Ear Diseases

Contributed by:
Howard A. Mintzer DVM
Mid Hudson and Arlington Animal Hospitals
in the beautiful Hudson Valley of New York State
email: hmintzer@mhv.net

Ear diseases are among the most common reasons for a client to take his pet to the veterinarian. They occur in all breeds and ages of pets. Some types of ear diseases are seen mostly in younger pets while others are more frequent as pets get older. Regardless of the cause they are painful and if untreated can cause serious complications.

Parasitic Ear Disease -Ear Mites

One type of ear disease which is found most often in young pets is caused by the ear mite Otodectes cyanotes. This bug is passed from an infected mother to nursing newborns when their ears open at about 10 days of age. The disease can also be passed from an infected pet to other adult pets. Inside an infected ear thousands of mites are found crawling over a black crumbly mass of mites, mite eggs, dead mites, ear wax, dried blood and other debris. This condition is very, very itchy. Dogs and cats often go into a frenzy of scratching which causes even more damage. Intense scratching pulls the hair off the ear flap, gouges the skin around the ear, and can even cause bleeding in and around the ear. Bacterial infections often complicate an ear mite infestation.

Bacterial and Yeast Ear Infections

The other major type of ear diseases are ear infections. Infections may be caused by a number of different types of yeast and bacteria. Ear infections occur when bacteria and yeast on the skin work their way into a weakened ear canal. The canal may have become weakened and lose some of its ability to fight infection because it became wet (from bathing, or from a swim), because your pet has allergies, because your pet has skin disease, or because the ear canal has become injured from a scratch, insect bite or from various other causes. Any of these factors will weaken the ear's normally strong defense mechanisms and allow an infection get started.

The symptoms that are noticed with these types of infections vary considerably. A mild ear infection might be implied by an ear that constantly fills with wax, no matter how often you clean it. As the disease progresses from mild, to moderate, to severe, pain begins and gradually gets more intense. Your pet may shake his head frequently, stand with his head at a tilted angle, or cry when he scratches his ear. In some cases blood and pus may be shaken out of the ear or a disagreeable odor might be noticed.

Treatment of Ear Infections

The first and most important step in treating an ear infection is to determine its cause. Ear mites can often be seen directly through the otoscope (that instrument we use to look into your pet's ear). The cause of other types of infections are determined by examining a stained ear discharge under the microscope. Once the cause is determined we can proceed with treatment.

Treatment of Ear Mite Infections

We begin with a thorough ear cleaning which allows the medications to reach the bottom of the ear canal where the mites live. This is followed by daily insertion of ear mite medicine into the ears for one week. Since ear mite eggs are also found in between your pet's toes (they get there when he scratches) and at the tip of his tail (cats often sleep with their tail under their head) you need to treat these areas with flea spray or flea mousse once at the beginning and once at the end of the treatment period. Your pet's ears are allowed to rest for one week and then the entire process is repeated over again the following week. One week later your pet should be reexamined to make sure that the treatment was effective.

Treatment of Bacterial and Yeast Infections

As with an ear mite infection, it is of paramount importance that the medications be able to reach the "bug" that is causing the infection. If the ear canal is full of debris, this may be impossible without a thorough cleansing of the canal, either on the examination table if your pet is cooperative and the ear is not too painful, or in surgery with the aid of anesthesia when necessary. If your pet's ear infection is bacterial a sample may be taken at this time and allowed to grow in different antibiotic solutions to determine which antibiotic will be best to use to achieve a cure. The ear canal will be thoroughly cleaned until there are no discharges left to prevent the medications from reaching the infected lining of the canal. Further treatment will take place at home. The treatment you perform at home is very important. If you do not treat your pet's ears adequately, the infection will not go away and your pet will continue to suffer. You will be given more tha! n one solution that will need to b e massaged into the ear canals and perhaps swabbed out. At first it will probably be difficult to clean your pet's painful ear. As the infection gets under control and the ear feels better Fido won't be as resistant to your attempts at treatment. Bacterial infections are also treated with oral antibiotics and occasionally other oral medications.. Please follow the directions on the medicines to give them the best chance to work and clear up the infection.

We routinely recheck ear infections 3 weeks after the beginning of treatment. Seventy-five percent are cured by this time. The remaining cases are usually cured after switching ear medications and treating for another few weeks. Very stubborn cases are often precipitated by disease in other parts of the body. If your pet's ear infection continually reoccurs or is very hard to clear up we may perform some tests with your pet's blood to look for these conditions.

Complications of ear infections

Very few ear infections get better without medical assistance. Left untreated the infection might cause the eardrum to rupture causing a middle ear infection and loss of your pet's balance. This condition is very hard to cure and will probably result in loss of hearing. Continual shaking of the head may cause a blood blister to develop in the ear flap which will need to be surgically corrected. Rarely the infection might travel up the acoustic nerve and cause a fatal brain infection. Even if none of these complications take place, an untreated ear infection continually causes your pet pain. Would you like to be treated this way?


Most cured ear infections never return. Some dogs do seem to be prone to infections, though. These dogs will be helped by using a preventative solution a few times a week. A very important preventative procedure is to make sure the ear canals are dried thoroughly with a drying solution after you bathe your pet or after your pet swims. A pet with allergies (one of the prime causes of ear infections) should be treated for allergy as soon as he starts itching. Even better ask us about medications that might help prevent the allergy!

We know it isn't easy or fun spending all the time and money to treat your pet's ear infection. However remember, the infection is not your pet's fault or your fault. Your pet will love you all the more for your time and concern