What happens when a dog presents with skin lesions at 12 years old... and never had these issues before? Though allergies can start at an older age, don't always assume this is the case. Endocrinopathies, demodicosis, lymphoma... there are other things that need to be ruled out  through a complete history and appropriate diagnostic testing. Check out a quick snapshot on how to approach a senior dog with their first pyoderma.