Yeast (candida) is a normal part of the digestive Flora and, in a healty dog or person, is kept 'under control' by a strong proliferation of the beneficial bacteria. Your dog will have a yeast problem when the necessary bacteria is destroyed by outside factors, most frequently vaccination reactions. That same bacteria, when present in healthy amounts, also accounts for as much as 70% of immune function; therefore, its destruction can desimate much of immune system capabilities.
There are multiple underlying causes for dog skin sores including parasites (fleas, mites), poor grooming, dog skin infection (bacterial pyoderma, fungal), endocrine diseases, skin or hair follicle disorders disorders such as seborrhea, medication side effects (from corticosteroids) and allergy.
Some common causes of itchy skin include: 1  Seasonal and Environmental Allergies â allergies can cause itchy skin along with itching in the nose, throat, eyes and face. 2  Dry Skin â patches of dry skin may be itchy. 3  Eczema â flare-ups of eczema can be very itchy and can occur anywhere on the body.