Nystatin for Vaginal Yeast Infections
Nystatin is effective for treating vaginal yeast infections but is inferior to topical azole antifungals (clotrimazole, miconazole) and should be reserved as a second-line option, particularly for azole-resistant cases or recurrent infections caused by non-albicans Candida species. 1, 2
Why Azoles Are Preferred Over Nystatin
Topically applied azole drugs are more effective than nystatin for vaginal candidiasis, achieving symptom relief and negative cultures in 80-90% of patients who complete therapy. 1
The CDC explicitly states that azoles outperform nystatin in treatment efficacy, which is why nystatin requires a longer 14-day treatment course compared to 1-7 days for most azole regimens. 1
Comparative studies confirm that while nystatin achieves cure rates of approximately 78%, it has significantly higher relapse rates compared to azole antifungals like miconazole and clotrimazole. 3
When Nystatin May Be Appropriate
Nystatin demonstrates particular effectiveness for recurrent vulvovaginal candidiasis (RVVC) caused by C. glabrata (64.3% cure rate) or fluconazole-resistant Candida species, where it may outperform oral fluconazole. 4
For patients who have failed azole therapy or have documented azole-resistant infections, nystatin 100,000-unit vaginal tablets for 14 days represents a viable alternative. 1, 4
Critical Prescribing Details
Important caveat: The FDA-labeled nystatin cream formulation is NOT indicated for intravaginal use—only the vaginal tablet formulation (100,000 units) should be used for vaginal candidiasis. 5
The standard nystatin regimen is one 100,000-unit vaginal tablet daily for 14 days, which is considerably longer than the 1-7 day courses typical of azole therapy. 1
Oil-based vaginal preparations may weaken latex condoms and diaphragms, requiring counseling about barrier contraception during treatment. 1
Recommended Treatment Algorithm
For uncomplicated vaginal candidiasis (first-line):
- Use topical azoles: clotrimazole 1% cream for 7-14 days OR miconazole 2% cream for 7 days OR single-dose oral fluconazole 150 mg. 1, 2
For recurrent or azole-resistant cases (second-line):
- Consider nystatin 100,000-unit vaginal tablets for 14 days, particularly if C. glabrata or fluconazole resistance is suspected. 1, 4
For severe or complicated cases:
- Multi-day azole regimens (7-14 days) remain preferred over nystatin due to superior efficacy and lower relapse rates. 2, 3
Follow-Up Considerations
Patients should return only if symptoms persist after completing treatment or recur within 2 months of initial symptoms. 1, 2
Treatment of sexual partners is not routinely recommended for vulvovaginal candidiasis but may be considered in women with recurrent infections. 1
Premature discontinuation of nystatin's 14-day course can lead to treatment failure, so emphasize completing the full regimen even if symptoms improve early. 6