Voriconazole (Vfend ®)
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|NS, D5W, LR, LR/D5W, 0.45NS, D5W/NS|
Standard Dilutions [Amount of drug] [Infusion volume] [Infusion rate]
| [Prescribed dose ]
[Final concentration: 0.5 to 5 mg/ml]
[over 1-2 hours (a maximum rate of 3 mg/kg/hr)]
Reconstitute 200mg vial with 19ml of Water for Injection to obtain an extractable volume of 20 ml of clear concentrate containing 10 mg/ml of voriconazole. (Shake the vial until all the powder is dissolved.)
Stability / Miscellaneous
Vfend ® must be infused over 1-2 hours, at a concentration of 5 mg/mL or less. Therefore, the required volume of the 10 mg/m Vfend ® concentrate should be further diluted as follows:
1. Calculate the volume of 10 mg/ml Vfend® concentrate required based on the patient’s weight. (See package insert)
2. In order to allow the required volume of Vfend® concentrate to be added, withdraw and discard at least an equal volume of diluent from the infusion bag or bottle to be used. The volume of diluent remaining in the bag or bottle should be such that when the 10 mg/ml Vfend ® concentrate is added, the final concentration is not less than 0.5 mg/mL nor greater than 5 mg/mL.
3. Using a suitable size syringe and aseptic technique, withdraw the required volume of Vfend ® concentrate from the appropriate number of vials and add to the infusion bag or bottle. Discard Partially Used Vials. The final Vfend ® solution must be infused over 1-2 hours at a maximum rate of 3 mg/kg per hour.
DOSAGE AND ADMINISTRATION:
VFEND I.V. for Injection requires reconstitution to 10 mg/mL and subsequent dilution to 5 mg/mL or less prior to administration as an infusion, at a maximum rate of 3 mg/kg per hour over 1–2 hours (see Intravenous Administration).
NOT FOR IV BOLUS INJECTION
Blood products and concentrated electrolytes
Intravenous solutions containing (non-concentrated) electrolytes
Total parenteral nutrition (TPN)
Use in Adults
For the treatment of adults with invasive aspergillosis and infections due to Fusarium spp. and Scedosporium apiospermum, therapy must be initiated with the specified loading dose regimen of intravenous VFEND to achieve plasma concentrations on Day 1 that are close to steady state. On the basis of high oral bioavailability, switching between intravenous and oral administration is appropriate when clinically indicated (see package insert for CLINICAL PHARMACOLOGY). Once the patient can tolerate medication given by mouth, the oral tablet form or oral suspension form of VFEND may be utilized. (See Table below.)
Candidemia in nonneutropenic patients and other deep tissue Candida infections
Recommended Dosing Regimen
If patients are unable to tolerate 4 mg/kg IV, reduce the intravenous maintenance dose to 3 mg/kg every 12 hours.
Phenytoin may be coadministered with VFEND if the intravenous maintenance dose of VFEND is increased to 5 mg/kg every 12 hours, or the oral maintenance dose is increased from 200 mg to 400 mg every 12 hours (100 mg to 200 mg every 12 hours in adult patients weighing less than 40 kg) (see package insert: CLINICAL PHARMACOLOGY, PRECAUTIONS - Drug Interactions).
When voriconazole is coadministered with efavirenz, the voriconazole maintenance dose should be increased to 400 mg Q12h and the efavirenz dose should be decreased to 300 mg Q24h. When treatment with voriconazole is stopped, the initial dosage of efavirenz should be restored (see package insert: CLINICAL PHARMACOLOGY and PRECAUTIONS – Drug Interactions).
Duration of therapy should be based on the severity of the patient's underlying disease, recovery from immunosuppression, and clinical response.
Use in Geriatric Patients
Use in Patients with Hepatic Insufficiency
It is recommended that the standard loading dose regimens be used but that the maintenance dose be halved in patients with mild to moderate hepatic cirrhosis (Child-Pugh Class A and B).
VFEND has not been studied in patients with severe hepatic cirrhosis (Child-Pugh Class C) or in patients with chronic hepatitis B or chronic hepatitis C disease. VFEND has been associated with elevations in liver function tests and clinical signs of liver damage, such as jaundice, and should only be used in patients with severe hepatic insufficiency if the benefit outweighs the potential risk. Patients with hepatic insufficiency must be carefully monitored for drug toxicity.
Use in Patients with Renal Insufficiency
In patients with moderate or severe renal insufficiency (creatinine clearance <50 mL/min), accumulation of the intravenous vehicle, SBECD, occurs. Oral voriconazole should be administered to these patients, unless an assessment of the benefit/risk to the patient justifies the use of intravenous voriconazole. Serum creatinine levels should be closely monitored in these patients, and, if increases occur, consideration should be given to changing to oral voriconazole therapy (see DOSAGE and ADMINISTRATION).
Voriconazole is hemodialyzed with clearance of 121 mL/min. The intravenous vehicle, SBECD, is hemodialyzed with clearance of 55 mL/min. A 4-hour hemodialysis session does not remove a sufficient amount of voriconazole to warrant dose adjustment.
Source: [package insert]