Tea Tree Oil
Also known as: Melaleuca alternifolia, TTO, melaleuca oil, terpinen-4-ol
Effective Dosage
No established oral dose; topical concentrations vary by application (2-5% for eye/skin use)
What the Science Says
Tea tree oil is an essential oil extracted from the leaves of Melaleuca alternifolia, an Australian plant. It has genuine antimicrobial and anti-parasitic properties — clinical studies show it can reduce bacteria linked to bad breath, help treat eyelid inflammation (blepharitis), kill Demodex mites on eyelashes, and reduce dental bacteria when used as a rinse or irrigation solution. It is used topically or as a rinse only; it is never taken by mouth.
What It Doesn't Do
Won't cure acne on its own — evidence for acne is weak and mostly review-level. Not proven to boost your immune system internally. No evidence it works as a systemic antibiotic. Don't swallow it — tea tree oil is toxic when ingested. Not a replacement for prescription antibiotics or antifungals for serious infections.
Evidence-Based Benefits
Tea tree oil is an essential oil extracted from the leaves of Melaleuca alternifolia, an Australian plant. It has genuine antimicrobial and anti-parasitic properties — clinical studies show it can reduce bacteria linked to bad breath, help treat eyelid inflammation (blepharitis), kill Demodex mites on eyelashes, and reduce dental bacteria when used as a rinse or irrigation solution. It is used topically or as a rinse only; it is never taken by mouth.
Moderate EvidenceEffective at: No established oral dose; topical concentrations vary by application (2-5% for eye/skin use)
Source: auto-research
Absorption & Bioavailability
Unknown for systemic use; designed for topical/local application only. Skin and mucous membrane absorption occurs but systemic levels are not the therapeutic goal.
Red Flags to Watch For
- Tea tree oil is TOXIC if swallowed — even small amounts can cause serious poisoning, especially in children
- Can cause skin irritation, allergic contact dermatitis, or chemical burns if used undiluted or at high concentrations
- Eye products containing tea tree oil can cause temporary discomfort, tear film instability, and conjunctival redness — tolerability varies by formulation
- Not regulated as a drug — product concentrations and purity vary widely across the 1,000+ registered supplement products
- Avoid use near open wounds or mucous membranes without medical guidance
Products Containing Tea Tree Oil
See how Tea Tree Oil is used in these analyzed products:
Research Sources
- PubMed
- NIH DSLD
This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Last updated: 2026-04-09