What is the recommended treatment for vaginal candidiasis in a healthy adult woman, including options for pregnancy and recurrent infections?

Treatment of Vaginal Candida glabrata Infection

For vaginal Candida glabrata infection, use boric acid 600 mg vaginal capsules once daily for 14 days as first-line therapy, as this non-albicans species demonstrates reduced susceptibility to standard azole antifungals. 1, 2

Why C. glabrata Requires Different Treatment

Candida glabrata is inherently less responsive to azole therapy compared to C. albicans, making standard fluconazole or topical azole regimens inadequate. 1, 2 When symptomatic patients fail to respond to conventional azole treatment, non-albicans species—particularly C. glabrata—should be suspected and confirmed by culture. 1, 2

Diagnostic Confirmation Before Treatment

• Obtain vaginal culture to identify the specific Candida species, as microscopy alone cannot distinguish C. glabrata from C. albicans. 2
• Verify normal vaginal pH (≤4.5) to confirm yeast infection rather than bacterial vaginosis or trichomoniasis. 1, 2
• Confirm symptoms including vulvar pruritus (the most specific symptom), vaginal discharge, soreness, burning, dyspareunia, or external dysuria. 1
• Do not treat asymptomatic colonization, as 10-20% of women harbor Candida species without infection. 1, 2

First-Line Treatment: Boric Acid

Boric acid 600 mg in gelatin capsule intravaginally once daily for 14 days achieves approximately 70% cure rates for azole-resistant vulvovaginal candidiasis caused by non-albicans species. 2

This regimen is specifically recommended by the Infectious Diseases Society of America as first-line therapy for non-albicans Candida infections in symptomatic patients. 2

Alternative Approach: Extended Azole Therapy

If boric acid is unavailable or not tolerated, extended topical azole therapy for 7-14 days may be attempted, though efficacy is substantially lower than for C. albicans infections. 1, 2 Options include:

• Terconazole 0.4% cream 5g intravaginally daily for 7-14 days 1, 2
• Terconazole 0.8% cream 5g intravaginally daily for 7-14 days (extended from standard 3-day course) 1, 2
• Miconazole 2% cream 5g intravaginally daily for 7-14 days 1, 2

Avoid single-dose or short-course (1-3 day) regimens, as these are ineffective for non-albicans species. 2

When Standard Oral Fluconazole Fails

Oral fluconazole 150 mg as a single dose—the standard treatment for uncomplicated C. albicans infection—is inadequate for C. glabrata. 1, 2 Resistance patterns documented in recent studies show C. glabrata isolates demonstrate resistance to fluconazole, ketoconazole, and clotrimazole. 3

If fluconazole has already been prescribed and failed, this strongly suggests non-albicans infection and mandates culture confirmation followed by boric acid therapy. 2

Special Population: Pregnancy

Boric acid is absolutely contraindicated during pregnancy. 4 For pregnant women with confirmed or suspected C. glabrata infection:

• Use extended topical azole therapy for 7-14 days (clotrimazole 1% cream 5g intravaginally daily, miconazole 2% cream 5g daily, or terconazole 0.4% cream 5g daily). 4
• Avoid oral fluconazole at any dose due to associations with spontaneous abortion, craniofacial defects, and cardiac malformations. 1, 4
• Expect lower cure rates (potentially 50-60% versus 80-90% for C. albicans), and consider repeating the 7-14 day course if symptoms persist. 4
• Continue topical azole therapy even when azole resistance is suspected, as boric acid and systemic antifungals cannot be used. 4

Recurrent C. glabrata Infections

For women experiencing ≥4 episodes per year (recurrent vulvovaginal candidiasis):

• Complete a 14-day boric acid induction course to achieve initial remission. 2
• Consider maintenance suppression with boric acid 600 mg intravaginally twice weekly, though this is not formally studied and represents off-guideline use. 2
• Investigate contributing factors including immunosuppression (HIV, diabetes mellitus), recent antibiotic use, or contraceptive use. 3
• Obtain antifungal susceptibility testing to confirm azole resistance and guide therapy. 1

The standard fluconazole 150 mg weekly maintenance regimen used for recurrent C. albicans is ineffective for C. glabrata. 2

Critical Pitfalls to Avoid

• Do not empirically treat with standard azole regimens when C. glabrata is confirmed or strongly suspected based on prior treatment failure. 2
• Do not use nystatin, as it is less effective than azoles even for C. albicans and has no role in C. glabrata treatment. 1
• Do not treat sexual partners, as vulvovaginal candidiasis is not sexually transmitted. 1, 2, 4
• Do not use boric acid in pregnancy under any circumstances, even when azole resistance is documented. 4
• Do not assume treatment failure means non-compliance; persistent symptoms after appropriate therapy warrant culture to identify species and susceptibility. 2

Follow-Up and Reassessment

• Reassess only if symptoms persist after completing the 14-day boric acid course or recur within 2 months. 2
• Obtain repeat culture if symptoms persist to confirm eradication versus reinfection with a different species. 2
• Consider referral to infectious disease or gynecology for women with multiple treatment failures or immunocompromising conditions. 2

Newer Antifungal Options

Two recently developed agents show promise for azole-resistant infections, though availability is limited:

• Ibrexafungerp (FDA-approved) appeared promising in clinical trials for vulvovaginal candidiasis. 1
• Oteseconazole (not yet commercially available) may represent a new option for recurrent infections. 1

These agents are not yet incorporated into standard treatment algorithms and should be reserved for refractory cases in consultation with specialists. 1