Mild to moderate facial acne is an extremely common disease of teenagers and young adults. This pilot study will investigate whether treatment with a gel containing tea tree oil reduces numbers of acne lesions and improves acne in twenty otherwise healthy consenting participants. The hypothesis is that treatment with tea tree oil gel will result in a significant improvement in acne after 12 weeks of treatment.

Tea tree oil is the essential oil obtained from the Australian plant Melaleuca alternifolia. The oil has been used in Australia for many decades as a topically applied antiseptic and has been used to treat bites, stings, cuts and grazes. Many studies have shown that tea tree oil has both antimicrobial and anti-inflammatory activity in the laboratory. In addition, clinical trials have demonstrated that the oil can help in treating conditions such as dandruff, tinea, colonisation with methicillin resistant Staphylococcus aureus (MRSA) in the nose and acne. Together, these laboratory and clinical studies indicate that tea tree oil can potentially be used to treat relatively minor skin infections or diseases.

This pilot study aims to investigate whether a commercially available gel containing tea tree oil is effective for treating mild to moderate facial acne. A minimum of 18 participants that meet the inclusion and exclusion criteria will be enrolled in the study. Participants will be instructed to apply the tea tree oil gel each morning and night for 12 weeks and their acne will be assessed after 4, 8 and 12 weeks of treatment. Acne severity will be measured by (1) counting the numbers of lesions (pimples) on the face and (2) assigning an overall acne severity score. The lesion counts and severity scores at 4, 8 and 12 weeks will be compared to the baseline count to evaluate whether the acne is improving.

Potential benefits to participants, and of the study, are that their acne may improve as a result of treatment and that the results of the study may provide evidence that a commercially available product is effective for treating acne. There are many over-the-counter topically applied products available for treating acne. Two of the most common active ingredients are benzoyl peroxide and salicylic acid. Benzoyl peroxide is an antibacterial agent that works by killing the P. acnes bacterium on the skin. Although it is relatively effective for treating acne, it can also be quite irritating, especially when patients first start to use it. Salicylic acid acts by helping to unblock pores and remove excess dead skin thus helping pimples to heal more quickly. However, it is generally not as effective as benzoyl peroxide. One previous study has shown that a gel containing 5% tea tree oil performed similarly to benzoyl peroxide for reducing pimples, suggesting that it warrants further study.

Since a small percentage of people (approximately 1.4%) are allergic to tea tree oil all participants will be monitored for any reactions to the study product. Tea tree oil allergy typically manifests as redness and swelling and the site of application. This is one of the possible risks to participants, however, given the small numbers of study participants the likelihood of one or more participants having a reaction to the oil is low. Another possible risk is that participants may not benefit from the treatment and that their acne may not improve.

Inclusion Criteria:

1. Aged 16 - 45 years
2. Mild to moderate facial acne with 10 - 100 lesions
3. Investigator Global Assessment score of at least 2
4. Able to comply with the requirements of the protocol and attend the outpatients clinic at 2, 4, 8 and 12 weeks
5. Able to provide written informed consent

Exclusion Criteria:

1. More than 2 acne nodules
2. Allergy to tea tree oil or any component of the study drug
3. Current skin disease (other than acne)
4. Facial hair that may obscure acne lesions
5. Use of topical or systemic steroids within the last 2 or 4 weeks, respectively
6. Use of topical or systemic antibiotics within the last 2 or 4 weeks, respectively
7. Use of topical acne treatments (eg. benzoyl peroxide, salicylates, retinoids) within the last 2 weeks
8. Use of systemic retinoids within the past 6 months
9. Procedures on the face such as peels, laser therapy or microdermabrasion within the past 4 weeks
10. Women who are pregnant or breastfeeding
11. Women of childbearing potential not using a reliable contraceptive method. Participants taking oral contraceptives must have been taking their current contraceptive for the previous 3 months and must agree to continue with it until study completion.
12. Participation in another clinical trial during the last 12 weeks
13. Concurrent diseases which exclude the administration of therapy as outlined by the study protocol
14. Serious, uncontrolled disease (including serious psychological disorders) likely to interfere with the study and/or likely to cause death within the study duration
15. Chronic lung disease with hypoxemia
16. Myocardial infarction during the last 6 months
17. Non-compensated heart failure
18. Severe non-compensated hypertension
19. Severe non-compensated diabetes mellitus
20. Severe psychiatric disease
21. Known HIV or active chronic hepatitis B or C infection
22. Subjects who, in the opinion of the investigator, are not likely to complete the study for what ever reason.
23. Subjects who, in the opinion of the investigator, abuse alcohol or drugs