Vanazole Special Precautions

Visual changes, including blurred vision, changes in visual acuity, color perception, and photophobia, are commonly associated with treatment; postmarketing cases of optic neuritis and papilledema (lasting > 1 month) have also been reported. Patients should be warned to avoid tasks which depend on vision, including operating machinery or driving. Changes are reversible on discontinuation following brief exposure/treatment regimens (≤ 28 days).
Serious hepatic reactions (including hepatitis, cholestasis, and fulminant hepatic failure) have occurred during treatment, primarily in patients with serious concomitant medical conditions. However, hepatotoxicity has occurred in patients with no identifiable risk factors. Use caution in patients with pre-existing hepatic impairment (dose adjustment or discontinuation may be required). Voriconazole tablets contain lactose; avoid administration in hereditary galactose intolerance, Lapp lactase deficiency, or glucose-galactose malabsorption. Acute renal failure has been observed in severely ill patients; use with caution in patients receiving concomitant nephrotoxic medications.
Use caution in patients taking strong cytochrome P450 inducers, CYP2C9 inhibitors, and major 3A4 substrates; consider alternative agents that avoid or lessen the potential for CYP-mediated interactions. QT interval prolongation has been associated with voriconazole use; rare cases of arrhythmia (including torsade de pointes), cardiac arrest, and sudden death have been reported, usually in seriously ill patients with comorbidities and/or risk factors (eg, prior cardiotoxic chemotherapy, cardiomyopathy, electrolyte imbalance, or concomitant QT_c- prolonging drugs). Use with caution in these patient populations; correct electrolyte abnormalities (eg, hypokalemia, hypomagnesemia, hypocalcemia) prior to initiating therapy.
Rare cases of malignancy (melanoma, squamous cell carcinoma) have been reported in patients (mostly immunocompromised) with prior onset of severe photosensitivity reactions and exposure to long-term voriconazole therapy. Other serious exfoliative cutaneous reactions, including Stevens-Johnson syndrome, have also been reported. Patient should avoid strong, direct exposure to sunlight; may cause photosensitivity, especially with long-term use. Discontinue use in patients who develop an exfoliative cutaneous reaction or a skin lesion consistent with squamous cell carcinoma or melanoma. Periodic total body skin examinations should be performed, particularly with prolonged use.
Monitor pancreatic function in patients (children and adults) at risk for acute pancreatitis (eg, recent chemotherapy or hematopoietic stem cell transplantation); there have been postmarketing reports of pancreatitis in children.