Antimicrobials
Voriconazole

Voriconazole

Low
Excellent
IV: $$$ PO: $$

Spectrum of Activity

General Information

Indicated as first line agent for invasive fungal infections by Aspergillus spp

Monitor weekly voriconazole serum trough concentrations every TUESDAY (levels are processed every Thursday morning at St. Paul's Hospital).

Target trough concentrations: 1 to 5.5 mg/L.

Steady-state concentrations require at least four days after onset of treatment or change in dose.

Invasive fungal infections by Aspergillus spp

  • Transient, dose-related visual disturbances occur in up to 45% of patients on voriconazole
    • This effect is most common in the first week of therapy and is reversible after patient becomes tolerant of voriconazole or after it is discontinued
  • Serious hepatic reactions and increase in liver function tests have been reported
  • Anaphylactoid type reaction may occur on initiation of IV infusion
  • Other ADR include:
    • Skin rash
    • Photosensitivity
    • Cardiac arrhythmias
    • Agranulocytosis
    • GI problems

Multiple, serious/life-threatening drug interactions involving the cytochrome P450 enzymes; check with pharmacy before initiating or stopping voriconazole therapy

  • Tablet: 50mg, 200mg
  • Injection: 200mg vials

Bioavailability 80%

Antimicrobial class: Triazole antifungal, second generation

Average serum half life: Variable and dose dependent

Route of Elimination: Urine (<2% as unchanged drug)