Is fluconazole (Diflucan) a safe drug?

From the Guidelines

Diflucan (fluconazole) is generally considered a safe antifungal medication when used appropriately under medical supervision. According to the 2016 clinical practice guideline for the management of candidiasis by the Infectious Diseases Society of America 1, fluconazole has demonstrated efficacy comparable to that of AmB deoxycholate for the treatment of candidemia and is considered standard therapy for various fungal infections. The guideline recommends an average loading dose of 800 mg (12 mg/kg), followed by an average daily dose of 400 mg (6 mg/kg) for patients with invasive candidiasis.

Key Considerations

• Fluconazole is readily absorbed, with oral bioavailability resulting in concentrations equal to approximately 90% of those achieved by intravenous administration 1.
• It has the greatest penetration into the cerebrospinal fluid (CSF) and vitreous among the triazoles, achieving concentrations of >70% of those in serum 1.
• Fluconazole elimination is almost entirely renal, thus a dose reduction is needed in patients with creatinine clearance <50 mL/minute 1.
• Common side effects include headache, nausea, abdominal pain, and diarrhea, and it has significant drug interactions with medications like warfarin, certain statins, and some psychiatric medications.

Special Precautions

• Diflucan should be used cautiously in patients with liver disease 1.
• It is contraindicated during pregnancy, particularly in the first trimester, due to potential birth defect risks.
• Patients should be closely monitored for potential side effects and drug interactions when taking Diflucan, especially if they have underlying medical conditions or are taking other medications.

Dosage and Administration

• The typical adult dose ranges from 50-400mg daily depending on the infection type, with common treatment courses lasting 1-14 days for uncomplicated infections and potentially longer for severe cases 1.
• Always consult with a healthcare provider before taking Diflucan to ensure it's appropriate for your specific situation.

From the FDA Drug Label

Fluconazole is generally well tolerated. The overall incidence of side effects possibly related to fluconazole was 26%. The most common treatment-related adverse events reported in the patients who received 150 mg single dose fluconazole for vaginitis were headache (13%), nausea (7%), and abdominal pain (6%). Rarely, angioedema and anaphylactic reaction have been reported in marketing experience. In combined clinical trials and marketing experience, there have been rare cases of serious hepatic reactions during treatment with fluconazole.

Safety of Diflucan: Diflucan (fluconazole) is generally well tolerated, but it can cause side effects in some patients. The most common side effects are mild to moderate in severity and include headache, nausea, and abdominal pain. Rarely, serious hepatic reactions and anaphylactic reactions can occur.

• Common side effects:
  • Headache (13%)
  • Nausea (7%)
  • Abdominal pain (6%)
• Rare but serious side effects:
  • Angioedema
  • Anaphylactic reaction
  • Serious hepatic reactions 2

From the Research

Safety of Diflucan

• Diflucan (fluconazole) is generally well tolerated and infrequently associated with serious adverse effects or laboratory test abnormalities 3.
• Extensive clinical trials have demonstrated fluconazole's remarkable efficacy, favorable pharmacokinetics, and reassuring safety profile 4.
• The drug is water-soluble, rapidly absorbed after oral dosing, and penetrates well into body fluids and tissues, including cerebrospinal fluid, with an elimination half-life of approximately 30 h, allowing once-daily dosing 3.

Adverse Effects and Interactions

• Fluconazole is associated with a low risk of adverse effects, making it a safe treatment option for various fungal infections 3, 4.
• However, it is essential to consider potential interactions with other medications and underlying health conditions to minimize the risk of adverse effects.

Clinical Efficacy and Safety

• Clinical trials have shown that fluconazole is effective in treating various forms of candidiasis, including oropharyngeal, esophageal, and disseminated forms, as well as acute or suppressive therapy of cryptococcal meningitis 3, 4.
• The safety and efficacy of fluconazole have been evaluated in several studies, including those focusing on oropharyngeal candidiasis 5, 6, 7.