Current Use & What the Science Says?

TTO is currently used for a multitude of skin ailments and infections including acne dermatitis, dandruff, cold sores, scrapes, cuts, burns, insect bites, MRSA, lice, and even toe nail fungus (Carson et. al, 2001; Enshaieh et. al, 2007; Greay, et. al, 2010). With various studies claiming TTO as an antiseptic, antibacterial, antifungal, antiviral and anti-inflammatory agent, it is no wonder that new and upcoming research is looking at the anti-tumour properties of TTO.

A study by Greay et. al (2010) examines the topical use of TTO in order to treat subcutaneous murine tumour growth. More specifically, 10% TTO/DMSO (dimethyl sulfoxide) is tested and analyzed to render proof of in vivo anti-tumour activity. The trial claims topical TTO/DMSO to be a “potentially safe and effective anti-tumour treatment” (Greay, et. al, 2010). This particular formula is the most effective treatment in comparison to the other topical formulas which include: 10% TTO/acetone, 10% TTO/isopropanol, neat TTO, 10% TTO/DMSO and vehicle control-10%H2O/DMSO.

However, despite such positive reviews, the sample population and methods used to perform the study are questionable. First, the study is performed on 25 female mice that are 6-8 weeks old, immune-competent and tumour-bearing. The fact that the study is performed on mice suggests that there is scepticism surrounding TTO as an anti-tumour treatment. Moreover, this suggests that the most successful formulation of TTO treatment is yet to be determined. Furthermore, reasoning as to why only female mice aged 6-8 weeks is used, is not specified. For example, researchers should consider males and older mice in order to reduce variation. In addition, it is stated that 5 mice were assigned per topical treatment.  With no indication of whether or not the mice were randomly assigned renders the possibility of sampling error. Also, if the researchers were not blinded towards the treatments applied to each group of mice, there is a possibility for bias. Lastly, in the trial, treatments were applied once over 4 days. According to Greay et. al (2010), this is a sufficient time period to allow for the regression and growth inhibition of tumours. Yet, there is evidence of 10% TTO/DMSO resulting in temporary skin irritations that clear once treatment ended. Ultimately, because it is the first trial to demonstrate the topical anti-tumour efficacy of a TTO formulation, more testing is required. Nonetheless, the efficacy of TTO as anti-tumour treatment can be proven sound if it is eventually tested on humans (large sample) and is a randomized, double-blinded study.

Another recent study is one that was proposed as a result of conflicting views surrounding the efficacy of TTO to treat methicillin-resistant staphylococcus aureus (MRSA). According to Flaxman and Griffiths (2005), there is “insufficient evidence to support the routine use of tea tree oil in clinical practice for eradication of MRSA colonization”. In response, Thompson et. al (2008), created specific research protocol for a study to compare 5% TTO body wash with a Johnson’s Baby Softwash (standard body wash). Like the previous study, this is the first of its kind. However, the methods used to perform this trial exemplify the appropriate steps needed for valid and sound results. First, the trial is clinical, randomized and controlled. With a large sample size of 224 patients, 41% of those in the TTO group were decolonized from MRSA. Therefore, 5% TTO body wash is a highly successful and effective treatment. Moreover, the trial goes above and beyond, taking into consideration: participant consent, participant withdrawal, potential risk factors and ethics approval. Furthermore, the trial assesses the cost-effectiveness of TTO body wash, evaluates the effectiveness of the PCR assay in detecting MRSA, and monitors each patient’s progress efficiently through consistent swabbing of each patient’s mouth and groin. Overall, this study proves that TTO is an effective preventative treatment for infection.