Fluconazole

Fluconazole is prescribed to treat:

• Vaginal yeast infections (candidiasis) • Oral and esophageal candidiasis (thrush) • Cryptococcal meningitis • Prevention of candidiasis in bone marrow transplant patients • Systemic candida infections • Urinary tract fungal infections • Peritonitis caused by Candida

It's effective against a wide range of fungal infections.

What is Fluconazole?

Fluconazole is a triazole antifungal medication widely used for treating and preventing various fungal infections. It's available as a single-dose treatment for vaginal yeast infections and for longer courses for more serious fungal infections.

How Does Fluconazole Work?

Fluconazole inhibits fungal enzyme cytochrome P450:

• Blocks ergosterol synthesis
• Disrupts fungal cell membrane formation
• Inhibits fungal growth and replication
• Fungistatic at lower doses
• Fungicidal at higher doses

Common Uses

• Vaginal Candidiasis: Single 150 mg dose
• Oral Thrush: 100-200 mg daily for 7-14 days
• Esophageal Candidiasis: 200 mg on day 1, then 100 mg daily for 2-3 weeks
• Cryptococcal Meningitis: Higher doses for extended periods
• Prophylaxis: In immunocompromised patients

Dosage and Administration

Vaginal Yeast Infection:

• Single 150 mg oral dose
• Can repeat in 3 days if needed
• Partner treatment usually not necessary

Oral Thrush:

• 200 mg on first day, then 100 mg daily
• Duration: 7-14 days
• Continue for at least 2 weeks

Systemic Infections:

• Higher doses (400-800 mg daily)
• Duration varies by infection and response

Administration Tips:

• Take with or without food
• Can be taken any time of day
• Oral suspension: shake well

Important Safety Information

Who Should Not Take Fluconazole?

• Hypersensitivity to fluconazole or other azoles
• Concurrent use with certain medications (see interactions)
• QT prolongation (use with caution)

Liver Toxicity Warning

⚠️ MONITOR LIVER FUNCTION:

• Rare but serious hepatotoxicity reported
• More common with longer treatment duration
• Monitor liver enzymes with prolonged use
• Stop if signs of liver damage

QT Prolongation

• Can prolong QT interval
• Risk of serious arrhythmias
• Use caution with:
  • Heart disease
  • Electrolyte imbalances
  • Other QT-prolonging medications

Drug Interactions

Strong CYP Enzyme Inhibitor - Many Interactions:

Contraindicated With:

• Terfenadine (with doses >400 mg/day)
• Astemizole
• Cisapride
• Pimozide
• Quinidine
• Erythromycin

Significant Interactions:

• Warfarin (increased INR - monitor closely)
• Phenytoin (increased levels)
• Cyclosporine (increased levels)
• Tacrolimus (increased levels)
• Statins (increased muscle toxicity risk)
• Benzodiazepines (increased sedation)
• Oral hypoglycemics (increased hypoglycemia risk)
• Rifampin (decreased fluconazole effectiveness)

Pregnancy

• Avoid in pregnancy (Category D)
• High-dose, long-term use associated with birth defects
• Single low-dose for vaginal infection: unclear risk
• Use only if benefit outweighs risk
• Reliable contraception recommended

Breastfeeding

• Excreted in breast milk
• Single dose likely compatible
• Consider alternatives for prolonged therapy

Recurrent Vaginal Yeast Infections

If 4 or more infections per year:

• May need longer initial treatment
• Consider maintenance therapy: 150 mg weekly for 6 months
• Investigate underlying causes (diabetes, antibiotics, immunosuppression)
• Rule out other conditions

Resistance

Antifungal resistance can develop:

• More common in immunocompromised patients
• HIV/AIDS patients with frequent use
• May need alternative antifungals
• Culture and sensitivity testing helpful

Special Populations

Elderly:

• Dose adjustment based on kidney function
• Monitor closely for side effects
• Higher risk of drug interactions

Kidney Disease:

• Dose reduction needed if CrCl <50 mL/min
• Loading dose same
• Reduce maintenance dose by 50%

Children:

• Safe for use in children
• Dose based on weight
• Commonly used for thrush in infants

Duration of Treatment

Varies by infection:

• Vaginal candidiasis: Single dose
• Oral thrush: 7-14 days
• Esophageal candidiasis: 2-3 weeks
• Cryptococcal meningitis: Months to years
• Prophylaxis: Duration of immunosuppression

When Treatment Fails

If symptoms persist:

• Confirm diagnosis (not all vaginitis is yeast)
• Rule out resistant strains
• Consider longer treatment
• Check blood glucose (diabetes)
• Evaluate for immunosuppression
• May need different antifungal

Monitoring

Monitor for:

• Liver function (with prolonged use)
• Kidney function
• Electrolytes (potassium, magnesium)
• Drug interactions
• Therapeutic response
• QT interval if at risk

Prevention of Yeast Infections

General measures:

• Avoid unnecessary antibiotics
• Control diabetes
• Wear cotton underwear
• Avoid douching
• Avoid irritating feminine products
• Probiotics may help (limited evidence)

When to Contact Your Doctor

• Symptoms not improving after 3 days
• Symptoms worsening
• Yellowing of skin or eyes
• Dark urine or pale stools
• Unusual fatigue or weakness
• Skin rash or blistering
• Irregular heartbeat
• Severe diarrhea
• Recurrent infections

Storage

• Store at room temperature
• Protect from moisture
• Keep oral suspension at room temperature
• Shake suspension well before use
• Do not freeze