What is the first‑line therapy for uncomplicated vulvovaginal candidiasis in an otherwise healthy adult woman?

First-Line Treatment for Vaginal Yeast Infection

For uncomplicated vulvovaginal candidiasis in an otherwise healthy adult woman, prescribe a single oral dose of fluconazole 150 mg—this achieves >90% clinical cure rates and is the preferred first-line therapy. 1, 2, 3

Diagnostic Confirmation Before Treatment

Before prescribing fluconazole, confirm the diagnosis to avoid treating the wrong condition:

• Perform wet mount microscopy using 10% potassium hydroxide to visualize yeast or pseudohyphae 1, 2
• Measure vaginal pH, which should be ≤4.5 for candidiasis (pH >4.5 suggests bacterial vaginosis or trichomoniasis) 1, 2
• Obtain vaginal culture if wet mount is negative but symptoms persist 1, 2

Symptoms of pruritus, discharge, dysuria, and dyspareunia are nonspecific and can result from multiple infectious and noninfectious causes, making laboratory confirmation critical before treatment 1.

First-Line Regimen: Oral Fluconazole

Fluconazole 150 mg as a single oral dose is the standard first-line therapy endorsed by the Infectious Diseases Society of America and FDA labeling 1, 2, 3:

• Clinical cure rates: 80-90% at short-term evaluation (5-16 days post-treatment) 1, 4
• Mycologic eradication rates: 60-77% 1
• Symptom relief occurs more rapidly than with topical agents 5
• Long-term efficacy: 91% clinical cure at 80-100 days post-treatment 4

Alternative First-Line: Topical Azoles

If the patient prefers topical therapy or has contraindications to oral fluconazole, short-course intravaginal azoles achieve comparable efficacy 1:

• Clotrimazole 500 mg intravaginal tablet as a single application 1
• Miconazole 200 mg suppository once daily for 3 days 1
• Terconazole 0.8% cream 5 g intravaginally for 3 days 1

These regimens achieve approximately 80-90% clinical cure rates, equivalent to single-dose fluconazole, though they require multi-day application 1.

When NOT to Use Single-Dose Fluconazole

Recognize complicated vulvovaginal candidiasis, which requires extended therapy 1, 2:

Severe Disease

• Extensive vulvar erythema, edema, excoriation, or fissures require fluconazole 150 mg every 72 hours for 3 doses (total 450 mg over 6 days) 1, 2
• Alternatively, use topical azole therapy for 7-14 days 1

Recurrent Vulvovaginal Candidiasis (≥4 Episodes Per Year)

• Induction therapy: Fluconazole 150 mg every 72 hours for 3 doses OR topical azole for 10-14 days 1, 2
• Maintenance therapy: Fluconazole 150 mg weekly for 6 months keeps 90.8% of women disease-free at 6 months 1, 6
• After stopping maintenance, median time to recurrence is 10.2 months versus 4.0 months with placebo 6

Suspected Non-Albicans Species

• Prior azole exposure or treatment failure raises suspicion for C. glabrata or C. krusei 1, 2
• For C. glabrata unresponsive to oral azoles, use intravaginal boric acid 600 mg daily for 14 days as first-line alternative 1, 2
• Other options include nystatin suppositories or topical flucytosine/amphotericin B combinations 1

Immunocompromised Patients

• HIV, uncontrolled diabetes, or immunosuppression may require extended therapy (fluconazole 150 mg every 72 hours for 3 doses or topical azole for 7-14 days) 1

Critical Drug Interactions and Safety

Before prescribing fluconazole, verify the patient is not taking 1:

• Warfarin: Fluconazole potentiates anticoagulant effect, causing elevated INR and bleeding risk—monitor INR closely 1
• Oral hypoglycemics: Risk of hypoglycemia 1
• Phenytoin: Risk of toxicity 1
• Calcium-channel blockers, protease inhibitors, calcineurin inhibitors (tacrolimus/cyclosporine): Increased drug levels 1

Fluconazole can rarely cause transient transaminase elevations, but baseline liver tests are not required for single-dose therapy in patients without known hepatic disease 1.

Common Pitfalls to Avoid

• Do not treat asymptomatic colonization: 10-20% of women harbor Candida species without symptoms, and treatment is not indicated 1
• Do not assume treatment failure is azole resistance: Azole-resistant C. albicans is extremely rare but can develop after prolonged azole exposure 2
• Do not overlook non-albicans species: If symptoms persist after treatment or recur within 2 months, obtain repeat cultures to identify C. glabrata or other non-albicans species requiring alternative therapy 1, 2

Follow-Up Recommendations

• Clinical cure or improvement should be evident within 5-16 days 1
• Instruct patients to return if symptoms persist beyond 5-7 days or worsen, indicating possible treatment failure 1
• If symptoms recur within 2 months, re-evaluate with repeat wet mount and vaginal culture to guide further therapy 1