Good News for Pets Prone to Ear Infections

Studies support 'old-fashioned' treatment for common problem

Veterinarians may be less likely to prescribe antibiotics and surgery to treat chronic ear infections, thanks to pioneering work carried out at the Ontario Veterinary College with support from OVC Pet Trust.

Otis externa — the inflammation or infection of the outer ear canal — is a very common problem in dogs that can make up 15 to 20% of the caseload at a typical veterinary clinic.

“It is a huge problem,” said Dr. Jan Hall, a professor in the Department of Clinical Studies and dermatology specialist at the OVC Teaching Hospital. “It causes a lot of pain and discomfort for the patient and can be a source of tremendous frustration for owners and veterinarians because it is sometimes very difficult to treat.”

Typically, pet owners and veterinarians will opt for a “quick fix” of antibiotics without first determining the underlying cause. Trouble is, the drugs don’t always work and in stubborn cases, the veterinarian may try a variety of topical and oral antibiotics that in the end only make matters worse, by encouraging the growth of antibiotic-resistant organisms.

“We went back to basics and discovered that the basics work very well,” said Hall.

The “basics” are a variety of simple medical treatments including treating the ears with a mixture of 2% Burow’s solution and 1% hydrocortisone in propylene glycol (BHC) drops.

Burow’s solution was invented in the mid-1800s and used quite effectively in treating ear problems before falling out of favour in the age of modern pharmaceuticals.
Over the past two years, OVC Pet Trust has supported a series of studies to re-evaluate the efficacy of Burow’s solution and compare it to commonly used antibiotics.

Hall is also nearing completion of a study evaluating new treatments for Cocker spaniels with “end stage” ear disease: the point where surgery — involving removal of the infected ear canal — has traditionally been the only option.

“Our philosophy has been to encourage the ear to look after itself and we’ve been very encouraged by the results,” said Hall.

Investing in Discovery

The OVC Pet Trust funds vital programs that enhance the health and well-being of companion animals, such as:

  • Exploring common health problems
  • Developing new therapeutic, diagnostic and surgical techniques
  • Studying the human-animal bond and animal behaviour

Pet Trust funds are distributed annually through two-stage scientific review process. Faculty members from OVC submit proposals for projects with direct relation to companion animal health. CLICK HERE for a summary of some of their current projects.


Phone: 519.824.4120 ext. 54431
Fax: 519.822.2670

OVC Pet Trust
c/o Alumni House
University of Guelph
Guelph, ON N1G 2W1

Prick Up Your Ears
The L-shaped canine ear canal is great for hearing but bad for trapping moisture, parasites and wax that can trigger ear infections.
Floppy-eared breeds of dogs such as spaniels and hounds are the most prone to ear problems. The thickness of the wall of the ear canal is also thought to be a factor in other breeds such as the Sharpei and bulldogs, whose thicker ears seem to make them more susceptible.
Allergies, yeast and bacterial infections are the most common causes of ear problems in dogs while ear mites are the most likely source of infection in cats.
Signs of infection: the pet is repeatedly scratching or rubbing its ears; shaking or holding its head to one side; yellow, brown or black discharge from one or both ears; ears smell bad or are red and tender.