Oral fungal infection (commonly called thrush or Candida) can be troublesome for many people with HIV/AIDS (PHAs). Indeed, by one estimate, as many as between 80% to 90% of PHAs may get this complication at some point in their lives. Therapies that can be useful against oral fungal infections include the following:

  • nystatin (Mycostatin)
  • itraconazole oral solution (Sporanox)
  • amphotericin B
  • fluconazole (Diflucan)

A popular therapy is the antifungal drug fluconazole because of its effectiveness, ease of use and relatively few side effects. However, unless the immune system's ability to contain infections is ultimately improved, oral fungal infections will reappear. This often leads to further use of antifungal agents, which in turn increases the risk of the fungus becoming resistant to these drugs. Now there appears to be a plant-based extract, commonly called tea tree oil (Melaleuca), that may hold some promise against oral fungal infections in some people with AIDS.

Researchers in Detroit have been testing mouthwashes containing a very weak solution of tea tree oil. Lab experiments have found that extracts of this plant have activity against some bacteria as well as the fungus (C. albicans) that can cause thrush. The researchers tested two kinds of tea tree oil mouthwashes -- one containing alcohol and the other alcohol-free.

Study Details

Between July 1997 and December 1998, researchers enrolled 27 subjects with AIDS who had the following profile:

  • average CD4+ count: 9 cells
  • all subjects were male
  • all subjects were diagnosed with fungal infection in their mouth and throat

Specifically, the doctors noted the following signs/symptoms and history:

  • All subjects had "creamy, white, curd-like patches" of fungus in their mouth.
  • All subjects had previously been treated with but did not respond to oral fluconazole 400 mg/day for at least two weeks.

Researchers gave 13 subjects tea tree oil mouthwash (Breath-Away brand made by Melaleuca Inc. in Idaho, U.S.) containing alcohol and 14 others the alcohol-free mouthwash, also made by the same company. All subjects were told to swish a small amount of the mouthwash for between 30 to 60 seconds, then spit it out. They were not supposed to rinse their mouths for at least 30 minutes afterward. All subjects were to use the mouthwash four times daily for two weeks. Those subjects whose fungal infections partially cleared after two weeks of using the mouthwash could continue using it for an additional two weeks to see if there was any additional benefit.


Although 27 subjects entered the study, data from two subjects could not be used because of difficulties in adhering to the study protocol. Therefore, researchers could only evaluate data on 25 subjects.

A total of 15 of 25 subjects (60%) responded to the tea tree oil mouthwash in the following way after four weeks:

  • 28% were cured
  • 32% had fewer signs/symptoms

The researchers point out that although response rates at the 4th week were promising, at the end of the first two weeks the response rate was not as good. This suggests that for its effectiveness to be apparent, tea tree oil may need to be taken for up to four consecutive weeks.

In comparing alcohol-based and alcohol-free formulations of the mouthwash, researchers found that both were equally effective. However, the alcohol-based formulation was more irritating. The study shows that tea tree oil mouthwash may be useful for some PHAs who have fluconazole-resistant fungal infections in their mouths.

Caution With Tea Tree Oil

Readers should note that this article mentions a mouthwash derived from tea tree oil. In its pure form, tea tree oil can be very irritating and should NOT be used as a mouthwash.

Clearly, antifungal drugs play a key role in helping to control fungal infections. Two factors not mentioned in the study on tea tree oil which also promote the growth of oral fungal infections are: regular use of antibiotics and nutrition. Regular use of antibiotics wipes out friendly bacteria in the body that helps control yeast. And because oral fungal infections feed off sugar, decreasing the amount of sugar in the diet, together with effective anti-fungal therapy, may be useful. Examples of sources of sugar in the diet include:

  • beer and wine
  • candy
  • products made mostly from white flour (cakes, cookies, muffins, bread)
  • certain sugar-rich fruit such as grapes, grape-juice
  • dried fruit such as raisins and dates
  • sugar-sweetened cereals
  • soft drinks

Reading labels on packaged foods can also be useful as sugar also comes in the form of glucose, fructose and sucrose, all of which are common ingredients used in the processed-food industry.


  1. Vazquez JA and Zawawi AA. Efficacy of alcohol-based and alcohol-free Melaleuca oral solution for the treatment of fluconazole-refractory oropharyngeal candidiasis in patients with AIDS. HIV Clinical Trials 2002;3(4):379-385.