Tea tree oil can be toxic to cats, especially if the oil is applied without diluting it beforehand, or if the dose is too high. Many veterinarians and other pet care experts recommend not using tea tree oil for cats, although in the past it has been considered a safe and effective remedy for some feline complaints. Tea tree oil is one of the many essential oils, such as peppermint oil, which is considered toxic to these animals. Cat flea shampoos often contain small doses of tea tree oil, but many veterinarians advise buying these shampoos from reputable manufacturers and carrying clearly defined dose information on the package. Cats can easily absorb tea tree oil through their skin and can also be poisoned by inhaling their vapors or swallowing the oil.
Small doses of tea tree oil, applied very carefully, may not cause immediate or long-term damage to the cat’s health. For the average cat, a lethal dose would be between 1.5 teaspoons (7.4 milliliters) and 3 teaspoons (14.8 milliliters). A safe dose would be about five drops (0.4 milliliters), mixed with 1 teaspoon (4.8 milliliters) of vegetable oil or olive oil. The mixture should generally be applied to the cat’s skin, avoiding the eyes, nose and mouth.
Cats are generally considered vulnerable to the toxicity of essential oils because their livers are generally unable to metabolize the compounds present in these oils. Some believe that tea tree oil poisoning can occur even when small doses are applied to the skin, as the toxic compounds in the oil can build up in the liver over time. Some of these compounds include canfene, linalool, alpha-terpinene and terpinolene. Large amounts of these chemicals can cause liver damage and even death in cats, and there is not much you can do with this type of intoxication.
Manufacturers of cat tea tree oil products generally warn that doses of essential oil should be kept very low to avoid problems. Veterinarians and manufacturers generally warn not to apply pure tea tree oil to a cat’s skin because it is usually easily absorbed. Experts also advise not to give tea tree oil to cats orally. Some experts are also concerned about the harmful effects of inhaling tea tree oil and warn that cats, in general, should never be exposed to pure oil.