This is Dr. Christian.
Thank you. That helps me understand what's been done up to this point. The nizoral is for skin yeast infections probably. The hydroxyzine is an antihistamine to help with allergies. The prednisone is a steroid that helps with allergies and itching. Certainly your dog appear to have allergies. He has all the symptoms (itching, irritation and skin infections). Atopic dermatitis is a common skin allergy that basically means the source of the allergy is currently unknow. Common allergens are all types of grass and trees, pollen, and dust. The only way to know for sure what he is allergic to is to have allergy testing done. After it is known what he is allergic to then a series of shots can be prescribed over several months to reduce the symptoms of allergies. It is not always 100% effective but when if successful then long term steroid (prednisone) therapy is not necessary. Prednisone can eventually lead to many different health problems such as weight gain, liver disease and diabetes so the goal is to use it as little as possible. A short course of steroids to get things under control is usually fine. The problem with allergy testing and the shots is that they can be expensive and in some cases don't work. You can discuss allergy testing with your veterinarian if you are interested in that route. Another possibility in this case is food allergy. It will typically cause itching feet and ear but can affect any part of the body. He can eve react to the Wellness. The quality of the food doesn't matter with food allergies, only the ingredients. Food allergy can be difficult to diagnose. He can develop the allergy at any point in his life to any part of his food, even if he has been eating the same food all along. Common allergens are corn, wheat, beef, chicken, and whey. I would consider switching himto a prescription diet. These diets are made specifically for food allergies. I'm sure your vet can prescribe one of these diets. Examples include Science diet z/d (one of my favorites), and royal canin IVD. The key is strict control of what your dog eats. The diets can take 4-10 weeks to actually work so you'll have to be patient. In addition, he cannot get any other foods at all, including treats. If he is reacting to treats it will look like the diet is not working and you've wasted your money on a prescription food. If after 10 weeks the itching has not improved then it's probably not food allergy. If the itching is better then you can add one treat back in to his diet. If he starts reacting again then you know to never feed that treat again. The prescription diets are more expensive but in many cases are worth it to avoid constant and miserable itching.
As for over the counter medications, none of them will be nearly as effective as the steroids and nizoral. Benadryl can sometimes be used but is only effective in milder cases and sometimes doesn't even work. The prednisone is much better. Here are some other things you can try to reduce itching:
If you have more questions please let me know.