Tea tree oil: Benefits and risks

Tea tree oil has antimicrobial and anti-inflammatory properties, which may help reduce symptoms of some skin conditions. However, it may also irritate the skin and have severe adverse effects if a person swallows it.

Tea tree oil, also known as melaleuca oil, is an essential oil that comes from the leaves of the native Australian plant Melaleuca alternifolia.

Manufacturers may use tea tree oil as an ingredient in cosmetics, topical medications, and household products.

This article discusses the potential benefits and risks of tea tree oil.

There is limited evidence showing that tea tree oil may help treat certain health conditions.

The National Center for Complementary and Integrative Health (NCCIH) advises that research into the effects of topical tea tree oil on people is limited. Topical application means a person applies it to their skin.

Some limited research suggests that tea tree oil may be beneficial for people with acne.

For example, a 2023 review highlighted that tea tree oil has antibacterial, anti-inflammatory, and antioxidant properties. These may help reduce the amount of inflammatory lesions, such as papules and pustules. However, the authors noted that further large-scale, high quality studies on the topic are necessary.

A 2021 study highlighted that tea tree oil has antifungal properties, which means it may help kill fungal pathogens. The authors theorized that it may help treat athlete’s foot, or tinea pedis, alongside antifungal medications. However, they also noted that investigation into the efficacy and safety of this theory is necessary.

A 2023 systematic review noted that in studies from 1992 and 2002, clinical signs and symptoms of athlete’s foot improved in a greater proportion of study participants using tea tree oil in comparison to a placebo. However, the authors highlighted that some of the study participants experienced adverse effects, such as dermatitis, after using the tea tree oil.

Contact dermatitis is a form of eczema due to contact with an irritant or allergen.

An older 2011 study compared several treatments for contact dermatitis, including tea tree oil, zinc oxide, and clobetasone butyrate, which is a steroid cream. The results suggested that tea tree oil was more effective in suppressing allergic contact dermatitis than other treatments. However, it did not affect irritant contact dermatitis.

However, people need to remember that tea tree oil may induce allergic contact dermatitis or skin irritation in some individuals.

An older 2002 study suggested that mild to moderate dandruff relating to the yeast Pityrosporum ovale may be treatable with 5% tea tree oil.

Study participants with dandruff who used a 5% tea tree oil shampoo daily for 4 weeks showed significant improvements in overall severity and itchiness, scaliness, and greasiness levels in comparison with a placebo. The participants experienced no negative effects.

Older 2012 research compared tea tree oil and nerolidol — a natural compound in some essential oils — in the treatment of head lice. The tea tree oil was more effective at killing lice, eradicating 100% of them after 30 minutes. On the other hand, nerolidol was more effective at killing the eggs.

Combining both substances, at a ratio of 1 part to 2, worked best to destroy both the lice and the eggs.

Doctors may refer to fungal nail infections as onychomycosis.

A small 2020 study analyzed participants across 12 months of using a topical antifungal treatment containing vitamin E and tea tree, lime, and oregano essential oils. In the results, 78.5% of the 20 individuals experienced a complete cure of the condition.

However, a 2024 review suggested that, overall, there is weak evidence to support the use of tea tree oil to treat onychomycosis. The authors noted that larger clinical trials are necessary to establish the safety and efficacy of tea tree oil.

A small 2020 study found that tea tree oil mouthwash was slightly more effective than chlorhexidine mouthwash in treating gingivitis. However, the authors noted that further research into the efficacy of tea tree oil as a mouthwash is necessary.

People need to note that tea tree oil can cause serious adverse effects if they swallow it.

Applying tea tree oil topically or ingesting it carries several risks.

A person always needs to speak with a doctor before using any essential oils, including tea tree oil.

People should never swallow tea tree oil as it can cause symptoms such as:

People may sometimes develop allergic contact dermatitis after using topical products containing tea tree oil. If they experience allergic contact dermatitis or skin irritation symptoms, they need to stop using these products.

Symptoms may include:

People also need to dilute pure tea tree oil with a carrier oil, such as sweet almond or coconut oil, before applying it to the skin to help prevent irritation.

Although research suggests essential oils may have some health benefits, it is important to remember that the Food and Drug Administration (FDA) does not monitor or regulate the purity or quality of these oils. A person should talk with a healthcare professional before using essential oils and research the quality of a particular brand’s products. It is also important to always do a patch test before trying a new essential oil.

Tea tree oil has some medicinal properties that may be useful for treating conditions such as acne, contact dermatitis, and athlete’s foot.

However, research is limited, and further studies are necessary to determine whether tea tree oil is safe and effective for treating medical conditions.

Additionally, a person should never swallow the oil, as it can cause severe side effects. Tea tree oil may also cause skin irritation in some individuals.

A person always needs to contact a doctor before using essential oils.