Tag Archives: therapeutic drug monitoring

The Evidence behind Continuous-Infusion Vancomycin Therapy

Vancomycin is typically given as an intermittent infusion adjusted for body weight and renal function.  Some clinicians believe that a continuous infusion of vancomycin may simplify therapy and make serum vancomycin levels more consistent.

Goal Vancomycin Level (Plateau)

Because continuous infusion vancomycin is a rare clinical occurrence, there is a lack of data regarding the optimal “plateau” level (serum drug level during continuous infusion therapy).  Current evidence suggests that the vancomycin AUC:MIC ratio is the most important pharmacodynamic parameter associated with treatment success.1  Given that current guidelines recommend an AUC:MIC ratio of at least 400, a plateau of 20-25 mcg/mL (20 mcg/mL * 24 hrs) would provide an AUC:MIC ratio > 400 for isolates with an MIC of 1-1.5 mcg/mL. Continue reading

How to Interpret a Voriconazole Drug Level

Voriconazole (VFEND®) is a second-generation azole antifungal that inhibits 14-α-demethylase, causing reduced production of ergosterol, a critical component of the fungal the cell wall.  Voriconazole has a broader spectrum of activity than fluconazole and is often used for the treatment of invasive aspergillosis.  Voriconazole serum concentrations are difficult to predict because of its saturable metabolism, non-linear pharmacokinetics, and poor correlation to weight-based dosing.1 Continue reading