"Stinky ear syndrome" and "floppy ears syndrome" are colloquialisms for canine otitis externa. This condition afflicts dogs with large, floppy ears or long ear canals because these anatomical characteristics do not allow for proper ventilation of the ear. An anaerobic environment results, and various yeasts and bacteria proliferate in the ear canal. This process can be very stinky, not to mention very uncomfortable for the dog.

Other than an unusual odor emanating from the dog's ear (or ears, as this condition is often bilateral), clinical signs of canine otitis externa include head shaking and/or tilting, rubbing and scratching the ears, and, in severe cases, hearing loss.

Treatment of bacterial or fungal canine otitis externa depends on its severity. Mild cases may be successfully treated by cleansing the ear with alcohol or another drying agent to discourage further microbial growth. Topical anti-inflammatory and antibiotic medication is used in moderate cases; these ointments must be massaged into the ear canal by gently rubbing the base of the ear in small, circular motions. The treatment of more severe cases includes the addition of oral or intramuscular antibiotics. With proper treatment, a mild or moderate case may resolve in several days.

Prevention of the condition centers around maintaining a dry environment in the dog's ear canal. Regular cleaning of the ears with a drying agent, especially during wet seasons, is recommended; however, excessive ear cleaning may damage the ear tissue and result in inflammation.

A good practice when washing a dog with floppy ears is to put cotton balls in the ear canal to prevent water from accumulating and encouraging microbial growth.