Tea Tree Oil

© Steven Foster

This fact sheet provides basic information about tea tree oil—common 

names, what the science says, potential side effects and cautions, and 

resources for more information.

Common Names—Australian tea tree oil, tea tree essential oil, 

melaleuca oil

Latin Name—Melaleuca alternifolia

Tea tree oil comes from the leaves of the tea tree and has been used 

medicinally for centuries by the aboriginal people of Australia. Today, 

tea tree oil is often used externally as a folk or traditional remedy for a 

number of conditions including acne, athlete’s foot, nail fungus, 

wounds, and infections; or for lice, oral candidiasis (thrush), cold sores, 

dandruff, and skin lesions.

Tea tree oil is primarily used topically (applied to the skin).

What the Science Says 

• A 2004 NCCAM-funded review examined the ability of tea tree oil to 

kill bacteria and found that in vitro (in a test tube) studies may provide 

some preliminary evidence for the use of tea tree oil as an adjunctive 

(additional) treatment for wounds involving difficult-to-treat bacterial 

infections such as methicillin-resistant Staphylococcus aureus (MRSA). 

However, large, well-designed clinical trials on tea tree oil are lacking, 

and it remains unclear whether tea tree oil is effective against these 

emerging resistant strains of bacteria in people.

• Some smaller-scale clinical studies have had positive results for 

treating athlete’s foot, nail fungus, dandruff, and acne, but more 

large-scale, well-designed clinical studies are needed.

• Tea tree oil may be effective for acne. One clinical trial compared a 

5 percent tea tree oil gel to a 5 percent benzoyl peroxide product for 

the treatment of acne and found that the benzoyl peroxide worked 

slightly better but that the tea tree oil had fewer side effects.
Side Effects and Cautions 

• Tea tree oil contains varying amounts of 1,8-cineole, a skin irritant. Products with high amounts of this 

compound may cause skin irritation or contact dermatitis, an allergic reaction, in some individuals. 

Oxidized tea tree oil (oil that has been exposed to air) may trigger allergies more than fresh tea tree oil.

• Tea tree oil should not be swallowed. Poisonings, mainly in children, have caused drowsiness, 

disorientation, rash, and ataxia—a loss of muscle control in the arms and legs causing a lack of 

balance and coordination. One patient went into a coma after drinking half a cup of tea tree oil.

• Topical use of diluted tea tree oil is generally considered safe for most adults. However, one case 

study did report a young boy who had developed breast growth after using a styling gel and 

shampoo that contained both lavender oil and tea tree oil.

• Tell all your health care providers about any complementary health practices you use. Give them a 

full picture of what you do to manage your health. This will help ensure coordinated and safe care. 

For tips about talking with your health care providers about complementary and alternative 

medicine, see NCCAM’s Time to Talk campaign at nccam.nih.gov/timetotalk/. 

Sources 

Carson CF, Hammer KA, Riley TV. Melaleuca alternifolia (tea tree) oil: a review of antimicrobial and other medicinal properties. 

Clinical Microbiology Reviews. 2006;19(1):50-62.

Carson CF, Riley TV. Safety, efficacy and provenance of tea tree (Melaleuca alternifolia) oil. Contact Dermatitis. 2001;45(2):65-67.

Carson CF, Riley TV, Cookson BD. Efficacy and safety of tea tree oil as a topical antimicrobial agent. Journal of Hospital Infection. 

1998;40(3):175-178.

Halcón L, Milkus K. Staphylococcus aureus and wounds: a review of tea tree oil as a promising antimicrobial. American Journal of 

Infection Control. 2004;32(7):402-408.

Martin KW, Ernst E. Herbal medicines for treatment of bacterial infections: a review of controlled clinical trials. Journal of 

Antimicrobial Chemotherapy. 2003;51(2):241-246.

Martin KW, Ernst E. Herbal medicines for treatment of fungal infections: a systematic review of controlled clinical trials. Mycoses.

2004;47(3-4):87-92.

Tea Tree Oil. Natural Medicines Comprehensive Database Web site. Accessed at www.naturaldatabase.com on May 20, 2010. 

Tea Tree Oil (Melaleuca alternifolia [Maiden & Betche] Cheel). Natural Standard Database Web site. Accessed at 

www.naturalstandard.com on May 20, 2010.

For More Information

Visit the NCCAM Web site at nccam.nih.gov and view Using Dietary Supplements Wisely

(nccam.nih.gov/health/supplements/wiseuse.htm).

NCCAM Clearinghouse

Toll-free in the U.S.: 1-888-644-6226

TTY (for deaf and hard-of-hearing callers): 1-866-464-3615

E-mail: info@nccam.nih.gov

PubMed®

Web site: www.ncbi.nlm.nih.gov/sites/entrez

NIH Office of Dietary Supplements

Web site: www.ods.od.nih.gov

This publication is not copyrighted and is in the public domain. Duplication is encouraged.

NCCAM has provided this material for your information. It is not intended to substitute for the medical expertise and advice of 

your primary health care provider. We encourage you to discuss any decisions about treatment or care with your health care 

provider. The mention of any product, service, or therapy is not an endorsement by NCCAM.

National Institutes of Health

♦♦♦

U.S. Department of Health and Human Services

D459

Created January 2011

Updated April 2012