Ear infection — Dogs

The story behind the answer

This behavior—repeated head shaking, pawing at one ear, and a head tilt—most often signals an ear infection. Infections inflame the dog’s L-shaped ear canal, causing itch, pain, redness, and a yeasty or foul odor with dark discharge.

Why not the others? Ear mites are uncommon in adult dogs and usually cause dry “coffee‑ground” debris in both ears. A foreign object often triggers a sudden, very acute pain episode after outdoor play, with less odor. Allergic reactions typically affect both ears and come with skin signs elsewhere. Dogs with floppy ears or who swim frequently are predisposed because moisture gets trapped, letting yeast and bacteria thrive. Memory tip: warm, wet, whiffy = infection.