Because their livers are usually unable to metabolize the compounds in these oils, large amounts of these chemicals can lead to liver damage and even death in cats, and there is little to no help for this kind of poisoning.

Careful use of small doses of tea tree oil may not harm a cat's health immediately or in the long term, with lethal doses ranging from about 1.5 teaspoons (7.4 ml) to 3 teaspoons (14.8 ml) for the average cat, and safe doses of about 5 drops (0.4 ml).