Tea-tree oil, also known as melaleuca oil, is a yellowish colored essential oil that is made from the leaves of the plant Melaleuca alternifolia (native to Australia).
Tea-tree oil and tea oil are completely different products. Tea oil is the sweet seasoning and cooking oil from pressed Camellia sinensis (beverage tea plant), or the tea oil plant Camellia oleifera.
The topical application of tea-tree oil is believed to have beneficial medical properties ("Topical" medications are applied directly onto the skin).
According to the University of Sydney1, "numerous Aboriginal communities along the east coast of Australia have a long history of using tea tree as an antiseptic for skin conditions."
However, despite numerous health claims promoting the antiseptic properties of tea-tree oil, there have been very few high quality trials determining its therapeutic properties. Therefore, much more research is necessary to confirm the potential benefits of tea-tree oil.
Tea-tree oil's uses in medicine
Infected skin wounds - scientists from the University of Wolverhampton, England, found that mixing tea-tree oil and silver greatly enhances their antimicrobial activity while minimizing side effects at the same time.
Acne2 - a comparative study of tea-tree oil versus benzoyl peroxide in the treatment of acne found that "5% tea-tree oil and 5% benzoyl peroxide had a significant effect in ameliorating the patients' acne".
Fungus infections of the nails3 (onychomycosis) - a study published in the journal Trop Med Int Health found that treating toenail onychomycosis with 2% butenafine and 5% tea-tree oil in cream cured 80% of patients.
Athlete's foot4 - the topical application of a tea-tree oil cream for the treatment of athlete's foot (tinea pedis) was examined in a study published in Australas J Dermatol. The researchers said that tea-tree oil cream (10% w/w) appears to reduce the symptomatology of tinea pedis as effectively as tolnaftate.
According to the U.S. National Library of Medicine5, there is insufficient evidence indicating the effectiveness of using tea tree oil to treat:
Risks of using tea-tree oil
Tea-tree oil should never be swallowed, according to the American Cancer Society6, as it can cause severe rashes, blood cell abnormalities, stomachache, diarrhea, vomiting, nausea, unsteadiness, hallucinations, confusion, drowsiness, and even coma.
Allergies associated with tea-tree oil usage
There have been reports of people suffering from allergic contact dermatitis after contact with tea-tree oil. If you developed an allergic skin reaction after using tea-tree oil, avoid using it altogether, dermatologists say.
People allergic to eucalyptol should also be extra careful, as many tea-tree oil mixtures or creams are mixed with eucalyptol.
Side effects linked to tea-tree oil
Topical use of the tea-tree oil may cause severe rash, and reddening of the skin.
People who suffer from eczema or other skin conditions may find that tea-tree oil will exacerbate their symptoms.
In addition, scientists from the National Institutes of Health reported in NEJM (New England Journal of Medicine) (February 2007 issue) that topical use of products containing lavender oil and/or tea tree oil may cause prepubertal boys to have enlarged breast tissue (prepubertal gynecomastia).