My dog’s mouth corners are ulcerated and bleeding; what is wrong and what medicine?

From the photo, red, ulcerated, crusted mouth corners may be skin infection, trauma, or oral inflammation. 1. Skin disease: the mouth edge is prone to bacterial or fungal infection, especially when broken; use iodine to disinfect and keep it dry, avoiding greasy food. 2. Allergy: to food, pollen, dust mites, etc.

3. Oral problems: ulcers, gingivitis, or infection can spread inflammation to the mouth edge, often from salty food or poor cleaning causing tartar. 4. Trauma: bites, scrapes, or scratches can cause local redness and scabs.

Seek care early; tests find the cause and a plan with antibiotic ointment, oral antiseptic spray, and mouth care. Keep the mouth clean and dry and avoid further irritation.