Welcome to pets.ca, StayAwake
.
I think if I were in your shoes, I'd call around and try to find another vet who has some better experience dealing with aggressive dogs
. You may want to try to sedate him at home with meds
before taking him to the vet's. He may also have a yeast infection in his ears which is why oral anti-biotics aren't working. As well, store bought ear cleansers made one of our dogs' ears much worse too because of the perfume in it.
Perhaps once his infection clears up, if possible, you may want to consult an experienced behaviorist about his aggresson issues. You'd be amazed all you can learn to help de-sensitize him to things he now fears.