How old is your dog?
I'm gonig to tell you a story about one of our rescue dogs.
He is a Saint Bernard and was owned by my brother n law which did not feed him like he needed. His wife didn't feed him at all. They had another dog, a chocolate lab that had some kind of neuological problem. He would twitch so bad he could hardly walk. They didn't now what it was because this dog never saw the vet. Anyway. Beauregard was growing fast and required more food. Both the large dogs where fet 1 cup of food and left to fight over it. He was given no training either and loved to jump on people. WE finally talked them out of him after he was 6 months old and skin and bones and he had a terrible itching problem, ws loosing his hair and had a stench aobut him nobody wanted to touch him. It was awful, sickining, absolutely discusting. He had bloody spots wverywhere he could scratch at. First of all we tried worming him. That made him feel better and had the energy a puppy is suppose to have but didn't take care of his scratching. I did some research on Saints and discovered they have to have special food. The best for him that we could afford was Pedigree for Large breeds. I also made him a mixture I called gravy that had oatmeal, eggs and either meat gravy thickened with the oatmeal or chicken broth thickened with the oatmeal. this was mixed everyday in his food. He started to gain weight but still had the itching and bad smell. I was told by somebody that it could be mange but none of my other dogs had the itching problem. Then discovered there is a mange that is passed from mother to puppies and isn't contagous but has the same symptoms as what he had. So off to the vet. We had him for 6 months trying to do what we could. Neither of us had a job so a vet visit wasn't in the budget. But I called them and made arrangements for a payment schedule and off we went. They did the mange test and came to the conclusion that he was having an allergic reaction to something and the smell was a skin infection from the sores that never heald by all the scratching. He was given an antibiotic shot and pills to take everyday for a month and Predizone for the itching. That did the trick. The itching stopped and the smell is gone. Now that it is spring, the itching has started again. So I know it isn't a food allergy. Maybe a respitory allergy because we have a yard full of flowers and plants of all kinds. We cna't give him the predizone right now because he is scheduled for surgery this thursday. He is getting fixed and the Predizone slows healing so after he is healed he will be back on the predizone. It only costs ten buck for a months supply.
We have 4 dogs total and a grandson and lots of chickens to feed. A trip to the vet is a huge expense we just can't afford. If it wasn't for state insurance we woudn't go to the doc either. I know that the docs went to school for a long time to learn everything they need to know to help us and our pets but it would be real nice if they could lower their prices for those taht don't have insurance and are on tight budgets. My husband has a heart condition and he doesn't have insurance. He takes no meds and hasn't seen a doctor since his heart attack 4 years ago.
Sorry, got off the subject a bit there. I tend to ramble.
I do hope you find out whats wrong with your dog. Ours are our family members and we love them very much as i'm sure you do yours too.
If your dog is young and has any of the symptoms mine has you may want to have him checked for the kind of mange that is passed from mother to puppy or allergies. It is that time of year.