Ear mites in cats: how do you spot them and how are they treated?

Ear mites are tiny mites called Otodectes cynotis. They live on the skin of the ear canal, the outer part of the ear, and feed on wax and skin debris. They do not burrow into the skin.

An adult mite is about half a millimetre long, the size of a pinhead. Sometimes you can see one as a white speck that moves, but only just, and it runs away from bright light.

The whole life cycle happens on the animal and takes about three weeks from egg to adult. Adults live around two months and keep laying eggs all that time.

Ear mites are among the most common parasites of cats, and in several studies the most common cause of outer ear problems. Mites can also leave the ear and live on the head, neck, back and tail, where they itch too. That is why vets often treat the whole cat, not only the ears.

The usual signs are a cat that scratches at its ears, shakes its head and rubs its head or ears along furniture or the floor. Both ears are usually affected.

This is what ear mites look like in the ear: dark brown to black wax, dry and crumbly, often compared to coffee grounds, sometimes with a bad smell. It is a mix of wax, blood, skin debris and mite droppings. The ear canal can look red and swollen, and your cat may hold its ears flat or at an odd angle.

Scratching can leave scabs, small wounds or hair loss behind and at the base of the ears. Early on you may only see a bit more scratching, an occasional head shake or a little dark wax.

Some cats with ear mites show few or no signs. How itchy or dirty the ear is does not match how many mites are there, so clean-looking ears do not rule mites out. And the other way round, dark wax is typical but not proof: an infection can look just the same.

The vet looks into the ear with an otoscope (a light with a funnel). Sometimes the mites can be seen as small moving white dots.

Often the vet also takes a swab of the ear debris and looks at it under a microscope. Samples from both ears find more mites than looking alone, and a sample is the step that tells ear mites apart from an infection.

If the ears are very sore, your cat may need sedation so the vet can look properly. The vet also checks the rest of your cat for mites outside the ears and for a secondary bacterial or yeast infection.

When no mites are found but a cat responds well to treatment for mites, vets sometimes take that as support for the diagnosis.

A bacterial or yeast ear infection often gives more, wetter and smellier discharge, with redness, swelling and pain. It can come with mites or on its own. Yeast (Malassezia) lives in normal cat ears and multiplies when conditions change.

Allergy (to food, the environment or fleas) often gives itchy, inflamed ears, and a change in the wax is then usually a secondary infection. Polyps or other growths in the ear canal are rarer, and are found in some cats with long-running ear problems.

A grass seed or other object in the ear often causes scratching on one side only. Plain waxy build-up and a blood blister in the ear flap can also look like mites.

All of these need a different treatment from ear mites and can occur together. So a vet looks first, and often takes a sample, before any medicine goes into the ear.

Ear mites spread by close contact with another animal that has them: cats, but also dogs and ferrets. Cats catch them from fighting, cuddling or sleeping together.

Outdoor cats, strays and cats in colonies, shelters and catteries are more at risk. Where many animals live close together, mites are very hard to control.

Mites do not live long off the animal. Sources differ on how long: from a few days in normal conditions up to months in cool, damp places. Bedding is not thought to be the main route, but washing it is sensible.

Kittens often get ear mites from their mother while nursing. Mites are most common in kittens and young cats, but a cat of any age can have them.

A new cat from a shelter or from outside may already have them. So take a look in the ears in the first days, and keep a cat that seems unwell apart until the vet has checked it.

Not every product suits a young kitten. Severe reactions to ivermectin-type medicines have been reported in very young kittens, and an ivermectin ear gel is not for kittens under 16 weeks old. For kittens the vet chooses the product by age and weight.

Untreated, ear mites cause constant itching. Cats can scratch their ears and the skin around them open. Ear mites usually do not go away by themselves, and animals without signs keep passing them on.

Scratching and head shaking can make blood collect under the skin of the ear flap (an aural haematoma, a swollen ear flap), which needs a vet. Bacterial and yeast infections also often set in on top of the mites and need their own treatment.

In severe or long-running cases the infection can spread deeper to the middle and inner ear, damage the eardrum and affect hearing and balance.

With treatment, the outlook is good. Most cats recover fully once the mites are gone from every animal in the home.

