Already known as an effective natural treatment for head lice, tea tree oil was the subject of two recent studies on other bothersome health conditions – nail fungus and dandruff. Tea tree oil has strong antibacterial, antiviral and antifungal properties.

At the Department of Dermatology at the University of California, a double-blind study was performed to test the effectiveness of tea tree oil on onychomycosis, a common fungal infection of the toenails. Sixty patients with the condition were given either a placebo cream or a cream containing 5% tea tree oil for 16 weeks. At the end of the study, 80% of patients using the medicated cream were cured, as opposed to none in the placebo group. During the follow-up period, the patients who used the medicated cream did not experience a relapse of the condition.

Another skin disorder, dandruff, may also benefit from the antifungal properties of tea tree oil. Dandruff is thought to be caused by a yeast called pityrosporum ovale. In a randomized study at the Department of Dermatology at Royal Prince Alfred Hospital in Australia, 126 men and women with dandruff were given either a placebo or a shampoo that contained 5% tea tree oil. After four weeks of use, the group using the tea tree oil shampoo showed a 41% improvement compared to only 11% in the placebo group. They also reported decreased itchiness and greasiness.

Tea tree oil may be purchased in its pure form or as an ingredient in other products including creams, ointments, shampoos, toothpastes and mouthwashes.

Sources: Trop Med Int Health 1999 Apr;4(4):284-7; J Am Acad Dermatol 2002 Dec;47(6):852-5