Chronic Ear Problems (Infections) in Dogs

Overview of Chronic Ear Infections in Dogs

Otitis is an inflammation of the ear and it is one of the most frequent reasons for owners to seek a veterinarian’s help for their dog. The prevalence of otitis externa, or inflammation of the external ear, in dogs has been reported to be between 10 to 20 percent although in more tropical climates it is probably closer to 30 to 40 percent.

The term otitis does not refer to a specific disease, but it is a symptom of many diseases and not a specific diagnosis.

Causes of Chronic Ear Infections in Dogs

Diagnosis for Possible Ear Problems in Dogs

The identification of the underlying disease responsible for the chronic ear disease is of crucial importance. In order to do this it is important for your veterinarian to:

Home Care for Dogs with Ear Problems

Regular cleaning at home is an important part of the therapy. Several products can be used.

More Causes of Chronic Ear Infections in Dogs

Information In-depth on Chronic Canine Ear Problems

Most cases (over 80 percent) of chronic or relapsing otitis externa have otitis media. This results from chronic inflammation of the external part of the ear canal, rupture of the tympanic membrane and establishment of infection in the middle part of the ear.

Discharge in the middle ear cavity is difficult to treat with topical therapy and often remains a source of infection. Otitis media is usually bacterial in origin.

Treatment of otitis media is based on bacterial culture and sensitivity results. Most cases require long term antibiotic therapy (minimum of two months) and aggressive topical therapy.

Most causes of otitis externa are associated with generalized dermatologic conditions. A complete dermatologic history and work-up may therefore be necessary in the diagnosis of many primary otitis externa cases. The most common causes seen in dermatology are atopy (inhalant allergies), food allergy, diseases of keratinization (e.g. primary seborrhea of cocker spaniels), and ear mites. It is critical to long term management of otitis externa that a primary cause can be found.

Diagnosis In-depth for Chronic Ear Infections in Dogs

In cases of ear inflammation, your veterinarian will want to identify and correct the primary underlying cause as well as the perpetuating cause (e.g. bacterial infection).
Diagnosis of atopy is based on history (age of onset, progressive worsening overtime), clinical signs (pruritus on face, feet and ears), exclusion of other pruritic diseases, intradermal skin test, and serology testing for allergen-specific IgE.

Treatment In-depth

Ear cleaning

Thorough ear cleaning is a vital part of the treatment of chronic otitis. The reasons are multiple. The exudate is irritating and provides a good environment for bacteria and yeast to proliferate. In addition, the exudate may inactivate antibiotics and thus cause treatment failure.
When flushing an ear with a ruptured ear drum, the use of saline or 1:1 or 1:3 dilutions of 5 percent white vinegar are recommended. The fluid is discarded with every flush and suck cycle and the canal is filled again with clean saline. This is repeated multiple times using a fair amount of saline. The best results for deep ear cleaning or flushing are obtained with the patient under general anesthesia.Cleaning cannot be done on very swollen, narrowed, ulcerated or painful ears. Such cases need to be treated symptomatically at first and cleaned at a later date when the inflammation has been reduced and the canals have opened. Systemic anti-inflammatory doses of prednisone for 10 days and topical glucocorticoids like Synotic® may be used to decrease inflammation, swelling and pain.

Antibiotic Therapy

Pseudomonas infections are extremely frustrating and difficult to treat. Most effective treatments include:

Antifungal Therapy

Antiparasitic Therapy

Therapy for ear mites can be topical or systemic. Topical treatments include thiabendazole (Tresaderm®) in the ears or selamectin (Revolution®) as a spot on treatment to be applied in between the shoulder blades. Treatment should cover the cycle of the mites, which is three weeks. One single application of selamectin is usually sufficient to eradicate the infestation. Systemic treatment includes the use of oral or injectable ivermectin once every two weeks for three times.

Follow-up for Dogs with Chronic Ear Infections

Cytology and culture should be performed monthly throughout the therapy and before discontinuation of antibiotic therapy. Early identification of the underlying cause and aggressive treatment of the infection are the only ways to prevent more serious and permanent damage in the ear canal.
In hunting dogs, ears should be checked regularly for the presence of foreign bodies. Excessive swimming should be avoided.In breeds with a lot of hair like poodles, gentle hair plucking may prevent the occurrence of infections.