DIFLUCAN Dosage & Rx Info | Uses, Side Effects

Diflucan Generic Name & Formulations

Legal Class

General Description

Fluconazole 50mg, 100mg, 200mg; tabs.

Pharmacological Class

Azole antifungal.

How Supplied

Tabs—30; Susp (35mL)—1; IV—contact supplier

Manufacturer

Pfizer Inc.

Generic Availability

YES

Mechanism of Action

Fluconazole is a highly selective inhibitor of fungal CYP450 dependent enzyme lanosterol 14-α-demethylase. This enzyme functions to convert lanosterol to ergosterol. The subsequent loss of normal sterols correlates with the accumulation of 14-α-methyl sterols in fungi and may be responsible for the fungistatic activity of fluconazole.

Diflucan Indications

Indications

Oropharyngeal, esophageal candidiasis. Candidiasis prophylaxis in bone marrow transplant. Cryptococcal meningitis. Candida urinary tract infection (UTI), peritonitis, systemic infections.

Diflucan Dosage and Administration

Adult

All doses are once daily. Oropharyngeal candidiasis: 200mg on Day 1, then 100mg/day for at least 2 weeks. Esophageal candidiasis: 200mg on Day 1, then 100mg/day for at least 3 weeks; treat for at least 2 weeks after symptoms resolve; max 400mg/day. Systemic infections: doses of up to 400mg/day have been used. Prophylaxis in bone marrow transplant: 400mg/day; if anticipated severe granulocytopenia: see full labeling. Cryptococcal meningitis: 400mg on Day 1, then 200mg/day (400mg/day may be used) for 10–12 weeks after negative CSF cultures; to suppress relapse in AIDS: 200mg/day. UTI, peritonitis: 50–200mg/day have been used. Renal impairment (CrCl ≤50mL/min): see full labeling.

Children

All doses are once daily. Oropharyngeal candidiasis (≥6mos): 6mg/kg on Day 1, then 3mg/kg/day for at least 2 weeks. Esophageal candidiasis (≥6mos): 6mg/kg on Day 1, then 3mg/kg/day for at least 3 weeks; treat for at least 2 weeks after symptoms resolve; max 12mg/kg/day. Systemic infections (birth to 3mos postnatal age and gestational age <30wks): 25mg/kg on Day 1, then 9mg/kg/day; (birth to 3mos postnatal age and gestational age ≥30wks): 25mg/kg on Day 1, then 12mg/kg/day; (≥3mos): 25mg/kg (max 800mg) on Day 1, then 12mg/kg/day (max 400mg); for all: treat for at least 3 wks and for at least 2 wks after symptoms resolve. On ECMO (birth to 3mos postnatal age and gestational age <30wks): 35mg/kg on Day 1, then 9mg/kg/day; (birth to 3mos postnatal age and gestational age ≥30wks): 35mg/kg on Day 1, then 12mg/kg/day; (≥3mos): 35mg/kg (max 800mg) on Day 1, then 12mg/kg/day (max 400mg). Cryptococcal meningitis: 12mg/kg on Day 1, then 6mg/kg/day (12mg/kg/day may be used) for 10–12 weeks after negative CSF cultures; to suppress relapse in AIDS: 6mg/kg/day. Renal impairment (CrCl ≤50mL/min): see full labeling.

Diflucan Contraindications

Contraindications

Concomitant drugs known to prolong the QT interval and metabolized by CYP3A4 (eg, erythromycin, pimozide, quinidine).

Diflucan Boxed Warnings

Not Applicable

Diflucan Warnings/Precautions

Warnings/Precautions

Risk of serious hepatotoxicity; monitor liver function during therapy and for signs/symptoms of hepatic injury; discontinue if occurs. Proarrhythmic conditions. Monitor closely for skin rashes; discontinue if lesions progress. Allergy to other azoles. Renal or hepatic impairment. Susp: hereditary fructose, glucose/galactose malabsorption, sucrose-isomaltase deficiency: not recommended. Elderly. Use effective contraception during and for 1 week after last dose. Pregnancy: avoid; may cause rare congenital anomalies in infants exposed in-utero to high doses (400–800mg/day) during 1^st trimester. Nursing mothers.

Diflucan Pharmacokinetics

Absorption

Oral bioavailability: >90%. Peak plasma concentrations are reached between 1–2 hours.

Distribution

Apparent volume of distribution is approximately that of total body water. Plasma protein bound: 11–12%.

Metabolism

Hepatic.

Elimination

Renal (~91%). Half-life: ~30 hours (range: 20–50 hours).

Diflucan Interactions

Interactions

See Contraindications. Avoid concomitant voriconazole; if needed, monitor closely esp. when given within 24hrs after fluconazole. Caution with amiodarone (esp. with high-dose fluconazole), other drugs metabolized by CYP2C9, CYP2C19, and CYP3A4; monitor. Potentiates abrocitinib, lemborexant; avoid. Potentiates ivacaftor, fixed-dose ivacaftor combinations (eg, tezacaftor/ivacaftor, ivacaftor/tezacaftor/elexacaftor), warfarin, sulfonylureas, oral midazolam, theophylline, tofacitinib, tolvaptan, triazolam, alfentanil, amitriptyline, nortriptyline, saquinavir, sirolimus, carbamazepine, NSAIDs, zidovudine; monitor and adjust dose as necessary. May increase levels of phenytoin, halofantrine, ibrutinib, methadone, rifabutin, tacrolimus, vinca alkaloids, cyclosporine, fentanyl, CCBs, losartan, lurasidone; monitor. Concomitant celecoxib: reduce celecoxib dose by half. Increased risk of myopathy/rhabdomyolysis with concomitant HMG-CoA reductase inhibitors; may need dose reduction of these statins. Avoid concomitant lurasidone, olaparib; reduce its dose if unavoidable. May be potentiated by diuretics. May be antagonized by oral cimetidine, rifampin. Concomitant prednisone: monitor for adrenal cortex insufficiency when fluconazole stopped. Concomitant cyclophosphamide: increases serum bilirubin and creatinine; monitor. CNS effects with Vitamin A. Oral contraceptives: see full labeling. Avoid other hepatotoxic drugs.

Diflucan Adverse Reactions

Adverse Reactions

Nausea, headache, rash, vomiting, abdominal pain, diarrhea, dizziness; hepatotoxicity, adrenal insufficiency; rare: anaphylaxis, exfoliative dermatitis, QT prolongation, Torsade de pointes.

Diflucan Clinical Trials

See Literature

Diflucan Note