After writing my original blog posts on the subject of cats and essential oils, I still get a lot of questions and they continue to be some of my most popular posts to date. Some information has been or needs to be updated to provide more clarity on the subject matter. So I thought I would create a quick reference guide for those still looking to assuage their fears of using essential oils around their beloved cats. I did a lot of research including contacting my veterinarian as well as the University of Pennsylvania's Vet School for information.
I will say this much--I have a healthy 15 year old cat. He had an unrelated (and expensive) health scare last month and after a battery of blood tests, an MRI, and spinal tap, they concluded that he is very healthy for his age. That said, I use essential oils all the time. I don't diffuse as much as I used to, but I always make sure to not diffuse oils that could be potentially harmful to cats.
Brand does not matter - 100% pure, high quality essential oils can be just as harmful to cats as synthetics.
Essential Oils that can be toxic to cats are Wintergreen, Birch, Basil, Clove, Oregano, Niaouli (Melaleuca Quinquenervia), Thyme ct thymol, Thyme ct borneol, Mountain Savory, Tea Tree, Laurus Nobilis (Laurel) Peppermint, Eucalyptus, and Cinnamon Bark. Other oils can produce health risks for cats that may be for all intents and purposes regarded as safe. The same applies to humans - anyone can have an idiosyncratic reaction to an essential oil or blend.
It has been suggested that cats have an aversion to citrus oils, though there does not seem to be any references to potential toxicity.
Why are some essential oils toxic to cats? "Cats almost completely lack important liver enzymes that humans do possess, and which are important in the metabolism of many essential oil constituents. These are primarily UDP-glucuronosyltransferase (UGT) enzymes such as UGT1A6, UGT1A9 and UGT2B7 (Court 2013, Van Beusekom 2013). " The oils that are most toxic to cats are ones high in Phenols (Carvacrol, Thymol, and Eugenol) Read more on Cats and Essential Oils by Robert Tisserand.
Diffusing essential oils around you cat(s) is generally okay, but as a good rule of thumb, avoid essential oils high in Phenols (listed above), diffuse in a well-ventilated area that they can leave if they do not like the aroma, and always monitor them for any changes in health or behavior like sudden onset of sneezing, coughing, extreme lethargy, vomiting, or disorientation. If a pet has an underlying health problem, particularly a respiratory issue, it may be best to avoid use of essential oil diffusers in the household.
There is a lot of unsubstantiated information on this subject on the internet that does not include legitimate references. When in doubt, consider the source, would you take medical advice from Buzzfeed? You can always check websites like snopes.com or trusted websites and blogs from aromatherapists or industry professionals. I would steer clear from some websites that sell essential oils because they are always going to err on the side of not hurting sales. I have found some of their information confusing and conflicting, on one page they say to avoid essential oils high in phenols with cats and on the next page they are recommending topical use of those oils in some remedies and things like raindrop therapy. That sets off my internal alarms.
What if you use essential oils or blends in your cleaning products? First, they are heavily diluted, but it is always better to err on the side of caution. I have hardwood floors so I use an cleaner with Peppermint and Orange essential oils, vinegar, unscented castile soap, and lavender hydrosol. The only risk would be if a cat would walk across the wet floor and then lick its feet. You can always mop the floor with cleaner and then with warm water to remove any residue.
Applied Zoopharmacognosy FAQ by Caroline Ingraham
Cats and Essential Oils by Robert Tisserand.
Diffusing by Animal Aromatherapy
Essential Oils and Pets by the English Aromatherapist
Essential Oil Safety by Robert Tisserand and Rodney Young