Ask the vet: Dog plagued by ear infections

(Editor’s note: We are adding a new column from Dr. Teresa Hershey, a veterinarian at Westgate Pet Clinic in Linden Hills. Westgate has been treating animals in southwest Minneapolis since 1973. For more details on the clinic, go to If you have a question for Dr. Hershey, email her at

Q: My dog is always getting ear infections.  I treat it with the medication that my vet prescribes, but then the infection comes right back again!  

— Judith

A: Dear Judith,

Chronic ear infections are a very frustrating condition. The most common reason that dogs get recurrent ear infections is because they have an underlying allergy that is setting them up for infection. Unlike people, who tend to get middle ear infections from an upper respiratory infection, dogs most commonly get outer ear infections, more like a skin infection. 

If a dog has an allergy, either to something in his food, or something in the environment, that can create inflammation of the skin. Sometimes dogs will show other signs of skin allergies, like chewing at the feet, or licking the groin and belly area. Other times, it is just the ears that are affected by the allergies. 

The outer ear canal, like the rest of the skin, has some yeast and bacteria that reside there normally. When the skin in the ears gets inflamed, the yeast and bacteria take advantage of this inflammation and start to overgrow, causing an infection.

Veterinarians most commonly prescribe topical medications for ear infections. These topical medications usually have a combination of an antibiotic, an anti-fungal and a steroid in them. The steroid helps reduce the inflammation, and the other ingredients kill the overgrowth of yeast or bacteria. These topical medications take care of most ear infections. 

If the ear infection keeps coming back, however, then taking a closer look at what is causing the inflammation to begin with can be beneficial. Sometimes, a food allergy trial is in order. Often, your veterinarian will want to use a food that contains unique ingredients that your dog’s immune system hasn’t been exposed to previously. Be aware though, of dogs that have allergies, only 10 percent of dogs have food allergies, so a food change won’t always help the ears.

For those situations in which a food change doesn’t help the ears, your veterinarian may prescribe anti-inflammatory medications either orally or topically to be given on a regular basis to help prevent inflammation and hopefully secondary infections. 


Dr. Teresa Hershey

Westgate Pet Clinic