HI, I'm Dr Steve and I would like to help you with your dog's problem.
I see you have been to the vets about this problem and must not have seen any improvements. There can be several causes of facial scratching in dogs, one of them being ear infections. I will assume for now that his his ears are not infected. The other causes include allergies which can cause severe itching. This condition usually involves itching and scratching on other parts of the body like the front feet and sometimes the belly.
If there is no scratching anywhere but the face, allergies are not quite as likely. The other thing that I see occasionally that can cuase this problem is called Demodex. This is a mite that burrows into the hair follicles , especially on the head and face and causes irritation which makes a dog scratch.
This is diagnosed by scraping the skin with a surgical blade and looking at the material under a microscope to see the mite. Sometimes this condition is overlooked since it is not extremely common, but if the ears are ok and if your vet doesn't feel that allergies are the problem, then this would be worth checking out.
As for the breathing, there can be other causes for this as well. Heartworms can cause breathing difficulty, but also commonly causes a cough. Having a blood test will check for heartworms. The breathing can also be caused by a respiratory infection that your vet can determine by listening to the heart and lungs. Being uncomfortable and possibly in pain from the facial scratching can also cause stress which can cause an increased breathing rate.
Taking him back to the vet and asking for a heartworm test, discussing the possibility if a respiratory infection and having the face where the scratching is being done scraped for mites would be the next step to help see what exactly is going on with him. I see you are offline. I hope this has helped. I will be checking throughout the evening to see if you have any further questions. I wish you the best of luck and please keep me updated if you don't mind.
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