Expert: Dr. Louis N. Gotthelf - 8/19/2009

Question
My dog is 4 years old and is a Yorkie mix. For his entire life he has had some sort of skin allergy that no vet has been able to identify. He is treated for fleas and I have only seen them on him once and we got rid of them. We have tried oils on his food, food trials, antibiotics and steroids (prednisone and zenequin) oatmeal baths, sulfur baths, benedryl, anti itch creams, antibiotic creams and anything you could possibly think of. Nothing helps. He has to wear a cone collar at all times and cries because he itches so bad. When he scratches he pulls his hair out and causes inflamed or bleeding spots that eventually scab over. We don't know what to do and don't get me wrong I love my dog but he is turning into a million dollar dog and I am on a fixed income. Any suggestions? He is now on a food trial with Eukanuba Venison and Potato food. This is what the vet recommended.

Answer
In this case, the first thing I would do is to treat him with a dip in either phosmet or amitraz to kill any surface parasites that could be causing the scratching. I would also give a shot of ivermectin.

Then I would switch from Prednisone to Dexamethasone.  MAny dogs do not stop itching with low dose prednisone, but a shot of 2mg of dexamethasone will tell you and your vet if there is truly an allergy.  

Food allergy is a definite possibility here, since he had it since he was a puppy.

Of course, skin biopsies will tell your vet the disease process in the dog's skin.