Ringworm on a Dog’s Ear: What to Know

Ringworm is a fungal skin infection, not a worm. An infected dog may have a patch of hair loss, crusting, scaling, or irritation around the ear, although appearance alone cannot confirm the cause. Spores can remain on fur, bedding, brushes, and other surfaces. Human infection often appears as an expanding, scaly or itchy patch on skin that touched the animal or its belongings. A rash after contact is a presentation of ringworm, but similar changes can also come from eczema, irritation, or another infection.

Avoid sharing the dog’s brushes, bedding, towels, or grooming tools until a veterinarian has assessed the animal. Wash your hands after handling the dog, clean washable fabrics, and avoid scratching any new rash. Do not apply a pet product to your own skin. A clinician can examine the area and decide whether testing or a topical antifungal treatment is appropriate; a more extensive infection may need oral antifungal treatment. Follow the full treatment plan and keep the affected skin clean and dry.

Seek medical advice promptly for a spreading rash, marked inflammation, painful cracks, pus, or involvement of the scalp, face, or around the eye. Arrange assessment sooner if you have reduced immune defenses, diabetes, or close contact with a baby or older adult. Urgent help is appropriate for rapidly worsening swelling, severe pain, fever, or eye symptoms. These warning signs reflect the need to assess complications, not proof that the rash is ringworm.

Ask whether the rash needs a skin sample, which treatment is suitable for its location, and how to prevent reinfection while your dog is being treated. Mention when contact began, which parts of the dog you handled, and any products already used.