Well, there are a few things to consider.
Schnauzers cannot only get a seborrheic skin condition, but the breed is predisposed to comedones.
Schnauzer comedo syndrome – believed to be an inherited disorder that causes numerous comedones in the skin of the back of certain schnauzers.
However, there are some other things we need to keep in mind.
results when the thyroid gland does not function adequately. Skin changes are very common.
is a tumor arising from melanocytes, which are the cells that produce pigment. There are benign and malignant variants, both of which must be considered, especially, for the breed.
So, I would start with having all of these areas evaluated by a veterinarian. No different, then a general screening performed by a person's dermatologist.
A blood test for an overall health assessment and to check the thyroid level would be a really good idea as well.
Depending upon the apperance of some of the spots, espeically the larger ones, a small skin biopsy may be indicated.
Either way, in the meantime, I would definitely encourage you to start giving essential fatty acids. Wonderful for the skin.
Your vet should carry a good product, or over the internet you can find Aller G3, EFA-z, or Derm caps.