A small tree native to Australia, traditionally used by Aboriginal Australians and brought to global attention by World War II Australian soldiers who carried tea tree oil in their first-aid kits. Modern research backs the topical antimicrobial reputation strongly — tea tree oil is one of the better-studied plant antiseptics. The oil is for external use only.

Topical antimicrobial action against bacteria, fungi, and some viruses
Eases acne — comparable in effect to benzoyl peroxide in clinical research, with less skin irritation
Topical use for athlete's foot, ringworm, and nail fungus
Eases dandruff and seborrheic dermatitis
Used in mouthwashes for gum health, though not for swallowing
Long traditional Aboriginal Australian use for skin infections, wounds, and respiratory complaints (inhaled steam, not swallowed)
Always dilute the essential oil in a carrier oil before skin application — typically 5% to 10%

Active in Terpinen-4-ol, Alpha-terpineol, 1,8-cineole.

Do not swallow tea tree oil — internal use has caused serious toxicity, including coma in children

Topical lavender and tea tree oils have been linked to early breast development in young boys — limit prolonged direct skin exposure for prepubertal children

Common skin irritant when used full-strength — always dilute

Possible allergic skin reactions — patch test before larger applications

Skip during pregnancy beyond modest topical use

Keep out of reach of children — small amounts can be toxic if swallowed

Toxic to pets, particularly cats and dogs — never apply to animal fur or skin

You might also explore

Tea tree