or an erythematous rash of the face, neck, and torso, due to nonspecific mast cell degranulation. Because of this mechanism of presentation, symptoms may be treated or prevented with antihistamines and are less likely to occur with a slow infusion rate.