http://www.aspca.org/pet-care/dog-care/ear-care

Although a dog’s ears need to be regularly monitored for his entire life, a little basic maintenance is generally all that’s required to keep them clean and healthy.

Canine Anatomy

Because of the twisty, curvy design of a dog’s inner ears, it’s easy for parasites, bacteria and yeast to hide and thrive in them. This also means that any debris in the canal must work its way up to escape. Infections can result from trapped debris. Dogs with allergies are particularly vulnerable, as are those with floppy ears, like Cocker spaniels, basset hounds and poodles.

Routine Care

Your dog’s regular grooming/maintenance routine should include regular ear checks. This is especially important for dogs who produce excessive earwax or have a lot of inner-ear hair:

• If your dog’s inner ears appear dirty, clean them with a cotton ball dampened with mineral oil, hydrogen peroxide or a solution formulated specifically for this purpose. Inner-ear skin is delicate, so allow your vet to demonstrate the proper method for cleaning your dog’s ears.
• Do not clean your dog’s ears so frequently or deeply as to cause irritation, and take care to NEVER insert anything into your dog’s ear canal.
• If your dog sprouts hair from his ear canal, you or your groomer may have to tweeze it out every few weeks to prevent problematic mats and tangles from forming. Please discuss with your vet whether this is necessary for your dog.

Wet Behind the Ears?

If you’re not careful, frequent bathing and swimming can lead to irritation and infection. To prevent this from happening, place cotton in your dog’s ears before baths, and be sure to dry her ears as thoroughly as you safely can after all water sports and activities.

If your dog is prone to ear infections, you might want to pour a tiny amount of an ear drying solution made for dogs into her ear canals to help evaporate any water trapped inside. These ear washes, usually witch hazel-based, are available at better pet supply stores.

Danger Signs

Contact your veterinarian if you notice any of the following symptoms affecting your dog’s ears:

• Ear discharge
• Bad smells
• Redness
• Swelling
• Crusty skin
• Hair loss

Please also be aware that brown or black ear wax—and dry, dark wax resembling coffee grounds—are classic indicators of microscopic ear mites. Only your vet can tell for sure, so please don’t delay bringing a gooey-eared pooch in for a checkup.