Tea Tree Oil & Acne
Tea Tree Oil is the essential oil of the Melaleuca alternifolia, which is a plant native to Australia.[1] While tea tree oil has been used medicinally in Australia for years,(3) it has more recently obtained broader popularity as a natural antimicrobial and antiseptic agent.[2] Evidence of tea tree oil's antimicrobial and anti-inflammatory effects[3] have led to its use in treating acne.
The exact mechanism of tea tree oil's action is unknown. It consists of approximately one hundred compounds, all plant terpenes.[4] These include terpinen-4-ol, which is believed to be tea tree oil's major antimicrobial component.[6] At concentrations between .25% and .5%, tea tree oil is capable of destroying thirty-two strains of propionibacterium acnes (P.acnes), the bacteria most associated with acne.[5] As of yet, there appears to be no evidence of P.acne resistence to tea tree oil.[1]
In a study measuring tea tree oil's effectiveness in treating acne, subjects using a gel containing 5% tea tree oil experienced a reduction in both inflammatory and non-inflammatory acne lesions.[3] Total numbers of comedones, papules, and pustules were each reduced significantly after six weeks of treatment.[3]
In another study comparing a 5% tea-tree-oil gel and a 5% benzoyl-peroxide lotion, tea tree oil also demonstrated effectiveness against both inflamed and non-inflamed acne lesions.[4] Further, the rate of decrease in acne lesions largely paralleled that of benzoyl peroxide after one month, though, in the first month, benzoyl peroxide produced more rapid effects on acne.[4] Study participants using tea tree oil also experienced fewer negative side effects than those using benzoyl peroxide.[4] The study's authors speculated that 5% might be a less-than-optimal concentration of tea tree oil, and that its effects on acne might also be enhanced if used with a keratolytic ingredient.[4]
Like many ingredients in skin products, tea tree oil can cause irritation, particularly at high concentrations.[1] Allergic reactions have also been noted.[6]
References:- 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.
- Koh KJ, Pearce AL, Marshman G, Finlay-Jones JJ, Hart PH. Tea Tree Oil reduces histamin-induced skin inflammation. Br J Dermatol. 2002;147(6):1212-17
- Enshaieh S, Jooya A, Siadat AH, Iraji F. The efficacy of 5% topical tea tree oil gel in mild to moderate acne vulgaris: A randomized, double-blind placebo-controlled study. Indian J Dermatol Venereol Leprol. 2007; 73(1):22-25.
- Basset IB, Pannowitch DL, Barneston RS. A comparative study of tea-tree oil versus benzoyl peroxide in the treatment of acne. Med J Aust. 1990; 153(8):455-58.
- Carson CF, Riley TV. The antimicrobial activity of tea tree oil. Med J Aust. 1994;160(4):236
- Moss A. Tea tree oil poisoning. Med J Aust. 1994;160(4):236