HI MJ E-
Geez, sounds very similar to what my bully mix goes through. His tends to be localized to his underside though. We’ve come to realize that most of the skin allergies we see with him are a reaction to something in his environment. Maybe the same is true for your dog?
Have you tried eliminating certain items from his inside environment? Like bedding, blankets, things like that that he lays on that could cause some type of contact allergy? A lady I knew found out her dog was allergic to the wool blanket he’d been sleeping on for years. Also washing the dogs bedding in something like All Free Clear instead of something with dyes and fragrances.
However, if hes reacting to something in his environment, but its outside thats a bit harder to manage. Bathing once a week in a medicated shampoo such as https://www.chewy.com/malaseb-medicated-shampoo-dogs-cats-8/dp/119232 or https://www.chewy.com/miconahextriz-shampoo-dogs-cats-16-oz/dp/114184 has really helped our dog. I notice a difference with him when I don’t bathe him regularly, especially in the summer time.
As far as the doctors and testing goes, it definitely does seem like you’ve made a grand effort to get him a diagnosis. Doctors aren’t perfect and sometimes tests aren’t either. However, it does sound like someone at some point lead you astray when they offered you a test for food allergies. I’m assuming (but correct me if I’m wrong) that it was a blood test. Blood tests are by and large infamous for false positives and false negatives and are generally not recognized as a true diagnostic test for food allergies.
While his symptoms don’t sound food allergy related, it doesn’t hurt to rule it out. Since we’ve just started summer in the US, I would get with a regular vet and discuss a food trial. This is the golden standard for ruling in or ruling out food allergies. There are a couple different approaches you can take to what food you choose for a food trial but the end principle is the same. They must eat that food and that food only for the 3 months they are doing the food trial. No treats, no flavored meds, no table food, no nothing. As far as what food you use goes, you can choose to do a homecooked diet of one novel protein and one novel carb for 3 months or you can use a diet from the vet like Royal Canin Ultamino. With Ultamino, the protein source for the food is amino acids that have been extracted from feathers. The proteins molecular weight in daltons is so low (under 1000) that the body’s immune response doesn’t trigger because the molecules are not a threat. Royal Canin actually borrowed this science from human medicine involving babies with allergies to milk.
If after 3 months (and you’ve done the trial correctly) there is no improvement in his symptoms, the idea is that you can effectively say food allergies are not at play. After that you may want to go back to the derm specialist and try the therapy that anon101 suggested. They will basically inject various common/regional allergens under your dogs subcutaneous layer of skin (think of a TB test in humans) and measure the reaction your dog has to each. They will then cocktail together a “vaccine” that you give your dog as a method of desensitizing him to those allergens. It will likely be a lifelong treatment and can cost (at least what I was quoted from LSU vet school) around 200$ for a 6 month supply of the vaccine for your dog. However, results for most pets are usually very good with this course of treatment. It may also be safer and more cost effective depending on the size of your dog than say a drug like Apoquel or an allergy injection like Cytopoint which isn’t guarenteed to work on all pets.
