Melaleuca Oil Poisoning

Abstract

A 23-month-old boy became confused and was unable to walk thirty minutes after ingesting less than 10 mL of T36-C7, a commercial product containing 100% melaleuca oil. The child was referred to a nearby hospital. His condition improved and he was asymptomatic within 5 hours of ingestion. He was discharged to home the following day. Melaleuca oil, extracted from the Melaleuca alternifolia, contains 50-60% terpenes and related alcohols. Clinical experience with products containing melaleuca oil is limited. This case report suggests that ingestion of a modest amount of a concentrated form of this oil may produce signs of toxicity.

Melaleuca alternifolia(Tea Tree) Oil: a Review of Antimicrobial and Other Medicinal Properties

“…223:114, 2002). Incidences of oral poisoning in children (55,91,112) and adults (57,133) have been reported. In all cases, patients responded to supportive care and recovered without apparent sequelae.…”

Australian Tea Tree (Melaleuca Alternifolia) Oil Poisoning in Three Purebred Cats

“…2,3,9 Terpinen-4-ol is known to have antibacterial and antifungal properties. 2,3,6,7,9 The allowable level of 1,8-cineole is low because this terpene causes irritation of skin and mucous membranes. 2,3,6,9 1,8-Cineole is also the major component of eucalyptus oil.…”

“…The essential oil of M. alternifolia varies in chemical composition 2,6 but usually contains 50-60% terpenes. The main terpenes, which are regulated by the Australian government, are terpinen-4-ol 2-4,7,9 (minimum 30%) 3,4,9 and 1,8-cineole [1][2][3][4]9 (maximum 15%).…”

“…8 Because it has antibacterial and antifungal properties 4,7,9 and is believed by some to be useful as an antipruritic and an insect repellant, 9 it is currently used in many different products, including pure tea tree oil, gels and body lotions, shampoos, conditioners, balms, liniments, toothpaste, insect repellents, and air conditioner germicides. 2,6 Products that are sold for use on companion animals include shampoos for cats, dogs, ferrets, and horses 2,6,7 and pure tea tree oil products similar to the one used on these cats.…”

“…9 Tea tree oil toxicosis has been reported in humans, rats, dogs, and cats. [3][4][5][6][7][8] Most patients have clinical signs of central nervous system depression. In 1 case, a child who ingested 10 ml of tea tree oil had signs of confusion, disorientation, incoordination, and unsteady gait.…”