In fear of sounding cold, if your golden is a senior, it might be time to let him go. You mentioned the shots are no longer helping so he may be past the time to hope for remission. I lost my golden this past July, that call to the vet for her final appointment was the hardest call I've ever made. She was almost 14 y.o. I'm comforted knowing she's young and healthy again running and playing at Rainbow Bridge.