Ear infections are common in dogs, and certain breeds are particularly prone.
Sometimes, we pet owners miss the early signs and do not realize there is an infection until the ears are really angry, painful, and itchy. Fortunately, there are steps we can take to minimize veterinary bills and decrease the frequency of this painful condition. You can also read through our article on how to ease your dog’s pain caused by an ear infection.
Types and Causes of Ear Infection
For the purposes of this article, the types of ear infections are divided into two categories: outer ear infection (on the outside of the eardrum/tympanic membrane) and middle or inner ear infection (on the inside of the tympanic membrane).
Outer ear infections are the most common type, and are typically a result of a damp environment, excessive wax buildup (which traps pathogens), allergies that disrupt the skin barrier, or trauma to the ear. In these cases, the outer part of the ear becomes infected by one or more of the following: yeast (Malassezia sp.), cocci bacteria (often Staphylococcus sp.), and rod bacteria (commonly Pseudomonas sp.).
Inner or middle ear infections occur when a pathogen infects the portion of the ear inside of the tympanic membrane. There are a variety of organisms that can impact these areas (bacteria, yeast, and fungi) and a chronic outer ear infection can lead to development of middle or inner ear infection due to damage to the tympanic membrane and exposure to pathogens.
Signs of Ear Infection
If your dog has ever had an ear infection, you are quite aware of the symptoms: Shaking of the head, scratching with a back leg, rubbing the head on the couch or carpet, redness on the ear flap, and sometimes odor and discharge are signs of an active and uncomfortable infection. Occasionally, a hot spot will also develop on the cheek, due to the trauma from the scratching.
These signs occur when the infection is acute. The affected canal will be red and possibly swollen, may have small bumps, and will likely have a thick dark or yellow discharge that is foul-smelling. There are also more subtle signs that something is wrong. If your dog is holding his head a little to one side, or is mildly lethargic, these can also point to an early infection or inflammation in the outer ear canal.
If your dog has stinky ears, but you are not sure if it is an ear infection, read Dr. Thompson article on what could be causing your dog’s ears to smell. For proper diagnosis of an ear infection, make sure to visit your vet.
Signs of middle and inner ear infections are more serious and include head tilt, walking in circles, anorexia or inability to chew, drooling, nausea, and rapid eye movements from side to side. This is a much more serious condition that requires veterinary intervention and may require a trip to a specialist to properly address.
Diagnosis and Treatment of Ear Infection
Acute outer ear infections are relatively easy to diagnose and treat and will generally resolve quickly once treatment is started. The most common treatment includes cleaning and ear drops. If the infection is caught early or is mild, cleaning your dog’s ears with an over-the-counter cleaner, such as Zymox drops, can resolve the symptoms quickly.
Caution should be exercised when using a cleaner without veterinary examination. If the tympanic membrane is damaged, using an ear cleaner can push the infection into the middle ear, setting your dog up for an even bigger problem later. Most infections require prescription drops that contain a steroid, an antibiotic, and an antifungal agent. This provides rapid relief due to the steroid and is usually curative.
More severe inflammation and longer standing infections will sometimes require an extended course of treatment and possibly oral steroid to bring relief. If the infection is related to allergies, treatment of the underlying allergy may limit recurrence. Food and environmental allergies can both be associated with ear infections, and a step-wise approach to diagnosing and treating allergies is recommended.
Middle and inner ear infections generally require a broad-spectrum oral antibiotic or antifungal. Oral steroid may be of benefit. Treatment may also include symptomatic therapy for nausea and anorexia, but more intensive care may be required for dogs that are severely affected.
Prevention of Ear Infection
As always, prevention is the best medicine. The occasional ear infection (once a year) may not warrant regular preventative cleaning. But if your dog is prone to having outer ear infections, regular cleaning with an over-the-counter product, like Zymox, or a prescription-strength cleaner will be helpful to reduce the recurrence of infection.
In addition, if you are cleaning your dog’s ears weekly, you are likely to notice an infection early. Some breeds, such as cocker spaniels, retrievers, hounds with large ears, poodles and other dogs with hair in the ear canal, are prone to developing outer ear infections. If you own one of these breeds, be vigilant.
Cleaning and drying the ears after swimming and applying a plug of cotton in the entrance to the ear canal before bathing can help keep the canals dry and prevent yeast infection.
Acute and chronic ear infections are a common and frustrating problem for dog owners. If they occur more than once or twice a year, work with your veterinarian to develop a health protocol that will reduce the incidence and severity of this illness. Regular cleaning and observation will help you catch infection early and are recommended.
Remember, your dog cannot tell you exactly what is bothering her, so be watchful and use your senses: 1) Watch for redness, swelling and discharge, 2) Feel the ear for heat and thickening, 3) Smell the ear for a sour or foul smell, 4) Listen for head shaking and scratching, and 5) Taste – well, let’s not go there!
