Voriconazole

C. diff Risk

Low

Oral Bioavailability

Excellent (90 to 100%)

Approximate Cost

$4.04 (PO)
$124.00 (IV)

Dosing

IV Administration
6mg/kg IV q12h x 2 doses then 4mg/kg IV q12h

PO Administration
400mg PO q12h x 2 doses then 200mg PO q12h

Dose reduction may be required if low body weight (i.e. less than 40 kg = 100 mg PO BID)

Standard loading dose then reduce maintenance by 50%
Mild to moderate (Child-Pugh A/B)

Should only be used if benefit outweighs risk
Severe impairment (Child-Pugh C)

General Information

Common Usage

Candida infections both mucocutaneous and invasive - i.e. Candidemia.

Antifungal prophylaxis in immunocompromised patients.

Drug Monitoring

Therapeutic drug monitoring may be helpful to ensure adequate concentrations and exclude toxicity (Discuss with ID).

Check with chemistry lab as specimen may need to be referred out of province.

QTc interval in patients at elevated risk.

Monitor hepatic profile.

Adverse Effects

  • Drug interactions

  • QTc prolongation

  • Hepatic enzyme abnormalities

  • Rash - up to 20%

  • Visual disturbance

  • Fluorosis

  • ¬†GI upset

Major Interactions

CYP450 interactions ++.

Other QTc prolonging agents.

Recommend review of pt medications due to high frequency of significant interactions.

Tablet/Capsule Strengths

PO: Requires special authorization

Additional Information

IV Administration
Dilute in 100 -250 mL D5W or NS and administer over 1-2 hrs.
Max concentration 5 mg/mL. Max rate 3 mg/kg/min

EH Prescribing Restrictions
None

Community IV Formulary (Metro)
NO

NLPDP Status
Requires Special Authorization

Note
Costs for PO are based on Eastern Health Contract Pricing. Costs are MARKEDLY higher in Community Setting

Pharmacology

Antimicrobial class: Triazole antifungal, Second generation

Pregnancy category: D

CSF penetration: Therapeutic

Lung penetration: Therapeutic

Urine penetration: Poor