4 CONTRAINDICATIONS
- VFEND is contraindicated in patients with known hypersensitivity to voriconazole or its excipients. There is no information regarding cross-sensitivity between VFEND (voriconazole) and other azole antifungal agents. Caution should be used when prescribing VFEND to patients with hypersensitivity to other azoles.
- Coadministration of pimozide, quinidine or ivabradine with VFEND is contraindicated because increased plasma concentrations of these drugs can lead to QT prolongation and rare occurrences of torsade de pointes [see Drug Interactions (7)].
- Coadministration of VFEND with sirolimus is contraindicated because VFEND significantly increases sirolimus concentrations [see Drug Interactions (7) and Clinical Pharmacology (12.3)].
- Coadministration of VFEND with rifampin, carbamazepine, long-acting barbiturates, and St John's Wort is contraindicated because these drugs are likely to decrease plasma voriconazole concentrations significantly [see Drug Interactions (7) and Clinical Pharmacology (12.3)].
- Coadministration of standard doses of voriconazole with efavirenz doses of 400 mg every 24 hours or higher is contraindicated, because efavirenz significantly decreases plasma voriconazole concentrations in healthy subjects at these doses. Voriconazole also significantly increases efavirenz plasma concentrations [see Drug Interactions (7) and Clinical Pharmacology (12.3)].
- Coadministration of VFEND with high-dose ritonavir (400 mg every 12 hours) is contraindicated because ritonavir (400 mg every 12 hours) significantly decreases plasma voriconazole concentrations. Coadministration of voriconazole and low-dose ritonavir (100 mg every 12 hours) should be avoided, unless an assessment of the benefit/risk to the patient justifies the use of voriconazole [see Drug Interactions (7) and Clinical Pharmacology (12.3)].
- Coadministration of VFEND with rifabutin is contraindicated since VFEND significantly increases rifabutin plasma concentrations and rifabutin also significantly decreases voriconazole plasma concentrations [see Drug Interactions (7) and Clinical Pharmacology (12.3)].
- Coadministration of VFEND with ergot alkaloids (ergotamine and dihydroergotamine) is contraindicated because VFEND may increase the plasma concentration of ergot alkaloids, which may lead to ergotism [see Drug Interactions (7)].
- Coadministration of VFEND with naloxegol is contraindicated because VFEND may increase plasma concentrations of naloxegol which may precipitate opioid withdrawal symptoms [see Drug Interactions (7)].
- Coadministration of VFEND with tolvaptan is contraindicated because VFEND may increase tolvaptan plasma concentrations and increase risk of adverse reactions [see Drug Interactions (7)].
- Coadministration of VFEND with venetoclax at initiation and during the ramp-up phase is contraindicated in patients with chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL) due to the potential for increased risk of tumor lysis syndrome [see Drug Interactions (7)].
- Coadministration of VFEND with lurasidone is contraindicated since it may result in significant increases in lurasidone exposure and the potential for serious adverse reactions [see Drug Interactions (7)].