I have a serious question about my 8 month old red nose pit bull.?

Over the last month he has been itching and biting at his backside and tail. He gets regular baths with doggy oatmeal body wash for sensitive skin and i give him antibiotics for the itching and to prevent infections *vets prescription* and he is still doing it! He is covered in scabs and is now loosing his hair, and i don't know what to do for him. His last check up with the vet was 3 weeks ago and his veterinarian told me that's the best i can do for him because of his breed and he continued on saying that most not all pit bulls have sensitive skin. I am curious to know about any none medical treatments you would recommend and also if any of you have ever heard of pit bulls having sensitive skin? I am willing to try something new as long as its safe and there is research that back up the facts, thank you.