Dog Otitis Externa: Symptoms and Treatment

1 What Is Otitis Externa

It is inflammation of the external ear canal, clinically recognized by severe ear itch, restlessness, hind-leg scratching at the ears, and a distinct foul odor from the ear.

2 Causes

Many factors trigger it. Earwax builds a perfect home for bacteria, especially in dogs with long drooping ears. Bacterial causes include Proteus, Pseudomonas, Staphylococcus, Streptococcus, Clostridium, and E. coli. Fungal causes include Aspergillus, Penicillium, Rhizopus, Malassezia, and Candida. Parasitic otitis is mainly caused by ear mites.

3 Symptoms

The dog shakes its head, itches intensely, and scratches the ear with a hind leg, sometimes causing self-inflicted abrasions and bleeding. The canal holds yellow-brown, foul-smelling discharge, the lining thickens, and the outer fur is stained yellow by the sticky exudate. Untreated, it can deepen into otitis media and suppurative middle-ear disease.

4 Treatment

The aim is to reduce inflammation, relieve itch, remove the cause, and clear debris and moisture. A dog that fights treatment may need sedation. For bacterial infection, clean the canal thoroughly with gentamicin-soaked cotton; for mite-caused infection, use a trichlorfon solution (2 g per 100 ml water) on cotton.

Apply ear-drop oil two to three times daily, or a neomycin, dexamethasone, and lidocaine mix, two to six drops, three to four times daily.

Severely infected dogs may need systemic antibiotics.