Overview

Boric acid (BA) is a well-established therapeutic agent for the treatment of various vaginal infections, including recurrent vulvovaginal candidiasis (rVVC) and bacterial vaginosis (rBV).^[1] It addresses microbial imbalances by exerting antifungal, antibacterial, and anti-inflammatory effects. BA works by disrupting the cell wall integrity of yeast, bacteria, and other pathogens, while also modulating the host’s immune response, reducing inflammation, and promoting microbial homeostasis. This multifaceted action supports its validation as a microbiome-targeted intervention (MBTI). BA’s ability to maintain or restore the vaginal microbiome enhances its role in preventing recurrent infections, aligning with the condition’s microbiome signature, which often involves the dominance of pathogenic species such as Gardnerella vaginalis and Candida species.

Validation of Boric Acid (BA) as an MBTI

Boric acid’s molecular mechanisms involve antifungal, antibacterial, and anti-inflammatory effects. It is particularly effective against azole-resistant Candida species and Gardnerella vaginalis, common pathogens in VVC and BV, respectively.^[2] BA acts by altering the pH of the vaginal environment, which inhibits the growth of harmful bacteria while promoting the growth of beneficial Lactobacillus species. This shift in microbial balance is crucial for maintaining a healthy vaginal microbiota. Clinical studies show that BA effectively reduces symptoms of rVVC and rBV and is used as part of combination therapy with antibiotics like metronidazole or clindamycin for BV.^[3] Its effects on biofilm formation and its synergy with other treatments further confirm its therapeutic potential.

Microbial Effects Summary Table

Validation of the Microbiome Signature of Vaginal Infections

The microbiome signature of bacterial vaginosis typically features an overgrowth of Gardnerella vaginalis, reduced diversity, and lower levels of Lactobacillus species. In VVC, Candida species, particularly Candida albicans, are predominant. Boric acid therapy has been shown to target these imbalances, reducing the dominance of these pathogenic species and enhancing the growth of beneficial Lactobacillus and other probiotic microorganisms.^[4] This shift supports the validity of the microbiome signature for both BV and VVC, reinforcing the concept that microbial balance is essential for vaginal health.

Dual Validation

The use of boric acid for treating rVVC and rBV confirms its potential as an effective microbiome-targeted therapy and strengthens the microbiome signature associated with these conditions. By restoring the balance of vaginal microbes, promoting Lactobacillus growth while reducing pathogenic species such as Gardnerella vaginalis and Candida albicans, boric acid directly addresses the microbial imbalances at the heart of these infections. Additionally, its ability to modulate the immune response and reduce inflammation further underscores its role as a targeted intervention for improving long-term vaginal health. These clinical and microbiological effects validate both the intervention and the microbiome signature, demonstrating the therapeutic importance of maintaining microbial equilibrium in treating vaginal infections.

Research Feed

References

1. Clinicians’ Use of Intravaginal Boric Acid Maintenance Therapy for Recurrent Vulvovaginal Candidiasis and Bacterial Vaginosis.. Powell A, Ghanem KG, Rogers L, Zinalabedini A, Brotman RM, Zenilman J, Tuddenham S.. (Sexually Transmitted Diseases 46(12):p 810-812, December 2019.)
2. Boric Acid for the Treatment of Vaginitis: New Possibilities Using an Old Anti-Infective Agent: A Systematic Review. Lærkeholm Müller, Matilde, Damsted Petersen, Christina, Saunte, Ditte Marie L.,. (Dermatologic Therapy, 2024, 2807070, 19 pages, 2024.)
3. Bacterial Vaginosis Biofilms: Challenges to Current Therapies and Emerging Solutions. Machado D, Castro J, Palmeira-de-Oliveira A, Martinez-de-Oliveira J, Cerca N.. (Front Microbiol. 2016 Jan 20;6:1528.)
4. Boric Acid for the Treatment of Vaginitis: New Possibilities Using an Old Anti-Infective Agent: A Systematic Review. Lærkeholm Müller, Matilde, Damsted Petersen, Christina, Saunte, Ditte Marie L.,. (Dermatologic Therapy, 2024, 2807070, 19 pages, 2024.)