Treatment depends on the cause, so the vet first confirms that it is ear mites. The right product depends on your cat's age, weight and health, how many animals live together and whether the ears are infected too. This page gives no doses: the vet sets the product and schedule for your cat.

Vets often clean the ears first, because wax and debris shield the mites from the medicine. Sometimes a wax-softening cleaner is used, and a very sore ear may be cleaned under sedation.

Many vets use drops on the skin, often at the back of the neck (a spot-on), with an anti-parasite medicine from the macrocyclic lactone family. Active ingredients commonly named include selamectin, moxidectin combined with imidacloprid, milbemycin oxime and ivermectin. These work on mites outside the ears as well. Newer medicines from the isoxazoline family (a tablet or spot-on, such as sarolaner or lotilaner) also work on ear mites. Not every flea product works against ear mites, so the vet chooses. This is information, not a recommendation.

Ear drops or gels are another option. Some contain a mite killer, others only an oily base, and some add an antibiotic, an antifungal or a steroid for swelling and itch. An ivermectin ear gel for cats is not for kittens under 16 weeks old, ears with a damaged eardrum or a fully blocked ear canal.

Most medicines kill the mites but not the eggs. So treatment is repeated or kept up for at least the length of the life cycle, about three weeks, and a recheck is often advised. Itching often eases within a few days, but ear irritation and scratch wounds can take a few weeks to settle. Finish the whole course even when the scratching stops.

Every animal in the home that can carry ear mites (other cats, dogs and ferrets) is usually treated at the same time, even when it shows no signs. Animals without signs are the main source of re-infection.

Each animal gets a product suited to its own species and weight. Some cat products are not safe for dogs, and some dogs, such as collies and related herding breeds, react badly to ivermectin-type medicines. Ask the vet before sharing anything.

Wash beds, blankets and soft toys and clean brushes and combs. Ordinary washing is enough; sprays, foggers and essential oils around the home are not advised. Never use a dog flea product or a household spray on a cat: many contain permethrin, which is poisonous to cats.

Oil in the ear (baby, olive, coconut or mineral oil) is an old home remedy. Some guides say oil can smother mites over weeks, but it needs drops for about a month and the evidence is poor. In a trial, cats given only mineral oil still had high mite counts a month later, and in a small trial, garlic, marjoram and olive-oil drops worked less well than a standard medicine.

Oil, vinegar, alcohol and essential oils can also irritate an inflamed ear and make it worse, and they do not treat an infection. Strong smells can bother a cat's nose too.

Medicines sold without a prescription usually work less well than what a vet supplies, and some are toxic to cats. And if it is not mites, the wrong drops delay the real treatment. The only home step is a gentle clean with a cleaner the vet recommends, alongside the vet's treatment.

A healthy cat ear has little wax, no smell and no discharge. Most cats do not need regular cleaning. Ask the vet to show you how first, especially when the ears are sore.

Use a cat ear cleaner the vet recommends, and warm the bottle in a bowl of warm water first. Lift the ear flap, fill the canal, massage the base of the ear, let your cat shake its head, then wipe away the liquid and loosened debris from the folds you can see with a cotton pad, gauze or tissue.

Give a break with a treat or praise before doing the other ear. Never push anything into the canal: no cotton buds or bulb syringes, and go no further than your finger fits without force. Do not use a cleaner if the eardrum may be damaged, do not over-clean and do not force it if the ear is very painful.

Rarely. Ear mites have been reported in people, but it is very uncommon, and the mites do not crawl from a cat's ear into a person's ear. Some people get a mild itchy skin rash from living with infested animals, and it clears once the pets are treated.

Sources differ in tone: one says no risk, another calls the mite transmissible to people. Good hygiene is enough for most households: wash your hands after ear care. If you have an itch, rash, ear pain or discharge that does not go away, see a doctor and never use a pet product.

Regular flea and parasite treatment from the vet can help prevent ear mites, because some of those products also work on them. Ask which product covers ear mites, because not every flea product does.

Check the ears of new cats and kittens when they arrive, and now and then in cats that go outside. Ear mites often come back if only one pet was treated or treatment was stopped early.