Vancomycin Unit Conversion

Vancomycin is a complex glycopeptide antibiotic, which has been used to treat penicillinase‑producing staphylococci. It is the drug of choice for the treatment of methicillin and related beta lactam antibiotic resistant Staphylococcus aureus as well as for the treatment of serious gram‑positive infections where allergies to penicillin or cephalosporin play a role. Vancomycin is also used in the treatment of antibiotic‑induced enterocolitis associated with Clostridium difficile and streptococcal or enterococcal endocarditis, the latter in conjunction with an aminoglycoside, when penicillin or ampicillin is not an option.

Monitoring of peak and trough serum or plasma levels is necessary due to potentially serious side effects including ototoxicity, nephrotoxicity, phlebitis, and reversible neutropenia.

Although optimum values may vary, peak serum values in the range of 25 to 40 μg/mL (17.3 to 27.6 μmol/L) and trough values in the range of 5 to 10 μg/mL (3.5 to 6.9 μmol/L) are generally accepted for therapeutic effectiveness.

Vancomycin is excreted primarily by the kidney in its unchanged active form although evidence of a nonrenal mechanism of elimination has been demonstrated. Impaired renal function can cause accumulation of the drug. Vancomycin has several adverse reactions, the most severe being ototoxicity and nephrotoxicity, although the purity of recent vancomycin preparations appears to have lessened these effects as long as serum concentrations are monitored closely. Nephrotoxicity is more likely to occur in patients receiving vancomycin in conjunction with an aminoglycoside.

The measurement of vancomycin concentrations in serum is essential to optimize therapy and avoid dosage related toxicity. This is especially important in patients with renal insufficiency, where individualized patient therapy is the only method to ensure optimal therapeutic serum levels without serious side effects.