Tea Tree EO, cautions
<p>Antimicrobial resistance to broad spectrum Tea Tree oil is easily acquired after repeated exposures. So don't rely on it alone, use periodically.</p>
<p>Not for internal use</p>
<p>A few cases of toxicosis after topical application of high doses of the essential oil to dogs and cats have been reported.
Symptoms included central nervous system depression, weakness, and lack of coordination and muscle tremors that were resolved within 2–3 days after supportive treatment.</p>
<p><a href="http://www.ncbi.nlm.nih.gov/pubmed/9838722" target="_blank">Tea tree oil allergy: what is the offending agent? Report of three cases of tea tree oil allergy and review of the literature.</a></p>
<p><a href="http://www.ncbi.nlm.nih.gov/pubmed/17267908">Prepubertal gynecomastia linked to lavender and tea tree oils.</a></p>
<p><a href="http://www.ncbi.nlm.nih.gov/pubmed/19480554" target="_blank">Cytochrome P450-catalysed arene-epoxidation of the bioactive tea tree oil ingredient p-cymene: indication for the formation of a reactive allergenic intermediate?</a></p>
<p><strong>Adverse reactions</strong>
Allergic contact dermatitis after external application and ingestion of Tea Tree EO has been reported . No adverse reactions were reported in two patch tests using preparations containing up to 5% essential oil. Accidental ingestion of 10 ml essential oil caused confusion, disorientation and loss of coordination in a 23-month-old child . Ingestion of 2.5 ml essential oil by a 60-year-old man resulted in a severe rash and a general feeling of malaise. Induction of a comatose state lasting 12 hours, followed by 36 hours of a semi-conscious state accompanied by hallucinations, was reported in one patient after ingestion of approximately half a cup (120 ml) of the essential oil. Abdominal pain and diarrhea lasting up to 6 weeks were also reported.</p>