INCI: Melaleuca Alternifolia (Tea Tree) Leaf Oil
Essential oil with antibacterial activity against C. acnes. Terpinen-4-ol is the main active component. Acne efficacy confirmed, but irritation is possible.
Topical application
BLimited evidence. One RCT or several controlled studies with limitations.
RCTs showed that 5% tea tree oil gel is slower than benzoyl peroxide but comparable in final efficacy for mild-to-moderate acne. Tolerability is better than benzoyl peroxide.
5% in acne products
Tea Tree Oil (INCI Melaleuca Alternifolia Leaf Oil) is an essential oil from the Australian Melaleuca alternifolia tree. The main active component is terpinen-4-ol (30-48% of the composition). Mechanism. Terpinen-4-ol disrupts bacterial cell membranes, delivering antibacterial action against Cutibacterium acnes, Staphylococcus aureus, Malassezia. Minimum inhibitory concentration against C. acnes is 0.3%, comparable to 2.5% benzoyl peroxide. Where applied. Anti-acne products, especially popular in Body Shop Tea Tree Oil, The Inkey List Tea Tree, Sephora Tea Tree. Concentrations 5-10% in spot treatments. In Spain dermatological brands use it sparingly due to allergenic potential. Evidence base. RCT Bassett 1990 in 124 acne patients: 5% tea tree oil vs 5% benzoyl peroxide showed comparable efficacy over 3 months and better tolerance for tea tree oil. Cochrane review 2015 (4 RCTs) confirmed moderate effect in mild to moderate acne. Safety. CIR and SCCS flagged tea tree oil as a known contact allergen – about 3% of patients react in patch tests. Oxidised oil (over 2 years of storage, exposed to air) is 3-5 times more allergenic than fresh (Pirker 2003). In acne-prone patients undiluted oil may cause irritation and burns. Hormonal-effect controversy. Henley 2007 described three cases of gynecomastia in boys using tea tree oil and lavender products. A subsequent systematic review (Hawkins 2020) questioned the causal link, but manufacturers label products as 'not for children under 12' as a precaution. Pregnancy and lactation – use with caution. Topical use at cosmetic concentrations (up to 2%) is acceptable, but due to theoretical inhalation/absorption neuroactivity dermatologists (Stockton 2018, Murase 2014) recommend avoiding high concentrations (>5%). Alternatives for acne – niacinamide, azelaic acid, sulfur.
Irritation potential
MediumAllergen risk
ModerateThe Evigrade extension adds an evidence panel to Wildberries, Goldapple, Letu, iHerb, Sephora and 12 more stores. This ingredient and every other one in the product show evidence-tier, allergen risk and pregnancy/lactation flags at a glance.
Tea Tree Oil should be used with caution during pregnancy. Consulting a dermatologist or OB-GYN is advisable.
Tea Tree Oil suits: oily, combination. Use with caution in: sensitive, dry.
Tea Tree Oil has moderate irritation potential. Sensitive skin may show a transient reaction that usually settles with adaptation.
Essential oil with antibacterial activity against C.
The INCI name is Melaleuca Alternifolia (Tea Tree) Leaf Oil. It may also appear as: Melaleuca Alternifolia Leaf Oil, Tea Tree Oil.
Published: · updated:
Pregnancy
CautionFor sensitive skin
Oxidized tea tree oil is a potent sensitizer. Do not use old or improperly stored bottles.
Suitable for
Use with caution
5% in acne products