What causes dogs to scratch their ears and bleed

Once your dog is showing frequent ear scratching, consider whether there is an infection inside or outside the ear canal. Then the most common is ear mites. Once there is a case of ear mites, the inside of the ear canal will be more itchy and the dog will show frequent head tossing and accompanied by violent scratching. Secondly: Ectoparasites, such as mange mites, can also cause your dog to scratch. In this case, an Elizabethan collar will be worn to prevent secondary damage.