Q: Our Australian-shepherd mix doesn't have fleas, but he scratches constantly and has developed many sores on his body. The vet gives him cortisone shots and then sends us on our way. The cortisone only lasts for a short time and I worry about the long-term effects of these shots. We've tried Benadryl and Chlorotrimeton, which do nothing, and we tried to change the dog's diet. The veterinarian has no further advice. Do you have any ideas? -- K.C., Las Vegas, NV
A: Dr. Cecilia Friberg, a Chicago-based veterinary dermatologist, is concerned about those sores, which may be bacterial or yeast infections triggered by allergies. In any case, they should be treated. Obviously, you need to treat infections, but additionally they can be very itchy. Until you deal with these sores and relieve the itching, there's no way to know if the Benadryl or Chlorotrimeton might actually help the allergies.
Friberg adds, "Steroids are a great choice to treat allergies for short-term relief, as you've learned. Steroids also can diminish the immune system, which may more easily allow for infections to occur. The use of steroids should be carefully controlled."
Apparently, you've ruled out flea allergies. Still, a pet doesn't need to be infested with these pests to develop a severe reaction.
The most likely possibilities for your dog's problem are food allergies or environmental allergies. You mention that you tried to change the dog's diet, but it's necessary to transition to a specific single-protein prescription diet or homemade diet (one specifically recommended by your veterinarian). Those are the only choices for a reliable food trial, and your dog must remain on the new diet for several months, without a scrap of table food or unapproved dog treat. Your veterinarian should oversee the food trial.
If you did go through a proper food trial, then environmental allergy seems the most likely culprit. Since your veterinarian is unsure about the next steps, it might be best to request a referral to a veterinary dermatologist.
Reader question from Tribune Media Services newspaper column, ©Steve Dale, Tribune Media Services