Amphotericin B Vaginal Suppositories for Vulvovaginal Candidiasis
Critical FDA Warning: Amphotericin B Is NOT Indicated for Vaginal Candidiasis
Amphotericin B is explicitly contraindicated by the FDA for treatment of vaginal candidiasis and should not be used to treat noninvasive forms of fungal disease including vulvovaginal candidiasis. 1
The FDA label unequivocally states that amphotericin B "should not be used to treat noninvasive forms of fungal disease such as oral thrush, vaginal candidiasis and esophageal candidiasis in patients with normal neutrophil counts." 1 This is a black-box level warning emphasizing that amphotericin B is reserved exclusively for progressive and potentially life-threatening systemic fungal infections. 1
Guideline-Based Treatment Recommendations
For Candida albicans VVC
The IDSA recommends fluconazole 150 mg every 72 hours for 2–3 doses, followed by maintenance fluconazole 150 mg weekly for up to 6 months for severe or recurrent disease. 2 Single-dose fluconazole (150 mg) is explicitly insufficient for severe or recurrent VVC and should be avoided. 2
For Non-Albicans Species (Especially C. glabrata)
For azole-resistant species, the IDSA advises intravaginal boric acid 600 mg (in gelatin capsules) once daily for 14 days as first-line therapy. 2 An alternative is intravaginal nystatin suppositories 100,000 units daily for 14 days. 2
Research Evidence on Amphotericin B Vaginal Suppositories (Off-Label Use)
Despite the FDA contraindication, limited research has explored amphotericin B vaginal suppositories for refractory cases:
Dosing Regimen from Research Studies
Amphotericin B 50 mg vaginal suppositories nightly for 14 days was used in treatment-refractory non-albicans Candida vaginitis, achieving 70–80% cure rates in women who had failed conventional therapy. 3
Amphotericin B 100 mg vaginal suppositories daily for 14 days (combined with flucytosine 1 g in lubricating jelly base) was used for highly azole-resistant C. glabrata infections with significant clinical and microbiological improvement. 4
Amphotericin B 10 mg (0.01 g) vaginal suppositories nightly for 6 days was used as part of a consolidated therapy regimen for recurrent VVC in a Chinese study. 5
A case report described amphotericin B 100 mg suppositories for successful treatment of Saccharomyces cerevisiae vulvovaginal infection. 6
Clinical Context for Off-Label Use
These studies represent salvage therapy for:
- Non-albicans Candida species resistant to azoles 3
- Highly resistant C. glabrata after multiple treatment failures 4
- Recurrent VVC unresponsive to standard antifungals 5
The medication was generally well tolerated with minimal local side effects in these small studies. 3
Critical Clinical Pitfalls
Never use amphotericin B as first-line therapy for VVC—this violates FDA guidance and exposes patients to unnecessary risk. 1
Confirm species identification and antifungal susceptibility testing before considering any non-standard therapy; culture with speciation is essential for recurrent or refractory cases. 2
Amphotericin B vaginal suppositories are not commercially available in the United States—they require compounding pharmacy preparation, which introduces quality control and availability challenges. 3, 4
Recent evidence shows amphotericin B maintains 95.7% susceptibility against Candida species in HIV-positive women with VVC, supporting its microbiological activity when other agents fail. 7
Practical Algorithm for Refractory VVC
Confirm diagnosis: Obtain fungal culture with species identification and antifungal susceptibility testing. 2
For C. albicans refractory disease: Use extended fluconazole regimen (150 mg every 72 hours × 2–3 doses, then weekly maintenance). 2
For C. glabrata or azole-resistant species: Use boric acid 600 mg intravaginally daily × 14 days (first-line) or nystatin 100,000 units daily × 14 days (alternative). 2
Only if boric acid and nystatin fail: Consider compounded amphotericin B vaginal suppositories 50–100 mg nightly × 14 days as salvage therapy, recognizing this is off-label use contrary to FDA labeling. 3, 4