Essential oils and cats

Why cats and not dogs

Cats have a limited version of the glucuronidation pathway the liver uses to clear many plant compounds. What a person or a dog processes without noticing builds up in a cat. That single difference is why every serious guide treats cats as a category of their own, and why this page exists separately from the dog guide.

The ASPCA describes the effects of significant exposure as gastrointestinal upset, central nervous system depression and liver damage. Texas A&M's veterinary school has published the same warning specifically about diffusers.

The list, and the common notes on it

The ASPCA names oil of wintergreen, oil of sweet birch, citrus oil (d-limonene), pine oils, ylang ylang, peppermint, cinnamon, pennyroyal, clove, eucalyptus and tea tree.

Twelve common household notes fall on that list: Grapefruit, Sweet Orange, Lemon, Tangerine and Bergamot as citrus oils, plus Pine Needles, Ylang Ylang, Peppermint, Cinnamon, Clove, Eucalyptus and Tea Tree. Wintergreen, sweet birch and pennyroyal are the three worth avoiding outright.

We publish that rather than bury it, because a cat owner who finds out later finds out the expensive way.

Passive and active are different questions

This distinction decides most of the answer:

• Passive — a reed diffuser, or a tealight oil warmer. No droplets of oil leave the device. Unless oil reaches the cat's coat or is licked, the hazard is respiratory irritation.
• Active — ultrasonic and nebulizing diffusers, ours included. These put real microdroplets of oil into the air. They are small, they are still oil, and they land on surfaces and on fur — where a cat then grooms them off and swallows them.

That last step is the one people miss. With an active diffuser, inhalation is not the only route; grooming turns airborne oil into an oral dose.

How to run one anyway

For a household with a cat, the workable version is narrow but real:

1. A room the cat can leave, with a door open and airflow. Never a closed room.
2. A set period — thirty minutes to two hours, not continuous, not overnight.
3. A note that is not on either list — chamomile, cedarwood, sandalwood, frankincense and vetiver. Lavender is the trap here, and it gets its own section below.
4. Bottles capped and out of reach. Ingestion is the severe case; a knocked-over 10 ml bottle is worse than a week of diffusing.
5. Never on the cat. Not diluted, not "a drop for fleas", not on bedding the cat sleeps on.
6. Not at all if the cat has asthma or any breathing condition.

If that sounds like too much bookkeeping, use a warmer instead, or scent a room the cat does not use.

Lavender is the one everybody gets wrong, including us at first

Search this question and you will be told lavender is the safe choice for a home with a cat. That answer comes from reading one ASPCA page and not the other.

• The ASPCA's article on essential oils names eleven oils. Lavender is not among them.
• The ASPCA's toxic plant database lists Lavandula angustifolia as toxic to cats, dogs and horses, with linalool and linalyl acetate as the toxic principles and vomiting, nausea and loss of appetite as the signs.

Both pages are the ASPCA. They are answering different questions — one about concentrated oils reported to poison control, the other about the plant and its compounds — and lavender falls between them.

Our position is the stricter reading: treat lavender as one to be careful with around cats, not as the safe default. It is the note with the best sleep evidence for humans, which makes it tempting, and that is exactly why it needs saying out loud.

What a reaction looks like

Watery eyes or nose, drooling, vomiting, wobbliness or an unsteady gait, lethargy, difficulty breathing, or a burning sensation that shows as pawing at the face. Signs can appear from inhalation as well as from swallowing.

If you see them: move the cat to fresh air, do not try to wash oil off with anything oily, and call your vet or the ASPCA Animal Poison Control Center on (888) 426-4435.

The honest bottom line

We sell an ultrasonic diffuser. In a home with a cat, an ultrasonic device is the thing we sell that needs the most care — and for some households the right answer is not to buy one. We would rather write that here than find it out from a support email.

Read next

• Cats, dogs, babies: what to diffuse and what to skip — the same question for dogs, children and open flame.