Most ear infections are easily and successfully treated. But if left untreated, they could result in serious damage.

Causes
Bacteria or yeast are most often the culprits of otitis externa. Other causes include an accumulation of wax, thick or matted hair in the ear canal, debris, a foreign body, a tumor or impaired drainage of the ear. Sometimes, infections of the external ear canal are a secondary result of some other bodily infection or ear mite infestation.

Otitis media usually results from the spread of infection from the external ear canal to the middle ear. Also, foreign bodies, debris, ulceration or improper ear cleaning can rupture the eardrum and allow infection to reach the middle ear.

Symptoms
Ear infections are very uncomfortable for your pet. Your dog or cat will show his discomfort by shaking his head or scratching at his ears. Often, the ears will become red and inflamed with an offensive odor and perhaps a black or yellowish discharge. If your pet tilts his head constantly, it could be a sign of a middle ear infection.

Diagnosis and Treatment
Because many different culprits can be the cause of your pet's ear infection, it is important to have your cat or dog examined by a veterinarian, who can then determine the proper medication or treatment. Your veterinarian will also make sure the eardrum is intact, as some medications can result in hearing loss if administered to a pet with a ruptured eardrum.

What is involved in an ear exam? Your veterinarian will use an otoscope-an instrument that provides light and magnification-to view the ear canal. He or she will determine whether or not the eardrum is intact and if any foreign material is present. If this is very painful to the pet, sedation or anesthesia may be necessary to complete the exam.

Next, your veterinarian will take a sample of the material in the canal and examine it under a microscope. This is called cytology, and allows the doctor to determine the organism causing the infection. If more than one organism are culprits, multiple medications or a broad-spectrum medication is necessary.

If your veterinarian finds a foreign body, a tick or a very heavy buildup of debris, sedation will likely be required to remove the irritant or to allow a thorough cleansing.

A middle ear infection can be more difficult to clear up. Diagnosis and treatment may include lab tests, X-rays and even surgery. Four to six weeks may pass before the infection disappears, and often during this time you will be told to restrict the activity of your pet.

For both types of infection, you should keep water from entering your pet's ears. Follow-up visits to your veterinarian are very important to make sure treatment is working and the infection has disappeared.

Remember, the longer infection is present, the harder it is to get rid of it. If an ear infection goes untreated, your pet will continue to be in pain. Your pet's head shaking and scratching can cause further problems, such as broken blood vessels that require surgery to correct. Chronic infections can harm the eardrum and close the ear canal. Surgical reconstruction of the ear canal may then become necessary.

Medicating
Treatment prescribed by the doctor usually includes administering medication to and cleaning the ears daily for one to two weeks. Remember, your pet's ears are painful, and Fluffy or Fido might not appreciate what you are about to do, so use caution. Ask your veterinarian for a demonstration on how to treat the ears properly.

Prognosis
Most often, with proper diagnosis and treatment, your pet's ear infection will be cured. However, if ear infections are chronic or recurrent, an underlying problem, such as allergies or thyroid disease, may be the cause.

Because cats are normally resistant to ear infections, other problems should be explored. Your cat may have an unusually shaped ear canal, or its immune system could be suppressed. Have your veterinarian test your cat for the feline leukemia virus and feline immunodeficiency virus (FIV), both of which affect the immune system. Also, diabetic cats tend to be prone to ear infections, so testing for diabetes may be indicated.

Prevention
Pet owners can help their pets avoid ear infections by practicing preventative care at home. This is especially important for those animals that have pendulous ears, have lots of hair in their ears, or have allergies or other medical problems that make them prone to ear infections. A weekly ear cleaning with a veterinarian-recommended ear cleansing solution can minimize or prevent infections. Such a cleaning provides other benefits, as well.

"Weekly ear cleanings get the pet owner to really see the ear on a routine basis, allowing him or her to notice any early warning signs of infection," says AAHA veterinarian Dr. LeeAnn Dumars. "And they get the pet used to having its ears handled, making exams and medication administration easier when necessary."

In addition to ear cleanings, pets with lots of hair on the inside ear flap should have those hairs plucked periodically by their groomer or veterinarian.

"Pet owners with animals that have chronic ear problems must realize that life-long preventative care and maintenance will be necessary to ensure their pet's good health," says Dr. Dumars.