Test Code

Quest Code

CPT Codes

Preferred Specimen
2 mL serum collected in a red-top tube (no gel)

Minimum Volume
1 mL

Other Acceptable Specimens
Plasma collected in: Sodium heparin (green-top) tube

Transport Temperature
Refrigerated (cold packs)

Specimen Stability
Room temperature: 5 days
Refrigerated: 5 days
Frozen: 30 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Serum separator tubes (SST®) • Other body fluids • Other specimen types

Chromatography/Mass Spectrometry

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by the U.S. Food and Drug Administration. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule

Report Available
1 to 2 Day(s)

Reference Range
Steady state trough levels are achieved within 1 day when an IV loading dose is used and after approximately 5 days of oral or IV therapy without a loading dose.

Therapeutic range
Prophylaxis: trough >0.5 mcg/mL
Therapeutic range for treatment: trough 2.0-5.5 mcg/mL

Serum trough levels less than or equal to 1 mcg/mL are reported to be associated with lack of therapeutic response and serum trough levels >5.5 mcg/mL have been reported to be associated with reversible neurological adverse events and hepatotoxicity.

Co-administration of drugs that metabolically induce or inhibit CYP2C19, or other conditions that affect CYP2C19 may alter voriconazole metabolism.

Clinical Significance
The antifungal drug voriconazole is commonly used in the treatment of various types of fungal infections. An increased fungal resistance to similar drugs of greater toxicity has promoted the use of voriconazole in treating infections caused by aspergillus and other fungal species. The chronic nature of fungal infections demands constant monitoring of voriconazole levels within a patient to ensure that adequate therapeutic levels of the drug are administered, absorbed and subsequently excreted.

Performing Laboratory
Quest Diagnostics Nichols Institute
27027 Tourney Road
Valencia, CA 91355-5386

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.