Tea Tree Oil for Acne, Nail Fungus and Dandruff: What Trials Found
What clinical trials and reviews found for tea tree oil (Melaleuca alternifolia) on acne, toenail fungus and dandruff, with trial sizes, strength of evidence and safety points.
Content last updated . This page has not been medically reviewed.
Safety first. Natural products can cause side effects and interact with medicines. Read essential oil safety before you use anything on this page.
Safety first. Tea tree oil should not be swallowed. Taking it by mouth can cause serious symptoms such as confusion, unsteadiness, inability to walk and coma. [1] If it has been swallowed, call Poison Help at 1-800-222-1222 (US); call 911 for collapse or trouble breathing. Pets are at special risk: see Tea tree oil toxicity.
What this page covers
Tea tree oil is steam-distilled from the leaves of Melaleuca alternifolia, a tree native to New South Wales and Queensland in Australia. [1] NCCIH reports that Aboriginal people of Australia traditionally used the leaves for treating wounds, burns and insect bites. [1] That is traditional use; this page is about research, and the two are kept separate. The trials below tested topical products (on skin, nails or scalp), not swallowed oil. Results for one product do not transfer to another strength or form. For the full oil profile, see Tea tree oil.Research summary
| Use | What the source found | Strength of evidence | Population and form studied |
|---|---|---|---|
| Acne | NCCIH: a small amount of research suggests it might help, but more evidence is needed before definite conclusions. [1] A 2023 systematic review said more evidence is needed to confirm benefits for acne lesions and severity. [2] | Promising but limited | Topical gels |
| Toenail fungus | NCCIH: both the amount and quality of research are insufficient to allow any conclusions. [1] | Insufficient evidence | Topical, 100% oil in one trial |
| Dandruff | One randomized trial reported improvement with a 5% shampoo versus placebo. [3] | Promising but limited (one trial) | Adults and teens, shampoo |
Acne
In a randomized, double-blind trial from a university in Isfahan, 60 people with mild to moderate acne used a 5% tea tree oil gel or a placebo gel for 45 days. [4] The authors reported significantly better lesion counts and severity scores with tea tree oil, and similar, tolerable side effects in both groups. [4] It is a small, short trial from a single site. A 2023 systematic review of randomized trials judged the overall research quality to be poor to modest. [2] A skin clinician can say whether a breakout needs a proven treatment; see Acne.Toenail fungus (onychomycosis)
A trial published in 1994 compared 100% tea tree oil with 1% clotrimazole solution, a standard antifungal, in 117 people with culture-proven toenail fungus, applied twice daily for 6 months. [5] After 6 months the two groups were comparable on culture cure and on partial or full clinical resolution. [5] The culture cure rates were low in both groups (11% and 18%). [5] A 2022 systematic review of alternative treatments for nail fungus found tea tree oil was studied in five of 17 articles and said large placebo-controlled trials are needed before endorsing any of them to patients. [6] Nail fungus is a medical problem that has proven treatments, so a clinician should confirm the diagnosis.Dandruff
In a randomized, single-blind trial in Australia, 126 people aged 14 and older used a 5% tea tree oil shampoo or placebo daily for 4 weeks. [3] The quadrant-area-severity score improved 41% with tea tree oil versus 11% with placebo, and no adverse effects were reported. [3] It is one 2002 trial of one product at one strength. See Dandruff, dry scalp and seborrheic dermatitis.Frequently asked questions
Does tea tree oil work for acne?
Possibly, but the evidence is limited. NCCIH says a small amount of research suggests it might help and more evidence is needed. [1]
Does tea tree oil cure toenail fungus?
The sources do not show that. In a 6-month trial, 100% tea tree oil and a clotrimazole solution gave comparable results, and few people had a culture cure. [5] NCCIH calls the research insufficient. [1]
Does tea tree shampoo help dandruff?
One trial of a 5% shampoo found improvement versus placebo over 4 weeks. [3] One trial is not enough to be sure.
Is tea tree oil safe to put on skin?
Most people tolerate topical products, but redness and irritation occur. [1] The 2023 review found minor effects, except at 25% or higher. [2]
Can I swallow tea tree oil or use it as a mouth rinse?
No. NCCIH says tea tree oil should not be swallowed, and mouthrinses containing it should not be swallowed. [1]
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Limits and what the reviews say
Safety for skin
References
- Tea Tree Oil (NCCIH, National Institutes of Health). https://www.nccih.nih.gov/health/tea-tree-oil. Read 2026-10-23.
- Kairey L et al. Efficacy and safety of Melaleuca alternifolia (tea tree) oil for human health: a systematic review of randomized controlled trials. Front Pharmacol. 2023;14:1116077. PubMed 37033604. Abstract read 2026-10-23.
- Satchell AC et al. Treatment of dandruff with 5% tea tree oil shampoo. J Am Acad Dermatol. 2002;47(6):852-855. PubMed 12451368. Abstract read 2026-10-23.
- Enshaieh S et al. The efficacy of 5% topical tea tree oil gel in mild to moderate acne vulgaris: a randomized, double-blind placebo-controlled study. Indian J Dermatol Venereol Leprol. 2007;73(1):22-25. PubMed 17314442. Abstract read 2026-10-23.
- Buck DS, Nidorf DM, Addino JG. Comparison of two topical preparations for the treatment of onychomycosis: Melaleuca alternifolia (tea tree) oil and clotrimazole. J Fam Pract. 1994;38(6):601-605. PubMed 8195735. Abstract read 2026-10-23.
- Nickles MA, Lio PA, Mervak JE. Complementary and alternative therapies for onychomycosis: a systematic review of the clinical evidence. Skin Appendage Disord. 2022;8(4):269-279. PubMed 35983465. Abstract read 2026-10-23.