Pharmacology of Vancomycin


Vancomycin, a glycopeptide antibiotic, is a critical agent in the treatment of severe Gram-positive bacterial infections, especially those caused by methicillin-resistant Staphylococcus aureus (MRSA) and enterococci. It is often reserved for cases where other antibiotics are ineffective.

Chemical Structure and Properties


Vancomycin is a complex tricyclic glycosylated peptide with a molecular formula of C66H75Cl2N9O24. It is poorly absorbed from the gastrointestinal tract and is therefore commonly administered intravenously for systemic infections.

Mechanism of Action

Vancomycin exerts its antibacterial effect by inhibiting cell wall synthesis in bacteria. It binds with high affinity to the D-alanyl-D-alanine terminus of cell wall precursors, thereby preventing the incorporation of these precursors into the cell wall matrix. This action leads to cell wall weakening and ultimately bacterial cell death.


  • Absorption: When given orally, Vancomycin is poorly absorbed and is primarily used for treating colonic infections like Clostridioides difficile colitis. Intravenous administration is used for systemic infections.
  • Distribution: It distributes widely in body tissues, including bones and pleural, pericardial, ascitic, and synovial fluids. However, penetration into the central nervous system (CNS) is limited unless the meninges are inflamed.
  • Metabolism: Vancomycin undergoes minimal metabolism.
  • Excretion: Primarily excreted by the kidneys. Dose adjustment is necessary in patients with renal impairment to prevent toxicity.

Clinical Uses

  • Serious Gram-Positive Infections: Used in severe infections caused by MRSA, streptococci, and enterococci.
  • Endocarditis and Meningitis: Effective in treating endocarditis and bacterial meningitis caused by susceptible organisms.
  • Bone and Joint Infections: Used in complex bone and joint infections, including osteomyelitis and septic arthritis.
  • Clostridioides difficile Colitis: Oral vancomycin is a treatment of choice for severe C. difficile colitis.

Adverse Effects

  • Nephrotoxicity: Renal impairment can occur, particularly with higher doses or prolonged therapy.
  • Ototoxicity: Rare but potentially serious, especially when used in combination with other ototoxic drugs.
  • Infusion-Related Reactions: Rapid infusion can cause “Red Man Syndrome,” characterized by flushing, rash, and hypotension.
  • Phlebitis: Local irritation and phlebitis can occur at the injection site.
  • Hematological Effects: Neutropenia and thrombocytopenia have been reported with prolonged use.

Contraindications and Precautions

  • Allergy: Contraindicated in patients with known hypersensitivity to vancomycin.
  • Renal Impairment: Requires dosage adjustment and careful monitoring.
  • Pregnancy and Breastfeeding: Should be used during pregnancy only if clearly needed and with caution during breastfeeding.

Drug Interactions

  • Nephrotoxic Agents: Concomitant use with other nephrotoxic drugs (like aminoglycosides) increases the risk of renal toxicity.
  • Anesthesia: Intravenous vancomycin can potentiate the neuromuscular blockade produced by anesthetic agents.
  • Ototoxic Drugs: Increased risk of ototoxicity when used with other ototoxic agents.

Special Considerations

  • Monitoring: Therapeutic drug monitoring is often recommended to ensure efficacy while minimizing toxicity, especially in patients with renal impairment.
  • Administration: Slow intravenous infusion over at least one hour is recommended to reduce the risk of infusion-related reactions.


Vancomycin remains a vital antibiotic for treating serious infections caused by resistant Gram-positive bacteria. Its clinical use necessitates careful dose managemen

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always seek the advice of a healthcare provider with any questions regarding a medical condition.

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