Tea tree oil is a wonderful addition to the armamentarium of natural products to fight acne. It is an essential oil that is steam-distilled from Melaleuca alternifolia leaves, native to Australia. The leaves were used in the past as a substitute for tea, giving it the name “tea tree oil”. Oil from leaves is used medicinally for its antibacterial, antifungal, antiviral and antiseptic properties.
The tea tree is a tall shrub growing along streams and on swampy flats in New South Wales. Its leaves are linear, 10 mm to 35 mm long and 1 mm wide, giving it its other name “Narrow-leaved Tea Tree”.1 Tea tree oil is a clear to very pale golden hydrophobic essential oil with a fresh camphoraceous odor. It’s been used in Australia for centuries. Australian aboriginals crushed the tea tree leaves and applied them to their skin to heal skin cuts, burns and infections. The indigenous people of eastern Australia inhale the oils from the crushed leaves to treat coughs and colds, and soak the leaves to make an infusion to treat sore throats.
Arthur Penfold published the first reports of its antimicrobial activity in the 1920s and 1930s, stating its antimicrobial activity is 11 times stronger than phenol. Subsequently, the commercial tea tree oil industry was born. With a resurgence of interest in natural products in the 1970s, commercial plantations were established, leading to large-scale production of a consistent essential oil product.2
Today tea tree oil is used for many dermatologic conditions, including acne, athlete’s foot, boils, dandruff, eczema, lice, psoriasis and as an antiseptic. It is also used for thrush, yeast infections and periodontal disease.3 Tea tree oil has been shown in studies to have activity against Staphylococcus aureus including Methicillin-resistant Staphylococcus aureus (MRSA), multiple dermatophytes,, Malassezia furfur (the most common cause of dandruff), candida, herpes virus and the scabies mite.4
Applying topical tea tree oil to acne lesions has been found to kill Propionibacterium acnes, the bacteria on human skin involved in causing acne. In 1995, Researchers found tea tree oil and its components, terpinen-4-ol, alpha-terpineol and alpha-pinene, to be active against Propionibacterium acnes. A study published in the Letters in Applied Microbiology found the use of tea tree oil was effective in the treatment of acne, and terpinen-4-ol was not the sole active constituent of the oil.5
In 2002, a study of 27 volunteers found tea tree oil reduced histamine-induced skin inflammation.6 Patients were injected intradermally in each forearm with Histamine diphosphate, and flare and weal diameters and double-skin thickness were measured every 10 minutes for one hour to calculate flare area and weal volume. After 20 minutes, 25 ul of 100-percent tea tree oil was applied topically to the study forearm of 21 volunteers, and 25 ul of paraffin oil was applied to six volunteers as a control. Researchers reported application of liquid paraffin had no significant effect on histamine-induced weal and flare; however, mean weal volume significantly decreased 10 minutes after tea tree oil application.
In 1990, a single blind, randomized trial conducted in Australia compared the effectiveness and tolerance of 5-percent tea tree oil gel with 5-percent benzoyl peroxide lotion in 124 people with mild to moderate acne.7 Subjects in both groups had a significant reduction in inflamed and non-inflamed acne lesions (open and closed comedones) over the three-month period. Tea tree oil was less effective than benzoyl peroxide and took longer to work initially; however, subjects reported fewer side effects with tea tree oil. In the benzoyl peroxide group, 79 percent of people had side effects, including itching, stinging, burning and dryness.
Additionally, in 2007 a randomized, double blind, placebo-controlled study determined the efficacy of 5-percent topical tea tree oil gel in mild to moderate Acne vulgaris in 60 subjects.8 In terms of both total lesion count and acne severity index, tea tree oil gel was 3.55 times and 5.75 times, respectively, more effective than placebo. Side effects with both groups were tolerable and very similar.
Undiluted tea tree oil may cause skin irritation, redness, blistering, over-drying and itching when applied directly to the skin. Tea tree oil should not be taken internally, even in small quantities. The tea tree oil in commercial toothpastes and mouthwashes is generally considered to be acceptable because it is not swallowed. Warnings should be on all containers not to use tea tree oil if you are pregnant or breastfeeding, and keep tea tree oil out of the reach of children and pets.
Pure, undiluted tea tree oil is found in health food stores and online. Tea tree oil is also an ingredient in a number of commercial products ranging from face washes to skin care lines. Australian tea tree oil is another natural exotic that is a great addition not only to acne therapies, but also for many other cosmetic and dermatologic applications.
Jeanette Jacknin, M.D., (JJMDSkinCare.com and DrJacknin.com) is a board-certified dermatologist. She is a well-respected physician, entrepreneur and author with a passion for nutricosmeceuticals and holistic dermatology. Dr. Jacknin’s is the author of, “Smart Medicine for Your Skin”, published by Penguin Putnam. She is available for consultation. Contact her at [email protected].
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