Ear Mites in Cats
Ear mite infection is one of the most common health problems seen in cats. Ear mites (Otodectes cynotis) are tiny insects that live in the ear canal and feed by piercing the skin. Mites are prolific. Kittens can be infected by their mothers while still in the nest. Suspect ear mites when both ears are affected.
The most frequent sign is intense itching, characterized by scratching and violent head shaking. This is worse if the cat suffers from an allergic reaction to the mites as well as simple irritation from them. You will see a dry, crumbly, dark brown, waxy discharge when you look into the ears. The discharge looks like coffee grounds and may be foul smelling. Constant scratching at the ears can cause raw areas, along with scabs and loss of hair around the ears. The initial problem may be complicated by a chronic bacterial infection.
Ear mites can be identified by your veterinarian by removing some earwax from a fold or crease with a cotton-tipped applicator and examining it under a magnifying glass, against a black background. Mites are white specks, about the size of the head of a pin, that move.
Demodex cati is another mite that can also affect the ears. Waxy debris is present; the mites can be found by examining a swab from the ears.
Ear mites can leave the ear canals and travel over the body. They are highly contagious among cats, house rabbits, ferrets, and dogs, but almost never humans. If mites are discovered on one pet, all pets in the household should be treated.
Treatment: Ear mites are a serious problem, and are deeply distressing and uncomfortable for your cat. They can crawl deep into the ear canals, where they may be difficult to treat. They can also lead to secondary infections of the ears. It is therefore very important to treat all cases of ear mites promptly and thoroughly.
Do not begin treatment until your veterinarian has positively identified ear mites as the cause of the symptoms. This is because other ear ailments can be complicated by using ear mite medications.
Clean the ears as described below. This is essential. Dirty ear canals contain wax and cellular debris that shelters mites and makes it difficult for ear medications to destroy them.
Medicate the ears using a medication chosen by your veterinarian that is effective against mites. Some common ones are Nolvamite, Mitaclear, and Tresaderm. Follow your veterinarian's instructions for dosage and frequency. It is very important to complete the recommended course of treatment, because a new crop of mites will reinfect your cat if the treatment is stopped too soon.
Ivermectin has been used successfully to treat ear mites. It is given as a single subcutaneous injection or with topical drops into the ear. Selamectin (Revolution) is also sometimes used for ear mites. Demodex cati mites are generally treated with ivermectin or lime-sulfur dips.
During treatment, mites can escape from the ear canals and temporarily take up residence elsewhere on the cat, causing itching and scratching. It is important to treat the entire cat with a topical insecticide preparation, as recommended by your veterinarian. Since most cats sleep with their tail curled up next to their ears, be sure to treat the tail as well.
Clip the cat's nails to minimize injuries from scratching at the ear.
Ear Cleaning Tips
Routine ear cleaning is not required. Some wax is necessary to maintain the health of the tissues. However, ears should be cleaned when there is an excessive amount of wax, dirt, or debris. For small amounts of waxy debris, a damp cotton ball or a cotton-tipped swab works well. Many cats tolerate this well if you sit down and hold them in your lap, facing away.
Do not put any cleaning solution in the ear unless you are confident the eardrum is intact.
To clean a very dirty ear, apply a few drops of warm mineral oil, olive oil, a dilute vinegar solution (three drops white vinegar in 1 ounce [30 ml] of water), or a special ear-cleaning solution from your veterinarian (such as Oti-Clens, Epi Otic, Clear X Cleansing Solution, Virbac, Malacetic Otic, or Tris-EDTA products) to the external ear canal and massage the base of the ear to loosen dirt, excess wax, and debris. Then gently wipe out the ear with a cotton ball.
This article is excerpted from “Cat Owner’s Home Veterinary Handbook” with permission from Wiley Publishing, Inc.
Copyright © 2008 by Delbert Carlson, DVM, and James M. Giffin, MD. All rights reserved.