Voriconazole

Generic Details

Generic Name

Voriconazole

Other Names

  • VFEND

Drug Class

  • Antifungal

Chemical Formula

C16H14F3N5O

Molecular Weight

349.31 g/mol

Mechanism of Action

  • Voriconazole inhibits the enzyme 14-alpha-sterol demethylase, resulting in the inhibition of ergosterol synthesis in fungi.

Indications

  • Invasive aspergillosis
  • Esophageal candidiasis
  • Serious fungal infections caused by Scedosporium apiospermum and Fusarium spp.

Common Dosage Forms

  • Tablet
  • Injection
  • Oral suspension

Typical Dosage

  • 200 mg every 12 hours on the first day, then 100-200 mg every 12 hours thereafter (oral)
  • 6 mg/kg every 12 hours on day 1, then 4 mg/kg every 12 hours thereafter (IV)

Pediatric Dosage

  • Dosage is weight-based and varies depending on the indication.

Geriatric Dosage

  • Adjust dosage based on renal function.

Side Effects

  • Visual disturbances
  • Liver function abnormalities
  • Skin reactions
  • Headache
  • Nausea
  • Vomiting

Contraindications

  • Hypersensitivity to voriconazole

Pregnancy Category

  • D

Lactation Safety

  • Limited data available; caution advised

Drug Interactions

  • Contraindicated with strong CYP3A4 inducers like rifampin
  • Interacts with warfarin, tacrolimus, and sirolimus among others

Overdose Symptoms

  • Hallucinations
  • Visual disturbances
  • Confusion

Antidote for Overdose

  • There is no specific antidote; manage symptoms and provide supportive care.

Storage Conditions

  • Store at room temperature below 30°C (86°F)

Pharmacokinetics

  • Absorption: Well absorbed orally
  • Distribution: Highly distributed in tissues
  • Metabolism: Metabolized in the liver
  • Excretion: Primarily excreted in the urine

Precautions

  • Monitor liver function tests periodically
  • Monitor renal function during therapy

Warnings

  • Risk of hepatotoxicity
  • Avoid direct sunlight exposure due to phototoxicity risk

Others

  • Before starting voriconazole therapy, patients should have baseline liver function tests and ECG.