Vancomycin is a tricyclic glycopeptide antibiotic derived from *Amycolatopsis orientalis*. It is a bactericidal agent primarily used for the treatment of severe infections caused by Gram-positive bacteria, particularly methicillin-resistant *Staphylococcus aureus* (MRSA) and *Clostridium difficile*. In the Indian context, it is a critical last-line antibiotic, with its use strictly controlled to combat antimicrobial resistance (AMR). The 1gm intravenous formulation is a standard high-dose vial for systemic infections.
Adult: 15-20 mg/kg/dose (based on actual body weight) every 8-12 hours. For most adults, a typical dose is 1gm (1000 mg) every 12 hours. For severe infections (meningitis, endocarditis, pneumonia), doses may be 15-20 mg/kg every 8-12 hours, not to exceed 2gm per dose.
Note: For IV use only. MUST be reconstituted with sterile water for injection (20 mL for 1gm vial to yield 50 mg/mL). Further dilute in at least 200 mL of compatible IV fluid (NS, D5W). Infuse over at least 60 minutes (for 1gm dose) to minimize 'Red Man Syndrome'. For higher doses or sensitive patients, infuse over 90-120 minutes. NEVER give as IV push or bolus.
Vancomycin inhibits the second stage of cell wall synthesis in susceptible bacteria. It binds with high affinity to the D-alanyl-D-alanine terminus of cell wall precursor units (lipid II).
Pregnancy: US FDA Category C. Crosses the placenta. Use only if clearly needed and potential benefit justifies potential risk to the fetus. Limited human data; animal studies show ototoxicity in fetus. TDM recommended.
Driving: Unlikely to affect driving ability. However, dizziness or vertigo from ototoxicity could impair performance; patients should be cautioned.
| Aminoglycosides (Gentamicin, Amikacin) | Additive/synergistic nephrotoxicity and ototoxicity. | Major |
| Loop Diuretics (Furosemide, Torsemide) | Increased risk of ototoxicity. | Moderate |
| Anesthetic Agents | Increased risk of erythema and histamine-like flushing. | Moderate |
| Cholestyramine, Colestipol | May bind oral vancomycin in GI tract, reducing its efficacy for *C. difficile* infection. | Moderate |
| Other Nephrotoxins (Amphotericin B, Cisplatin, IV Contrast) | Increased risk of acute kidney injury. | Major |