Diflucan (fluconazole) is a systemic antifungal medication prescribed for the treatment and prevention of various fungal infections. As a member of the triazole class of antifungals, it works by inhibiting the synthesis of ergosterol, an essential component of fungal cell membranes, leading to fungal cell death. This medication is available in oral tablet, suspension, and intravenous formulations, providing flexibility in administration based on clinical need and patient factors. Healthcare providers prescribe Diflucan for its broad-spectrum activity against Candida species and Cryptococcus neoformans.

Features

• Active ingredient: Fluconazole 50mg, 100mg, 150mg, or 200mg tablets
• Available formulations: Oral tablets, oral suspension, and intravenous solution
• Mechanism: Inhibits fungal cytochrome P450-dependent enzyme lanosterol 14-α-demethylase
• Half-life: Approximately 30 hours (permits once-daily dosing)
• Bioavailability: Over 90% following oral administration
• FDA-approved since 1990 with extensive clinical documentation

Benefits

• Provides rapid symptomatic relief from fungal infections within 24-72 hours
• Offers convenient once-daily dosing regimen for improved adherence
• Demonstrates excellent tissue penetration, including central nervous system and urinary tract
• Shows broad-spectrum activity against most clinically significant Candida species
• Prevents recurrence of cryptococcal meningitis in immunocompromised patients
• Available in multiple formulations to accommodate different patient needs

Common use

Diflucan is primarily indicated for the treatment of oropharyngeal and esophageal candidiasis, vaginal candidiasis, systemic Candida infections including candidemia, disseminated candidiasis, and pneumonia. It is also used for cryptococcal meningitis treatment and maintenance therapy to prevent relapse in patients with AIDS. Additional uses include prophylaxis against fungal infections in patients undergoing bone marrow transplantation who receive cytotoxic chemotherapy and/or radiation therapy. Off-label uses may include treatment of other fungal infections such as coccidioidomycosis and blastomycosis when standard therapies are contraindicated or ineffective.

Dosage and direction

Dosage varies significantly based on indication, patient renal function, and clinical response. For oropharyngeal candidiasis: 200mg on first day followed by 100mg once daily for at least 2 weeks. For esophageal candidiasis: 200mg on first day followed by 100mg once daily for minimum 3 weeks. Vaginal candidiasis: single 150mg oral dose. For systemic Candida infections: 400mg on first day followed by 200mg once daily. Cryptococcal meningitis: 400mg on first day followed by 200-400mg once daily for 10-12 weeks after cerebrospinal fluid becomes culture-negative. Maintenance therapy for cryptococcal meningitis in AIDS patients: 200mg once daily. Dosage must be adjusted in patients with renal impairment (CrCl <50 mL/min). Tablets may be taken with or without food.

Precautions

Liver function tests should be monitored during prolonged therapy due to risk of hepatotoxicity. Use with caution in patients with renal impairment (dosage adjustment required). Electrolyte monitoring is recommended, particularly potassium and magnesium levels, as hypokalemia may occur. Caution is advised when prescribing to patients with underlying cardiac conditions or those taking medications that prolong QT interval. Patients should be advised that dizziness may occur and to use caution when driving or operating machinery. Pregnancy category D - should only be used during pregnancy if potential benefit justifies potential risk to fetus.

Contraindications

Hypersensitivity to fluconazole, other azole antifungal agents, or any component of the formulation. Coadministration with cisapride due to risk of serious cardiac arrhythmias. Concomitant use with erythromycin, terfenadine, astemizole, or pimozide. Patients with congenital or documented acquired QT prolongation. Severe hepatic impairment. Use in breastfeeding women requires careful risk-benefit assessment as fluconazole is excreted in human milk.

Possible side effect

Common side effects (≥1%) include headache (13%), nausea (7%), abdominal pain (6%), diarrhea (3%), dyspepsia (3%), dizziness (2%), and taste perversion (2%). Less frequent adverse reactions include rash (2%), vomiting (2%), and elevated liver enzymes (1-3%). Rare but serious side effects include hepatotoxicity (including rare fatalities), anaphylaxis, QT interval prolongation, torsades de pointes, seizures, leukopenia, thrombocytopenia, and severe dermatologic reactions including Stevens-Johnson syndrome. Alopecia has been reported in some patients receiving long-term therapy.

Drug interaction

Diflucan significantly inhibits CYP2C9, CYP2C19, and CYP3A4 enzymes, resulting in numerous clinically important interactions. It increases concentrations of warfarin (monitor INR closely), phenytoin, cyclosporine, rifabutin, theophylline, zidovudine, oral hypoglycemics, and statins. Coadministration with rifampin decreases fluconazole concentrations by approximately 25%. Hydrochlorothiazide increases fluconazole concentrations by approximately 40%. Significant interactions occur with numerous other medications including vinca alkaloids, benzodiazepines, calcium channel blockers, and certain antidepressants. Comprehensive medication review is essential before initiation.

Missed dose

If a dose is missed, it should be taken as soon as remembered unless it is almost time for the next scheduled dose. In that case, the missed dose should be skipped and the regular dosing schedule resumed. Patients should not double the dose to make up for a missed dose. For single-dose regimens (such as for vaginal candidiasis), if the dose is forgotten, it should be taken as soon as possible. If vomiting occurs within 1-2 hours of taking the medication, another dose may be needed (consult healthcare provider).

Overdose

Symptoms of overdose may include hallucinations, paranoid behavior, and exaggerated side effects. In cases of massive overdose, renal impairment and hepatotoxicity may occur. Treatment is supportive and symptomatic. Gastric lavage may be beneficial if performed soon after ingestion. Fluconazole is dialyzable (approximately 50% removed during 3-hour hemodialysis session), so hemodialysis may be considered in cases of significant overdose, particularly in patients with renal impairment. No specific antidote exists. Monitor cardiac function (ECG) and electrolyte levels in significant overdose.

Storage

Store at controlled room temperature 20-25°C (68-77°F). Keep container tightly closed and protect from moisture. Oral suspension should be stored between 5-30°C (41-86°F) and discarded after 2 weeks. Keep out of reach of children and pets. Do not use after expiration date printed on packaging. Do not transfer tablets or suspension to other containers. Protect from excessive heat and light. Do not freeze the oral suspension.

Disclaimer

This information is for educational purposes only and does not constitute medical advice. Diflucan is a prescription medication that should only be used under the supervision of a qualified healthcare professional. Individual response to medication may vary. Always follow your healthcare provider’s instructions regarding dosage, administration, and monitoring. Report any side effects to your healthcare provider promptly. This information is not exhaustive; consult the full prescribing information and discuss with your healthcare provider for complete information about risks and benefits.

Reviews

Clinical studies demonstrate Diflucan’s efficacy with cure rates of 80-90% for oropharyngeal candidiasis and 85-95% for vaginal candidiasis. In cryptococcal meningitis trials, success rates of 60-70% were observed with appropriate duration therapy. Many physicians appreciate its predictable pharmacokinetics and favorable drug interaction profile compared to older azoles. Patients frequently report satisfaction with the convenience of once-daily dosing and rapid symptom relief. However, some clinicians note emerging resistance patterns in certain Candida species, particularly C. glabrata and C. krusei, necessitating susceptibility testing in serious infections.