Some dog owners use tea tree oil to treat bacterial and fungal infections on their dog's skin and to restore or maintain skin pH levels. Tea tree oil, also known as Melaleuca oil, is also used for coat care, flea prevention, abscess treatment and to treat arthritis.
It is believed that the use of tea tree oil is safe as long as it is diluted with other benign oils or used in a product that contains a varied of other nonharmful ingredients. This is generally not the case. The amount of tea tree oil that is used in most dog products typically ranges from 0.1 to 1 percent, which is still harmful in most cases due to dogs' sensitivity to the oil.
Although tea tree oil has a number of topical uses for dogs, it is toxic if ingested. The oil contains terpene, which is the chemical that makes it effective against fungi and bacteria. This chemical is also what makes the oil toxic, especially in its undiluted form. Tea tree oil is still very toxic for pets even when it is diluted in some cases because terpenes are absorbed through the skin. In addition to this, many dogs tend to lick their injuries, which causes the oil to be ingested.
The effects of ingestion are seen in the symptoms that manifest, which typically depend on the amount of terpenes that is ingested. Some minor symptoms include excessive drooling or vomiting, while animals that are extremely ill appear weak, have difficulty walking and experience partial paralysis. Life-threatening symptoms include tremors, seizures, reduced consciousness or coma. These symptoms typically manifest two to 12 hours after ingestion or exposure to the toxin.