Melaleuca alternifolia (tea tree) has been used in aboriginal traditional medicine for wounds and cutaneous infections. Tea tree essential oil has been used to treat several conditions such as empyema, ringworm, paronychia, tonsillitis, stomatitis and vaginal infections. Tea tree oil has been found to be effective in Candida albicans clearance in vaginal infection in experimental models.1

Te tree oil comprises of of terpene hydrocarbons, mainly monoterpenes, sesquiterpenes, and their associated alcohols. It has antiseptic and anti-inflammatory properties and is known for its antimicrobial properties. Tea tree oil is often used as the active ingredient in topical formulations used to treat cutaneous infections. It has antibacterial, antifungal, antiviral, and antiprotozoal activities.2

Tea tree oil shows activity against not only C. albicans, but a range of yeasts, dermatophytes, and other filamentous fungi. Tea tree oil has been shown to be effective in treating Trichomonas vaginalis infections as well.2

A study demonstrated tea tree oil to be effective in eradicating fungal colonization in vaginal candidiasis.3

Tea tree oil’s antifungal actions can be attributed to alteration of membrane properties and compromising membrane-associated functions.4 Tea tree oil alters the permeability of C. albicans cells and inhibits respiration in C. albicans. It also inhibits the formation of germ tubes, or mycelial conversion, in C. albicans.2

In a study evaluating the mechanism of action of tea tree oil and its components against C. albicans, C. glabrata and Saccharomyces cerevisiae, the treatment of C. albicans with tea tree oil and components altered both permeability and membrane fluidity. Tea tree oil inhibits glucose-induced acidification of the external medium for all three organisms in a dose-dependent manner.4

A study assessed the activity of tea tree oil against 81 C. albicans isolates and 33 non-albicans Candida isolates. By broth microdilution method, the minimum concentration of oil inhibiting 90% of isolates for both C. albicans and non-albicans Candida species was 0.25% (v/v). The minimum concentration of oil killing 90% of isolates was 0.25% for C. albicans and 0.5% for non-albicans Candida species. On testing 57 Candida isolates for sensitivity to tea tree oil by the agar dilution method, the minimum concentration of oil inhibiting 90% of isolates was 0.5%. Tests on three intra-vaginal tea tree oil products found the products to have MICs and minimum fungicidal concentrations comparable to those of non-formulated tea tree oil.5

Tea tree oil thus seems to be an effective agent for treating fungal infections, both cutaneous as well as vaginal. It may serve as a beneficial natural therapy in treating vaginal infections during pregnancy.

References

1. Mondello F, De Bernardis F, Girolamo A, et al. In vitro and in vivo activity of tea tree oil against azole-susceptible and -resistant human pathogenic yeasts. Journal of Antimicrobial Chemotherapy 2003;51:1223–9.
2. Carson CF, Hammer KA, Riley TV. Melaleuca alternifolia (Tea Tree) Oil: a Review of Antimicrobial and Other Medicinal Properties. Clin Microbiol Rev. 2006;19(1):50-62.
3. Di Vito M, Fracchiolla G, Mattarelli P, et al. Probiotic and Tea Tree Oil Treatments Improve Therapy of Vaginal Candidiasis: A Preliminary Clinical Study. Med J Obstet Gynecol 2016;4(4): 1090.
4. Hammer KA, Carson CF, Riley TV. Antifungal effects of Melaleuca alternifolia (tea tree) oil and its components on Candida albicans, Candida glabrata and Saccharomyces cerevisiae. Journal of Antimicrobial Chemotherapy 2004;53(6):1081–5.
5. Hammer KA, Carson CF, Riley TV. In-vitro activity of essential oils, in particular Melaleuca alternifolia (tea tree) oil and tea tree oil products, against Candida spp. Journal of Antimicrobial Chemotherapy 1998;42(5):591–595.