Possible environmental or food allergies?
I think my dog is allergic to something, either environmental or food-related. I'd like to figure out which so I can either remove the allergen if it's food related or help him deal with it if it's environmental.
His symptoms are that he's really itchy and has some dark spots on his stomach. The itchiness has gotten a lot better since switching him from Hills Science Diet for large breed puppies (what the vet was feeding him) to Blue Wilderness Puppy; his poops went from runny to firm and he's put on some weight. His treats are chicken-based and grain-free, and the cat food (which he occasionally is able to sample before I can grab him) is also grain-free.
But even with going grain-free, he's still itchy, although it has reduced a lot since switching his food, and he has some dark spots on his stomach (I assume from itching/biting in that area since he does that a lot). I gave him a topical flea medication last week and he had his dose of Sentinel a few days ago, so I don't think it's bugs and I haven't noticed any fleas on him. However, he sneezes a lot when he comes out of his crate in the morning, so I think it could be possibly environmental. One of my dogs had a chicken allergy and she had similar symptoms (super itchy, dark spots on stomach) but she had a very thin coat and didn't put on any weight.
I'm really hoping it's not a chicken allergy, which is why I'm trying to determine any environmental allergies first. Is there any way I can figure out if he's allergic to something in my apartment before going on an elimination diet? I can empathize with him since I'm allergic to my apartment too but I can take medication for it and I don't know what are the medication options for dog allergies. Thanks!